Digitally controlled DC-DC converter with L5964 for ......• Input connector J1: is connected to the 12 Vdc power source and can accept an input voltage from 6 Vdc up to 26 Vdc. •

IntroductionTo meet the latest connectivity and fast charging requirements of portable devices, the very popular USB plug has evolved froma simple PC interface with limited power supply capabilities to the USB type-C standard capable of supporting multimediadevices, rapid battery recharging and supplying power to many types of portable devices with same standard connector.

The AEK-POW-L5964V1 power board is designed to operate as a power supply in USB Type-C systems for automotive andtransportation applications or to supply multimedia infotainment devices in car body applications.

The board has two independent converters that can deliver a selectable fixed output voltage or a set of variable ones, andpower level selection is performed via MCU control for an output current of up to 3 A on both channels. The converters areaccompanied by all the necessary protections against failures like overcurrent and overtemperature.

The board also includes monitoring circuits for input and output voltages and status LEDs. Appropriate filtering is implementedto minimize EMI.

The board is designed according to the AutoDevKit initiative, with a dedicated driver and basic demo software available inSPC5-Studio.

Figure 1. AEK-POW-L5964V1 digitally controlled DC-DC converter with L5964

Digitally controlled DC-DC converter with L5964 for automotive applications

AN5362

Application note

AN5362 - Rev 1 - July 2019For further information contact your local STMicroelectronics sales office.

www.st.com

https://www.st.com/en/product/aek-pow-l5964v1

1 Main characteristics and board description

The AEK-POW-L5964V1 evaluation board is designed for USB-PD 3.0 compliant, infotainment, in car dc-dcapplications. Its high efficiency and small size render the board suitable for applications involving limited availablespace.

AEK-POW-L5964V1 board features:

• Dual channel, independent, step-down regulators with integrated synchronous MOSFETs• Output current up to 3 A each channel• Channels can be paralleled to obtain a higher current supply• Input voltage range from 6 to 14 V• Digitally selectable fixed output voltages: 3.3 - 5 - 9 V• PWM programmable output voltages with 20 mV steps over a range of 3.3 - 11 V• Outputs protected against short-circuit and overcurrent• Input and output voltage monitors (UV or OV) and power good signals• Thermal protection thanks to the integrated thermal sensor• Additional 3.3 V output by internal linear regulator• Watchdog, reset, in/out synchronisation for available converters• Board size: 84.7 mm x 81.3 mm• Maximum component height: 10 mm• Automotive grade qualified ST components• Included in the AutoDevKit initiative• CE certified• RoHS and China RoHS compliant• WEEE compliant

The main DC-DC converter in the power board is the L5964 monolithic dual 3.5 A step-down switching regulatorwith LDO. It integrates control, power switches and monitoring circuits for both channels and additional featureslike Watch Dog, Wake up, Reset, etc.The power board is designed to work with an MCU board like the AEK-MCU-C4MLIT1. However, to build acomplete 2-port USB-PD system, you need to add an AEKD-USBTYPEC1 evaluation kit, which includes an MCUboard and a dual-port USB Type-C function board (AEK-USB-2TYPEC1). The kit also allows you to test the USBpower delivery protocol stack.

AN5362Main characteristics and board description

AN5362 - Rev 1 page 2/30

https://www.st.com/en/product/l5964

https://www.st.com/en/product/aek-mcu-c4mlit1

https://www.st.com/en/product/aekd-usbtypec1

https://www.st.com/en/product/aek-usb-2typec1

2 Connectors and interfaces

The power board AEK-POW-L5964V1 has the following interface connectors:• Input connector J1: is connected to the 12 Vdc power source and can accept an input voltage from 6 Vdc up

to 26 Vdc.• Output connector J3: both converter outputs are connected to J3, including GND signal; it is a standard 2x9-

pins female mounted on bottom side of the board, and is plugged to the AEK-USB-2TYPEC1 USB Type-Cexpansion board.

• Signal connectors J9, J10: are mounted on bottom side of the board, for connection to the USB Type-Cexpansion board; their purpose is to short certain signals once the power board is plugged onto the USBType-C expansion board to allow the delivery of the right voltage levels from the power board to the USBports.

• Signal connector J8: this 4x20-pin connector carries all signals necessary to control and monitor the powerboard from the MCU. This male/female connector can be used to stack additional boards on top. The 4x20pins on the female side are used to connect the power board to an SPC58 discovery board 4x37 maleconnector from lines 18 to 37.

Table 1. AEK-POW-L5964V1 signals to and from the MCU

Type Signal name MCUport

J8 pin#

Signal type /

IN/OUTTo/From Description

1 V0_3V3 PF11 A5 Flag - 3.3 V (GPIO) / IN From MCU O/p voltage setting - fixed

1 V1_3V3 PA0 B4 Flag - 3.3 V (GPIO) / IN From MCU O/p voltage setting - fixed

2 I_SENSE_0 PI6 B10 Analog / IN From Exp. board Buck2 o/p current sensing

2 I_SENSE_1 PG10 B15 Analog / IN From Exp. board Buck1 o/p current sensing

3 V1_PWM PE6 C1 3.3 V – var. duty / IN From MCU O/p voltage setting - fixed

3 V0_PWM PE5 D1 3.3 V – var. duty / IN From MCU O/p voltage setting - fixed

5 CC_REF_0 PE2 D17 3.3 V – var. duty / IN To CC E/A Buck2 Buck2 CC E/A reference

5 CC_REF_1 PF14 C6 3.3 V – var. duty / IN To CC E/A Buck1 Buck2 CC E/A reference

1 V0_20V PF2 D3 Flag - 3.3 V dc (GPIO) / IN From MCU O/p voltage setting - fixed

1 V0_15V PB11 D4 Flag - 3.3 V dc (GPIO) / IN From MCU O/p voltage setting - fixed

1 V0_9V PC2 D5 Flag - 3.3 V (GPIO) / IN From MCU O/p voltage setting - fixed

1 V1_20V PH1 D9 Flag - 3.3 V (GPIO) / IN From MCU O/p voltage setting - fixed

1 V1_15V PK1 C9 Flag - 3.3 V (GPIO) / IN From MCU O/p voltage setting - fixed

1 V1_9V PD4 D18 Flag - 3.3 V (GPIO) / IN From MCU O/p voltage setting - fixed

5 EN_0 PD12 D8 Flag - 3.3 V (GPIO) / IN From MCU Enable buck2

5 EN_1 PM2 D19 Flag - 3.3 V (GPIO) / IN From MCU Enable buck1

4 TJ_TEST_F PB7 D13 Analog (1÷2 V) / OUT To MCU ADC Chip temperature sensing

6 PGOOD_0 PI4 D11 Open Collector / OUT To MCU ADCVBUS_0 out of tolerance

è LOW

6 PGOOD_1 PI7 C10 Open Collector / OUT To MCU ADCVBUS_0 out of tolerance

è LOW

4 VBUS_0_ADC PG9 D12 Analog - 0.5÷1.7 V / OUT To MCU ADC VBUS_0 o/p voltage sensing

4 VBUS_1_ADC PG6 C12 Analog - 0.5÷1.7 V / OUT To MCU ADC VBUS_1 o/p voltage sensing

4 VIN_ADC PB6 C13 Analog - 0.9÷2.7 V / OUT To MCU ADC I/p voltage sensing

AN5362Connectors and interfaces

AN5362 - Rev 1 page 3/30



Type Signal name MCUport

J8 pin#

Signal type /

IN/OUTTo/From Description

7 5V - B20 dc power supply To J3-17 (VCONN) 5 V from SPC58 discoveryboard

7 VEXT - D20 dc power supply To J3-18 12 V SPC58 discovery board I/Pvoltage - unused

7 VEXT_P - A20 dc power supply From MCU board 12 V I/P voltage – jumper -unused

7 VEXT_P - B20 dc power supply From MCU board 12 V I/P voltage - jumper -unused

7 3V3_CH - C20 dc power supply From MCU board 3.3 V from SPC58 discoveryboard - unused

5 GND - C19 From MCU board GND

Table 2. Pin type legend

Pin type Purpose

1 Signals setting for fixed o/p voltage

2 Signals for programmable cc loop

3 Signals for programmable o/p voltage

4 Analog signals for MCU ADCs

5 Signals mandatory for board operation

6 Digital flag signals

7 dc supply/GND on 4x 19-pin connector

• Test connectors J6, J7: two connectors, one for each buck converter, are provided for test purposes. Thesignals available are LDO o/p voltage, EN, PGOOD, o/p voltage selection flags. By shorting certain pins likeLDO and EN, it is possible to obtain converter operation without the MCU connected. In the same way, it isalso possible to easily select the o/p voltage.

• Synchronization connector J5: L5964 has two pins to synchronize the buck converters in case of operationwith other converters working as slaves. Additionally, it delivers a synchronization signal that can be used tosynchronize other converters working as masters. Because these features are not used on the power board,this connector is not mounted.

• Signal IN/OUT connector J4: Other functions embedded in the L5964 to control the MCU are unused, butavailable on connector J4. This connector is not mounted on the board.

AN5362Connectors and interfaces

AN5362 - Rev 1 page 4/30

3 Functional blocks and circuit descriptions

The block descriptions and concepts associated with converter Buck2 supplying VBUS_0 are exactly applicableto the mirrored circuits for Buck1 supplying VBUS_1, only the component references change.

3.1 Power stages and buck converters

The two converters delivering the output voltages are based on a typical buck topology with synchronousrectification to increase the efficiency. Both switches are N-channel MOSFETs, integrated in the L5964. Theswitching frequency selected is 250 kHz for both converters in order to obtain a good compromise betweencomponent sizes and switching losses. The L5964 manages operation of both converters 180° out-of-phase tominimize the input ripple. The operating frequency of both converters can be selected by resistors R34 and R35.Both stages have an individual Pi-filter input to minimize the differential mode noise (C24, L2, C25, C26). Theoutput power stage only needs an inductor and an electrolytic capacitor (L4 and C32) for energy storage at anyswitching cycle. An additional small ceramic capacitor is added in parallel with the electrolytic capacitor todecrease noise spikes. To protect from negative spikes due to the parasitic inductances, a small Schottky diode isadded in parallel (D4) on each phase pin.As the conducted noise generated by converters can affect other external circuits, an additional Pi-filter is placed(C1, L1, C2) close to the input connector to filter both differential and common mode noise.

3.2 Output voltage regulation loops

The L5964 embeds two regulation circuits to independently control the output voltage of both converters in atypical current mode with slope compensation. All the blocks needed for the control portion are integrated; onlythe compensation network (R53, C21, C23) and the feedback network have to be connected externally. Thevoltage loop error amplifier is a trans-conductance type and the compensation network is a typical type-2 networkconnected to ground.The feedback network is more complex than a usual simple voltage divider because the functions required by theUSB-PD specification are implemented through this block. As soon as input voltage is provided, the power boardsupplies a fixed default voltage (5 V); a different fixed output voltage is selectable via the MCU. The power boardalso supplies a variable voltage from 3.3 V to 11 V to support the Programmable Power Supply (PPS) Voltagemode according to the USB Power Delivery standard version 3.0. The fixed voltage and PPS operating modescan be independently applied on each of the two L5964 converters, so a converter can regulate a fixed voltage onone channel while the other channel is regulated according to the PPS at any voltage in the available range.

Figure 2. Fixed output voltage feedback loopschematic-1

FB2

PHASE2VBUS_0

V0_9V

V0_PWM

V0_20V

V0_15V

V0_3V3

R63

C51R47

C33

Q1-1

6

2

1

R45

R121

R58

TP11R122

Q1-23

5

4

C45

R75

R80

C48

C32

C46

Q2-16

2

1

R120

Q2-23

5

4

R73

R44

L4

R66

D15

R37

R82

R78

R64

C41

R46

R77

C39

2 2

Figure 3. Variable output voltage feedback loop forPPS-Voltage mode schematic-2

FB2

PHASE2VBUS_0

V0_9V

V0_PWM

V0_20V

V0_15V

V0_3V3

R63

C51R47

C33

Q1-1

6

2

1

R45

R121

R58

TP11R122

Q1-23

5

4

C45

R75

R80

C48

C32

C46

Q2-16

2

1

R120

Q2-23

5

4

R73

R44

L4

R66

D15

R37

R82

R78

R64

C41

R46

R77

C39

AN5362Functional blocks and circuits description

AN5362 - Rev 1 page 5/30



The feedback circuit schematic above can be split into the functional blocks described below.

Default output voltage

If no voltage selector signal is applied to the power board, the default output voltage is 5 V according to the USB-PD specification. The components used to set the default voltage are included in the area inside the dashed line:R37, R44, R58 implement a typical fixed voltage divider. The inverting input of the error amplifier is connected tothe common point of the FB2 feedback voltage divider.

Fixed output voltages

Apart from the default 5 V, the USB-PD specification recommends the additional 9 V, 15 V, 20 V fixed outputvoltages. As the converter topology is buck, the power board can only deliver output voltages below the input; thatis, 5 V and 9 V. However, the circuitry required to support operation at 15 V and 20 V is in place, and these highervoltages may be supported by future versions of the L5964. If the higher voltages are not needed, this section canbe removed from your design.The power board provides different output voltages when one or more resistors are placed in parallel to changethe voltage set point. The MCU provides a TTL signal activating one or more of the three small signal MOSFETsthat tie R45, R46, R47 to GND. These resistors are visible inside the dotted line in Figure 2. Resistor R37 is thetop resistor of the feedback divider and is shared if other bottom resistors are tied to GND to obtain highervoltages.An additional 3.3V is available for USB-PD PPS operation and can also be used as a supply voltage when theboard is used as generic power supply. Both converters can deliver all mentioned voltages up to maximumcurrent of 3 A each.For both channels, the fixed output voltage can be set independently by providing signals according to the tablebelow. If no output voltage overrides are set by the MCU, the board delivers the default 5 V voltage. Eachconverter has to be enabled by pin EN_x = H and signal CC_VREF_x has to be set at 3.3 Vdc, even if the currentlimiting function by the output current regulation loop is unused.

Table 3. Fixed output voltage selection table

VBUS_x Vx_3V3 Vx_9V Vx_15V Vx_20V Vx_PWM EN_x CC_VREF_x

5 V L L L L OFF H H

9 V L H L L OFF H H

15 V L H H L OFF H H

20 V L H H H OFF H H

Variable output voltage for PPS-Voltage mode

The AEK-POW-L5964V1 power board also allows programming the output voltage in a range from 3.3 V to 11 V,as required by the USB Power Delivery 3.0 specification for the Programmable Power Supply (PPS) operation.In the PPS implementation by ST, the MCU delivers two dedicated signals to each converter: one is a dc TTLfixed signal (Vx_3V3, e.g. an MCU GPIO), and the other is a PWM TTL signal where its duty cycle is proportionalto the required output voltage (Vx_PWM). These signals are provided the on 4x20 pin connector J8.The dc TTL fixed signal Vx_3V3 is required to decrease the 5 V default output voltage to 3.3 V; this functionality isimplemented through a circuit injecting current into the FB1 node (see solid line rectangle section in Figure 3).When any other higher output voltage is needed, the PWM signal Vx_PWM with a suitable duty is applied. Thissignal provides an on-off operation on the small signal MOSFET Q1 which, by means of R63, will partiallydischarge C39. As C39 and R63 have a larger time constant compared to the PWM signal, the result is anintegration of the PWM signal coming from the MCU. R44 then removes some current from the feedback node,thus causing an increase in the output voltage proportional to the duty of the PWM signal coming from the MCU.As this is an analog circuit, the minimum variation for a single step depends on the granularity of the PWM signaldriving the small signal MOSFET Q1. Once the converter is in PPS-Voltage mode, the signals setting fixed outputvoltages have to be set Low.The relationship between the PWM signal from the MCU and the output voltage for VBUS_0 is:

AN5362Output voltage regulation loops

AN5362 - Rev 1 page 6/30


VBUS_0 = R37 × VFB0R44 + R58 × R63δ × R58 + R63 − VGPIO − VFB0− VFR121 + R122 + VFB0 (1)

Where:• VBUS_0 = output voltage• VFB0 = L5964 feedback voltage of voltage loop• VGPIO = peak voltage of the PWM signal, V0_PWM (typ. 3,3 V, from MCU)• VF = Schottky diode D15 forward voltage drop• δ = duty cycle of V0_PWM signal (from MCU)• R37, R44, R58, R63 = PWM circuit resistors (on power board)• R121, R122 = setting resistors of the output voltage at 3.3 V (on power board)

As shown by the formula, the output voltage changes only due to the duty cycle of the control signal coming fromMCU, while the other elements can be considered constant. Given that the signal frequency is not involved in thecalculation, the same frequency can be selected in a wide range of possible values.Alternatively, the MCU can work by delivering a fixed on-time signal and changing the frequency to obtain the dutycycle needed to supply the load with the output voltage required.In Figure 4, the above equation is represented as a diagram showing the output voltage VBUS_x versus the dutyof signal from MCU, Vx_PWM. Figure 5 instead shows the duty necessary to obtain a desired output voltage.

Figure 4. Vout vs. Vx_PWM duty

0 0.025 0.05 0.075 0.1 0.125 0.15 0.175 0.2 0.225 0.25 0.275 0.33

3.54

4.55

5.56

6.57

7.58

8.59

9.510

10.511

11.512

δVO

UT(

)

δ

Figure 5. Vx_PWM duty vs. Vout

3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 11.5 120

0.025

0.05

0.075

0.1

0.125

0.15

0.175

0.2

0.225

0.25

0.275

0.3

δV O

UT

()

V OUT

The signals required for variable output voltage operation are given in Table 4. If the Vx_PWM signal from MCU isnot applied, or it has duty = 0, the board delivers the default 3.3 V. The desired output voltage can be set applyingthe Vx_3V3 signal to each channel and the relevant Vx_PWM signal with suitable Ton-time and frequency. As forfixed output voltage operation, each converter has to be enabled by EN_x = H and signal CC_VREF_x has to beset at 3.3 Vdc.

Table 4. Variable output voltage selection table

VBUS_x Vx_3V3 Vx_9V Vx_15V Vx_20V Vx_PWM EN_x CC_VREF_x

5 V H L L L ON H H

9 V H L L L ON H H

15 V H L L L ON H H

20 V H L L L ON H H

AN5362Output voltage regulation loops

AN5362 - Rev 1 page 7/30

3.3 Output current regulation loops

The AEK-POW-L5964V1 embeds the circuitry on both converters to support constant current operation. In thisoperating mode, the converter changes from maintaining constant output voltage like a voltage generator tolimiting the output current like a current source. This functionality is not only required to limit the output power incase of failures, but also for battery charging or when connecting a load that behaves as a voltage source, as inthe USB-PD 3.0 load direct charging operation.The simplified schematic of the constant output current feedback loop for Buck2 is shown in Figure 6. The circuitis based on an additional error amplifier in which the output pin is OR-ed with the voltage loop error amplifieroutput pin COMP. The voltage and current loops always complement each other, regulating the output voltage orcurrent according the load resistance value.The error amplifier inverting input is connected to the current sensing circuit. The current sensing circuitry is notpresent on the AEK-POW-L5694V1 power board as it is implemented on the AEK-USB-2TYPEC1 dual-port USBType-C expansion board, and the signals can be routed to the power board via the 4x20 pin connector J8(I_SENSE_x).

Figure 6. Simplified schematic for constant output current feedback loop (Buck2, VBUS_0)

VVout

Rload

AIload

U4

R97

Rsense

100

R99

C57

R100

R98

COMP

FROM uP

POWER BOARD

I_SENSE_1

CC_VREF_1

Output current is set by the MCU via a CC_VREF_x signal for each converter, which are TTL PWM signals withvariable duty proportional to the output current set point. Both are connected on the 4x20 pin connector J8. Thiscircuitry meets the PPS current requirement of the USB-PD specification 3.0, which requires control over themaximum output current from 0 A to 3 A with 50 mA steps and allows the direct “cold” charging control of thebatteries.The constant current circuit implements a feedback network sensing the output load current. An equivalentsensing resistor producing a voltage on the inverting pin of U4 can be calculated as:Re qsense = Rs × Ksns × R100R100 + R99 = 0.909Ω (2)

Where:• Rs = output current sensing resistor (on USB-PD expansion board)• Ksns = gain of sense amplifier (on USB-PD expansion board)• R100 = divider resistor (on power board)

AN5362Output current regulation loops

AN5362 - Rev 1 page 8/30



• R99 = divider resistor (on power board)

Presuming the perfect integration of the waveform by capacitor C57, the reference voltage Vref_x applied at non-inverting pin of U4 is: Vref_x = CC_VREF_x × δ × R97R97 + R98 (3)

Where:• CC_VREF_x = Peak voltage of the PWM signal (typ. 3,3 V, from MCU)• δ = Duty cycle of the PWM signal (from MCU)• R97 = divider resistor (on power board)• R98 = divider resistor (on power board)

Combining Eq. (2) and Eq. (3), and considering the constant quantities in both, we can simplify these into thefollowing equation: Ioutx = ∂0.286 (4)

The above equations are linear and thus perfect linear proportionality is achieved among the duty cycle variationsof the signal CC_VREF_x coming from the MCU and the output current of the same buck converter channel.

3.4 Overcurrent protection

The L5964 integrates protection functions such as embedded pulse-by-pulse overcurrent protection to limit thecurrent peak converters in an overcurrent or short-circuit event. The trigger threshold can be set at 50% or 100%through the OCPSETx pins.

3.5 Power good signals

Converters are provided with undervoltage (UV) and overvoltage (OV) protections, fully integrated into the L5964.The IC internal circuitry monitors the FBx pin of both converters and pulls down the relevant pin if the voltagedeviates from nominal value. On the power board, the power good signals are combined and connected to theMCU via the 4x20 pin connector J8 (PGOOD_x); PGOODx signals are active low.

Note: The PGOOD signal goes low during constant current control because the load resistance causes the outputvoltage to drop below the nominal value, and the voltage loop is not regulated.To simplify the interface with MCU, the PGOOD_x signals can be delayed by a capacitor connected to pins #64and #2 if necessary.

3.6 Voltage monitoring

To control the converters via the MCU, both the input voltage and output voltages are supplied via their respectivevoltage divider, scaling to a level compatible with microcontroller ADCs. A small capacitor for noise filtering isprovided too. These signals (VIN_ADC and VBUS_x_ADC) are connected to the 4x20 pin connector J8.

3.7 Temperature monitor and overtemperature protection

The L5964 has a dedicated pin with a voltage proportional to the chip temperature (pin TJTEST). The signal fromthis pin is filtered and sent to the MCU via the 4x20 pin connector J8. Additionally, if the L5964 temperatureincreases excessively, an internal protection stops the converter duty until the temperature has returned toacceptable levels.

3.8 LEDs

The board has LEDs to highlight certain signal activation.

AN5362Overcurrent protection

AN5362 - Rev 1 page 9/30

Table 5. Signal LEDs

Signal LED Color Status

VOUTLDO D2 Red ON

EN_0; EN_1 D6; D7 Yellow ON

Vx_9V U2; U3 Blue ON

Vx_15V U2; U3 Green ON

Vx_20V U2; U3 Red ON

3.9 LDO and additional functions

The L5964 integrates an LDO used to supply 3.3 V to some auxiliary circuits like the constant current erroramplifiers or the LEDs, and is also connected to one of the test connector pins for evaluation purposes. The LDOoutput voltage can be programmed by a divider connected to a dedicated pin, the maximum limiting current is380 mA in normal mode, and it may also be used to supply the system MCU. LDO power dissipation should beconsidered when calculating the total losses of the L5964 to provide enough margin for long term operation. Apower good pin is provided and is available on J4.Additional functional blocks integrated in the L5964 are Watch Dog input, WakeL, High-Side Driver Enable, Resetand Ignition buffer. These functions are currently unused on the power board, but are available on connector J4for additional custom functionality.

Figure 7. AEK-POW-L5964V1 schematic diagram

VBUS_0_ADC

RGB

PI9

5

R25N.M.

6

3V3

B16

PGOV234

C206N8

A14

2

C14N.M.

R508K66

R9127K

R9722K

C44N.M.

PGOOD_0

6WAKEL

7

5

5V

R29N.M.

C3

A6

D16

3

NC26

R9N.M.

WDI

PF13

R6110R

4

R6522K

MODE1

1

EN_1

PG

ND

130

3

Q2-12N7002DW

15

VOUTLDO

C4

3

N.C

.18

J4N.M.

C51N0

Q2-22N7002DW

TLM

S100

0-G

S08

1

WD

I51

J2

N.M.

V_EXT_P

Q1-22N7002DW

VCONN

SUB8

R67100R

R8560K

V0_9V

Q1-12N7002DW

B19

EN

LPM

57

PF2 V0_20V

J5N.M.

VOUTLDO

PM2 EN_1

C271uF

PGOOD_1

1

RED ON ==> 20 V OUTPUTGREEN ON ==> 15 V OUTPUTBLUE ON ==> 9V OUTPUT

1

TLM

Y100

0-G

S08

B3

C12

GND

R30N.M.

GND SIGNAL DC/DC

HS1HEAT-SINK

GNDEN_1

SYNC IN/OUT

R114560K

PGOOD_1

EN_1

PH1 V1_20V

R40R0

3

PA3

R125100K

C4100N

D10BAT46

A19

R14N.M.

R74100K

6

R86330R

3

D6

D10

3

14

R841K2

NC15

2

V0_15V

12

5

NC14

13

V0_15V

J8BFEMALE/MALE 20x4 ROWS

TP3

C501N5

R4710K

2

R12433K

B13PE0

5

B12

3V3

OCPSET133

2

A18

C59100N

1

C7100N

R111K2

PG14

5

V_EXT

R11927K

PF0

J7STRIP 8x1

V0_PWM

6

R83100K

C3810N

A9

1

V0_9V

A5

C641N0

C56100N

C7

R694K7

NC34

C611N0

R931K2

ENBUCK114

3V3

R468K66

R23N.M.

FB24

V1_9V

R5811K

1

D14

C512N2

SY

NC

OU

T61

EN_1 = 1 ==> ENABLE BUCK1 / VBUS_1 ON

TJTEST42

2

R10710K

PGTHLDO46

4

+

-

+Vcc

GND

R54N.M.

A13

2

N.C

.22

3

4

C662N2

5

ENBUCK215

C11100uF

J1PWR-IN CONNECTOR

C151N0

C601N0

R4056K

D6

1

R5911K

2

SY

NC

IN62

23

8

D5

C16

NC

C291uF

C15

X8s

PB6VIN_ADC PB7

VBUS_1

78

PF14CC_VREF_1

R72220R

V0_20V

PD2 PE7

2

R106100R

PGOOD_0

B17

B5

B18

3

C6100N

1

EN_0

4

C11

BC84

6BD

W1T

1G PD13

Q6A

D8BAT46

FB144

PE8

R11022K

TP11

6

1

VOUTLDO

C4110N

V1_20V

R7110K

6

R5710K

NC27

PF12

R4512K4

PG

ND

129

D3N.M.

B9

PGOOD_1

5

C58100N

6

PG9 VBUS_0_ADC

R6100K

R12336K

1

C3100N

PA0 V1_3V3

PG

ND

219

VOUTLDO

R10110K

N.C

.24

A8

C55100N

R11827K

N.C

.50

B11

TP9

D5STPS2H100ZFY

BS211

FDIVISION7

RESET

R8927K

R8810K

CC_VREF_1

B20

PD4 V1_9V

INPUT SIGNAL CONNECTOR - BOTTOM SIDETO USB-PD EXPANSION BOARD/CHORUS BOARD

R102330R

V0_9VV0_15VV0_20VV0_PWM

1

3

R53N.M.

VINBUCK139

C10

B15

TAB

49

D18BAT46

C2856uF

R1260R0

+VIN

GND

R8022K

A3

PD12 EN_0

3V3

R120R0

PD5

V1_15V

L533 uH

4

L34.7 uH

PC2 V0_9V

Q3-12N7002DW

V0_3V3

PI2

R22560K

R20N.M.

D4STPS2H100ZFY

D11

R441K2

NC6

16

L24.7 uH

R78100K

GNDEN_0

PA11

PG4

9

V0_9V

PA10

A4

11

C3147N

3

IGN_BUF

4

B14

OC

PS

ET2

32

NC24

A17

1

1

J10STRIP 2x1

Q7B

EN_1

4

PC14

4

C19N.M.

V0_20V

R10110K

3

BC84

6BD

W1T

1G

TP7

R704K7

V0_15V

1

TJTEST

R20R0

2

NC36

R17N.M.

R1040R0

RGB

C23330PF

U3LED CA RGB SMD

U5TSX711ILT

UV

128

2

COMP23

U1L5964L-VYY

C3047N

R28100K

C63100N

B8

WD

I

B7

VOUTLDO

RE

SE

T21

D15

PGOOD_0

INPUT VOLTAGE

VO

UTL

DO

53

(24 V max)R16100K

RED ON ==> 20 V OUTPUTGREEN ON ==> 15 V OUTPUTBLUE ON ==> 9V OUTPUT

EN_0 = 1 ==> ENABLE BUCK2 / VBUS_0 ON

1V-1.65V

D18

C121N0

A12

BC84

6BD

W1T

1G

IGN

_BU

F23

R5610R

5

VBUS_0

PGTH116

C241uF

C4810N

VINBUCK210

PE15

18

+

-

+Vcc

GND

Q8B

1

R68100K

R260R0

IGN_BUFRESET

4

2

EN

LDO

59

SIGNAL IN/OUT

PHASE136

C14

R510R

Zout ~100kOhm

R3N.M.

C3947N

4

VBUS_0

PD8

PI3

C57100N

3

C22330PF

PM14

2C9100N

PE6V1_PWM

3V3_CHPG15

R33220K

WA

KE

L58

TP4

B4

PG12

1

V0_PWM

N.C

.63

PG5

R621K2

D16BAT46

R6422K

FB1

4

SYNCOUT

COMP145

VBUS_1

D3

PGD2/PUPDL2

WAK

EL

D19

I_SENSE_1

C1

NC28

7

R9027K

PI8

Q4-12N7002DW

PF11V0_3V3

C17100N

V1_15V

GND

2

PB11 V0_15V

N.C

.31

1

R31220K

2

J3POWER CONNECTOR 9x2

2

2

VIN_ADC

5

4

4

HSD

_EN

2

C20

C181N0

D2

C4047N

A7

R851K8

R5110K

Q6BBC846BDW1T1G

D13BAT46

B10

PHASE212

R12133K

SWGND26

PG3

R12236K

D4

PE2 CC_VREF_0

R1090R0

VOUTLDO

1

D20

SYNC IN

6

X8s

X8s

X8s

X8s

X8s

X8s

TLM

Y100

0-G

S08

8

VINBUCK140

5

C9

R240R0

SUB48

+3V3

BS138

C11uF

R11627K

GND PWR DC/DC1

GND PWR DC/DC2

3V3 CONNECTOR

UV

226

TP12

A1

I_SENSE_0

R941K8

C16N.M.

PG10 I_SENSE_1

SYNCIN

C33100N

L433 uH

PA3

R6010R

BC84

6BD

W1T

1G

TP2

D12

L1ACM12V

PGLDO

PI7PGOOD_1

D13

WAKEL

C18

HSD_EN

X8s

NC5

J6STRIP 8x1

C2

8

PG11

C216N8

VOUTLDO

C35470uF

PGLDO43

C13N.M.

R19N.M.

3V3_CH

Q8A

R41N.M.

PI5

PGOV135

2

NC23

R120100K

R921K2

2

NC7

1

A15

C4610N

VCONN

D11BAT46

A16

R77100K

3

EN_0

C4910N

TP1

2

HSD_EN

V1_20V

A2

D17

5

V1_9V

1

D12BAT46

NC37

PF1

R150R0

7

2

N.C

.27

FB1

B6

C251uF

C6

17

2

C5

N.C

.25

1

VB

AT55

R1031K0

2

C4710N

1

TP6

C21uF

2

FBLD

O52

R991K0

R4912K4

C4310N

C45N.M.

V_EXT_P

3

C2656uF

BC84

6BD

W1T

1G

1

Q4-22N7002DW

R11110K

PG

TH2

17

R8122K

VINBUCK29

PE5 V0_PWM

V0_20V

VOUTLDO

V_EXT

*Rev. 2.2

2

1

D7

HS

D_E

N56

C13

SYNC OUTGND

5

V1_9VV1_15VV1_20VV1_PWM

B1

C651N0

V1_15V

R11727K

RESET

R5510R

PI4 PGOOD_0

R7522K

C62100N

PG2

V1_9V

4

C810uF

R3468K

PI6 I_SENSE_0

PC7

V1_PWM

R2147K

A20

R18N.M.

B2

2

Q3-22N7002DW

PG

D1/

RS

TDL

64

D9D17BAT46

D15BAT46

TP8

NC16

1

D1

R10010K

5

R32N.M.

PG1

1

PE3

R42N.M.

PGLDO

1

Q7ABC846BDW1T1G

6

V1_20V

V1_3V3

6

V1_PWM

3

VBUS_1_ADC

NC35

C4210N

C10N.M.

CC_VREF_0

C19

4

J8AFEMALE/MALE 20x4 ROWS

R82100K

PG

ND

220

R7622K

J9STRIP 2x1

A10

C8

NC25

R98560K

A11

PHASE213

R8727K

SWGND15

PG

DLL

DO

60

1

IGN_BUF

Q5B

PGLDO

C34100N

WDI

D8

PL8

R1121K0

VOUTLDO

1

5

6

D7

TP5

R1820K

BUCK1 TEST CONNECTOR

BUCK2 TEST CONNECTOR

PLUG-IN CONNECTORS - BOTTOM SIDETO USB-PD EXPANSION BOARD

PD1

TP10

Q5ABC846BDW1T1G

FREQSET41

2

AGND47

R7100K

R631K2

ANALOG GND / GND PLANE

4

RED

D14BAT46

R1131K0

EN_0

VOUTLDO

D2

R66100K

C32470uF

U4TSX711ILT

R3756K

2

6

U2LED CA RGB SMD

PHASE137

R95100R

2

TJTEST

R43N.M.

R481K2

R79100K

R1151K2

PK1V1_15V

C17

GND

R73220R

R350R0

R13N.M.

10

VIN

LDO

54

R52100R

PG6VBUS_1_ADC

AN5362LDO and additional functions

AN5362 - Rev 1 page 10/30


4 Connecting the power board

The AEK-POW-L5964V1 power board can be connected to an MCU board.When connecting the boards, ensure that the pins in row #20 of the power board connector J8 coincide with pinsin row #37 of the X9 (4x37-pins) connector of the MCU. The additional connections and signals required by thepower board and MCU are listed in Table 6.

Figure 8. Power board plugged on MCU board

Table 6. Connections for operation with MCU

Connector Board/position Type Voltage Remarks

J1 Power board / top layer Screw connector 12 V typ @6 A Input power connector

J8 Power board / bottom layer4 x 20-pins

2.54mm pitch

Signal connector, plugged to X9 of the MCU.J8 row 20 has to match X9 row 37 of theMCU


2.54mm pitchOutput voltage connector

X5 AEK-MCU-C4MLIT1 / toplayer Jack 12 V typ @1 A MCU power connector

P3 AEK-MCU-C4MLIT1 / toplayer USB-Mini USB cable for communication with MCU

4.1 Operation with USB Type-C function board (AEK-USB-2TYPEC1)

The AEK-POW-L5964V1 power board is designed to provide the required voltages to a complete 2-port USB-PD2.0 unit, which can be implemented with the AEKD-USBTYPEC11 kit with an MCU and dual-port USB Type-Cfunction board (AEK-USB-2TYPEC1).In Figure 9, the power board is oriented above the USB Type-C function board to facilitate air flow for cooling ofthe power circuits. Check that all connector pins match correctly with bottom ones when plugging the boards. TheUSB type-C functional board is plugged onto the MCU board by aligning pins #39 and #40 of connectors J101and J102 with pins #37 row A to D of the X9 (4x37 pins) connector of the MCU. The MCU provides the signalsrequired to operate the entire system, and the software provided allows evaluation of board functionality and theUSB-PD 2.0 protocol.

AN5362Connecting the power board

AN5362 - Rev 1 page 11/30


https://www.st.com/en/product/aekd-usbtypec1


Figure 9. Power board with MCU board and 2-port USB-PD interface board

For power board with MCU testing, the following connections and signals are required:

Table 7. Connections for operation with complete USB PD kit

Connector Board/position Type Voltage Remarks

J1 Power board / top layer Screw connector 12V typ. @ 6A Input power connector


2.54mm pitch- Output voltage connector

X5 AEK-MCU-C4MLIT1 /top layer Jack 12V typ @ 1A MCU power connector

P3 AEK-MCU-C4MLIT1 /top layer USB-mini - USB cable for communication with MCU

4.2 Standalone operation

The AEK-POW-L5964V1 board can also operate with limited functionality in standalone mode without MCUcontrol. While some of the MCU signals must be compensated with external signals, standalone operation allowsthe overall design to be simplified as the circuitry associated with MCU control can be omitted. This solution issuitable for supplying power to infotainment, multimedia, and other car body applications, and for testing theboard in general.The signals to be applied can be found in Table 1 or in Table 3. The basic signals for converter operationexcluding the input supply voltage are:• EN_x set high• voltage selector signals set high according to the required output voltage• CC_VREF_x set to 3.3 Vdc (the 3.3 V from the LDO can be used to provide the required voltage to the

CC_VREF_x pin)

AN5362Standalone operation

AN5362 - Rev 1 page 12/30


5 Fixed output voltage and efficiency at 12 Vdc input voltage

This section provides some test results for the board in standalone mode. The main parameters were checkedand the efficiency was calculated at different loads. The input voltage was a nominal 12 Vdc, and the loads weresimilar on both channels through an active load working in constant current mode. Input and output voltages weremeasured at the board connectors. All measurements were recorded after after 30 minutes warm-up time.

Table 8. Voltage measurements and efficiency calculation• VLDO = 3.308 V

Vin

(V)

Iin

(mA)

Pin

(W)

Vbus0

(V)

Ibus0

(A)

Vbus1

(V)

Ibus1

(A)

Pout0

(W)

Pout1

(W)Efficiency

12.470 0.459 5.72 5.055 0.508 5.079 0.500 2.568 2.541 89.26%

12.390 0.798 9.89 9.123 0.508 9.177 0.500 4.634 4.590 93.30%

12.370 0.894 11.06 5.048 1.007 5.072 1.000 5.081 5.072 91.81%

12.230 1.584 19.37 9.119 1.007 9.173 1.000 9.183 9.173 94.75%

12.140 1.833 22.25 5.043 2.008 5.067 2.000 10.126 10.133 91.04%

11.810 3.299 38.96 9.114 2.009 9.169 2.000 18.310 18.337 94.06%

12.200 2.839 34.64 5.044 3.012 5.068 3.002 15.193 15.214 87.79%

12.000 4.979 59.75 9.167 3.002 9.109 3.012 27.523 27.436 91.99%

Table 8 and Figure 10 show a very high effeciency above 91 % when the converters are both working at 9 Voutput voltage for any output current value.

Figure 10. Overall efficiency vs. output current

Figure 11 shows the output voltage and phase waveforms of the two buck converters. Both converters aresynchronized and working at 283.6 kHz. The top waveforms relate to the Buck1 converter delivering 9 V onVBUS_1, while the bottom one is supplying 5 V. The Measurements on the right side show the difference in dutycycle together with output voltages.

AN5362Fixed output voltage and efficiency @ 12 Vdc input voltage

AN5362 - Rev 1 page 13/30

Figure 11. Buck waveforms – Vin = 12.5V, Vbus_1 = 9 V @ 3 A, Vbus_0 = 5 V @ 3 A

• Legend: CH1:VBUS_1; CH3: PHASE1 (TP7); CH2: VBUS_0; CH4: PHASE2 (TP6)

Figure 12 shows a maximum ripple of 25 mV by the channel working at maximum output power. Spikes and highfrequency noise visible in the picture are not significant because it is radiated noise picked-up by the probeground wire.

Figure 12. Output voltage ripple - Vin = 12.5V, Vbus_1 = 9 V @ 3 A, Vbus_0 = 5 V @ 3 A

• Legend: CH1: VBUS_1; CH2: VBUS_0

A significant contribution to differential mode noise reduction is given by the L5964 interleaving operation. The twoconverters are 180° out of phase, which minimizes input current ripple. This helps reduce the differential modenoise and optimize the buck input capacitor sizes.Additionally, lower ripple current means significantly lower stress for input capacitors, which increases theirlifetime.The interleaving operation can easily be observed when both converters are working at the same duty cycle.Figure 13 demonstrates the out-of-phase operation mentioned above, the phase shift is measured on right side ofthe image.


AN5362 - Rev 1 page 14/30

Figure 13. Buck waveforms – Vin = 12.5V, Vbus_1 = 9 V @ 3 A, Vbus_0 = 9 V @ 3 A

• Legend: CH1: VBUS_1; CH3: PHASE1 (TP7); CH2: VBUS_0; CH4: PHASE2 (TP6)


AN5362 - Rev 1 page 15/30

6 Operation with MCU

The AEK-POW-L5964V1 power board is designed to operate with an MCU control board. When connecting theboards, ensure that the pins in row #20 of the power board connector J8 coincide with pins in row #37 of the X9(4x37-pins) connector of the MCU.

Figure 14. Power board plugged on MCU board

6.1 Variable output voltage (PPS-V mode)

Figure 15. VBUS_1 output voltage vs. V1_PWM duty cycle

The above figure shows the characteristics of the power board controlled by the MCU and the simulation of thevoltage steps of the USB-PD PPS-V function from 3.3 V to 10.2 V with incremental steps of 20 mV.The test results relate to an open loop operation, where the board output voltage is set by the PWM signal andonly measured by employing an MCU ADC without any sort of regulation or adjustment of the output voltage bythe MCU. This gives an idea of the precision of the power and control circuits of the power board, which showsvery high linearity and monotonic behavior of the output voltage versus the duty cycle.

AN5362Operation with MCU

AN5362 - Rev 1 page 16/30

Thanks to functionality like the PPS-V mode operation, the board can be used to supply very precise voltages tocritical loads or devices requiring very fine supply voltage adjustment, or to implement precise digital cable dropcompensation.Figure 16 shows some waveforms for PPS-V operation. We can observe that the Buck1 converter is delivering5.85 V to the output load and the V1_PWM signal frequency is 142.1 kHz with duty cycle 7.806 %. The othersignals on the oscilloscope image both have logic levels high: EN_1 enables Buck1 converter operation, whilePGOOD_1 high signals that the output voltage regulation loop is working properly and the voltage level isappropriate.Figure 17 shows an increased measured voltage of 10.68 V because the V1_PWM signal now has a frequency of294.1 kHz with duty cycle 25.72 %. The channel 2 signal is the voltage on cathode converter measured at about3.3 V because the signal CC_VREF_1 is higher than the current feedback signal I_SENSE_1. Therefore, thecurrent loop error amplifier U5 is not regulating the output current while the output voltage is being regulated bythe voltage loop through the L5964 error amplifier.The signal on channel 3 is the PHASE_1 voltage measured in TP1. It represents a typical waveform for a buckconverter on switching elements before the output filter.

Figure 16. Waveform details during PPS-V operation – Vin = 12 V, Iout = 1 A

• Legend: CH1: VBUS_1; CH2: EN_1; CH3: PGOOD_1; CH4: V1_PWM

Figure 17. Waveform details during PPS-V operation-2 – Vin = 12 V, Iout = 1 A

• Legend: CH1: VBUS_1; CH2: D10-K VOLTAGE; CH3: VPHASE_1; CH4: V1_PWM

AN5362Variable output voltage (PPS-V mode)

AN5362 - Rev 1 page 17/30

6.2 Programmable output current control

The PPS feature of USB-PD 3.0 for load direct charging requires tight output current control. The power board isdesigned to support this feature with output current controlled by the MCU in a range from 0 to 100% with 50 mAsteps, as recommended by the USB Power Delivery specification.

Figure 18. VBUS_1 Output current vs. CC_VREF_1 Duty Cycle

0,000

0,500

1,000

1,500

2,000

2,500

3,000

3,500

0,000 0,100 0,200 0,300 0,400 0,500 0,600 0,700 0,800 0,900 1,000

Out

put c

urre

nt [A

]

Duty

Output current vs. CC_VREF_1 duty

Iout [A]

Figure 18 shows the setup with the power board limiting the output current and simulating the current steps of theUSB-PD PPS-I function from 50 mA up to 3 A, with incremental steps of 50 mA. Even in this case, the test resultsrelate to open loop operation, where the board output current is set by the PWM signal CC_VREF_x only. In thiscase, the MCU does not have its own additional feedback loop on the output current as it would in acomprehensive USB-PD application. This method provides a good indication of the precision of the power andcontrol circuits of the power board, and the diagram shows excellent linearity and monotonic behaviour of theoutput current versus the duty cycle.Figure 19 shows the waveform for PPS-I operation, where converter Buck1 is regulating the output current at1.5 A on a resistive load, while the output voltage is 5.55 V due to the effect of the load resistance. The referencePWM signal CC_VREF_1 has frequency 26 kHz with duty cycle 44.3 %.The other signal on the oscilloscope image is the I_SENSE_1 current feedback signal coming from the sensingcircuit, which is required by the error amplifier U5 to close the regulation loop. The D10-K (cathode) is now at alevel where the output current has the proper programmed value. In this case, the L5964 voltage loop is notworking and its error amplifier is not working, it is just delivering the maximum output current because the voltageloop is open.

AN5362Programmable output current control

AN5362 - Rev 1 page 18/30

Figure 19. Waveforms detail during PPS-I operation – Vin = 12 V, Iout = 1.5 A

• Legend: CH1: VBUS_1; CH2: I_SENSE_1; CH3: D10-K VOLTAGE; CH4: CC_VREF_1

Figure 20. Waveforms detail during PPS-I operation-2 – Vin = 12V, Iout = 3 A

• Legend: CH1: VBUS_1; CH2: D10-K VOLTAGE; CH3: VPHASE_1; CH4: V1_PWM

Similar traces were captured in Figure 20 for an output current of 3 A. It is possible to note the longer duty cycle ofthe CC_VREF_1 signal and the increased level of the current feedback signal I_SENSE_1. The D10-K signal isalso higher because of the higher programmed current.During constant output current operation, the converter output voltage has to be programmed at a value higherthan the expected maximum output voltage range; otherwise, the output voltage loop will limit the output voltage.Once operating in constant current mode, the converter behaves as a current source. Therefore, programming aproper value of the output voltage by the PPS-V function or by fixed output voltage flags implements overvoltageprotection that can prevent the converter from supplying the load with excessive voltage.

AN5362Programmable output current control

AN5362 - Rev 1 page 19/30

7 Operating temperature measurements

The operating temperature was measured using the internal temperature sensor, which provides a voltage that isinversely proportional to the junction temperature. Figure 21 shows how the junction temperature always remainsin a safe operating range, which helps guarantee long term operation.The temperature measurements were performed during efficiency testing of the converters working with the samevoltage and current on both channels. The ambient temperature was 27 °C.It is clear that the junction temperature depends on the cooling capability of the device. With proper cooling, theheat sink can be eliminated, or the cheaper L5964Q-V0Y version using the VQFPN-48 package can be used toreplace the tested L5964L-VYY version using the LQFP64 package with exposed pad up.

Figure 21. Vtj and Tj vs. Pout

0

20

40

60

80

100

120

0

0,2

0,4

0,6

0,8

1

1,2

1,4

1,6

0,0 10,0 20,0 30,0 40,0 50,0 60,0Tj

[°C]

VTj [

V]

Pout_total [W]

Vtj [V]

Tj [degC]

5V

5V

9V

9V

AN5362Operating temperature measurements

AN5362 - Rev 1 page 20/30

8 Bill of materials

Table 9. Bill of materials

Item Q.ty Ref. Part / Value Description Manufacturer Order code

1 2 C1, C2 1µF, 50V, ±10%Ceramic CapacitorMLCC - X7R, 1206[PCB 1210]

AVX 12065C105KAT2A

2 4 C24, C25, C27,C29 1µF, 50V, ±10% Ceramic Capacitor

MLCC - X7S, 1206 AVX 1206YZ105KAT2A

3 8C3, C4, C6, C7,C9, C17, C55,C62

100nF (0.1µF),50V, ±10%

Ceramic CapacitorMLCC - X7R, 0805 KEMET C0805T104K5RACTU

4 2 C33, C34 100nF (0.1µF),50V, ±10%

Ceramic CapacitorMLCC - X7R, 1206 KEMET C1206S104K5RACTU

5 5 C56, C57, C58,C59, C63

100nF (0.1µF),50V, ±10%

Ceramic CapacitorMLCC - X7R, 0603 MURATA GCJ188R71H104KA12D

6 5 C5, C12, C15,C18. C61

1nF (1000pF),50V, ±10%

Ceramic CapacitorMLCC - X7R, 0805 MURATA GCM216R71H102KA37J

7 3 C60, C64, C65 1nF (1000pF),50V, ±10%

Ceramic CapacitorMLCC - X7R, 0603 MURATA GRM033R71H102KA12D

8 1 C8 10µF, 10V, ±10% Ceramic CapacitorMLCC - X7R, 0805 MURATA GRM21BR71A106KA73L

9 1 C11 100µF, 50V,±20%

Ell. Capacitor -EEEFP1H101AP,dia. 8 x 10 mm

PANASONIC EEEFP1H101AP

10 2 C20, C21 6.8nF (6800pF),50V, ±10%

Ceramic CapacitorMLCC - NPO, 0805 MURATA GCM216R71H682KA37J

11 2 C22, C23 330pF, 50V,±10%

Ceramic CapacitorMLCC - NPO, 0805 MURATA GCJ216R71H331KA01J

12 2 C26, C28 56µF, 35V, ±20%ELCAP -PCV1V560MCL1GS,dia. 8 x 10 mm

NICHICON PCV1V560MCL1GS

13 2 C30, C31 47nF (0.047µF),50V, ±10%

Ceramic CapacitorMLCC - X7R, 0805 MURATA GCE21BR71H473KA01L

14 2 C39, C40 47nF (0.047µF),50V, ±10%

Ceramic CapacitorMLCC - GRM serries- COG, 0805

MURATA GRM21B3U1H473JA01

15 2 C32, C35 470µF, 25V,±20%

ELCAP -EEHZK1E471P, dia.10 x 10 mm

PANASONIC EEHZK1E471P

16 7C38, C42, C43,C46, C47, C48,C49

10nF (0.010µF),50V, ±10%

Ceramic CapacitorMLCC - X7R, 0805 MURATA GCM219R71H103KA37J

17 1 C41 10nF (0.010µF),50V, ±10%

Ceramic CapacitorMLCC - COG, 0805 MURATA GRM31M3U1H104JA01

18 1 C50 1.5nF (1500pF),50V, ±10%

Ceramic CapacitorMLCC - COG, 0805 MURATA GCD216R71H152KA01D

19 2 C51, C66 2.2nF (2200pF),50V, ±10%

Ceramic CapacitorMLCC - NP0, 0603 MURATA GCD188R71H222KA01D

AN5362Bill of materials

AN5362 - Rev 1 page 21/30


20 7

C10, C13, C14,C16, C19, C44,C45 NOTMOUNTED

- Ceramic CapacitorMLCC , 0805 - -

21 1 D2 Red LED, low current,0603 VISHAY TLMS1000-GS08

22 1 D3 NOTMOUNTED - SOD-323 - -

23 2 D4, D5 100V, 2AAutomotive PowerSchottky Rectifier,SOD-123Flat

ST STPS2H100ZFY

24 2 D6, D7 Yellow LED, low current,0603 VISHAY TLMY1000-GS08

25 10

D8, D10. D11,D12, D13, D14,D15, D16, D17,D18

100 V, 150mAGeneral PurposeSignal SchottkyDiode, SOD-323

ST BAT46JFILM

26 1 HS1 - Heat sink, 15x15x8(H) mm

FISCHERELECTRONIK

ICK SMD E15

27 1 J1 PITCH 5.0 mm -2-WAY Power-in connector PHOENIX

CONTACT MKDSN 1,5/ 2

28 3 J2, J4, J5 NOTMOUNTED - - - -

29 1 J3 2.54 mmSTRIP FEMALE 9 x2 Power connectorBOTTOM SIDE

SAMTEC -

30 2 J6, J7 2.54 mm STRIP FEMALE 8 x1 - TOP SIDE SAMTEC -

31 2 J8A, J8B 2.54 mm FEMALE/MALE 20 x4- BOTTOM SIDE SAMTEC -

32 2 J9, J10 2.54 mmSTRIP FEMALE 2 x1 pin - BOTTOMSIDE

SAMTEC -

33 1 L1 ACM12V CM Filter, 12 x 11mm H = 6 mm TDK ACM12V-701-2PL-TL00

34 2 L2, L3 4.7 µHShielded powerinductor, 4 x 4 mm H= 3 mm

COILCRAFT XAL4030-472ME

35 2 L4, L5 33 µHShielded powerinductor, 12x12 mm -H = 8 mm

COILCRAFT MSS1278T-333

36 8

Q1-2, Q1-1.Q2-1, Q2-2,Q3-2, Q3-1,Q4-2, Q4-1

2N7002DW Small signal mosfet,SOT-363 INFINEON 2N7002DW

37 8Q5A, Q5B, Q6A,Q6B, Q7B, Q7A,Q8B, Q8A

BC846BDW1T1G

Dual NPN BJT,SOT-363 ONSEMI BC846BDW1T1G


AN5362 - Rev 1 page 22/30

https://www.st.com/en/product/stps2h100zfy

https://www.st.com/en/product/bat46


38 18

R3, R9, R13,R14, R17, R18R19, R20. R23,R25, R29 R30,R32, R41, R42,R43 R53, R54NOT MOUNTED

- 0805 - -

39 8R4, R12, R15,R24, R26 R35,R104, R109

0R0, 1/8W, ±5%SMD STD FILMRES - 250ppm/°C,0805

VISHAY -

40 2 R2, R126 0R0, 1/4W, ±5%SMD STD FILMRES - 250ppm/°C,1206

VISHAY -

41 1 R1 820K, 1/8W,±5%

SMD STD FILMRES - 100ppm/°C,0805

VISHAY -

42 1 R5 10R, 1/4W, ±5%SMD STD FILMRES - 250ppm/°C,1206

VISHAY -

43 4 R55, R56, R60,R61 10R, 1/8W, ±5%


VISHAY -

44 12

R6, R7, R16,R28, R66, R68,R74 R77, R78,R79, R82, R83

100K, 1/8W,±1%


VISHAY -

45 2 R120, R125 100K, 1/10W,±5%


VISHAY -

46 4 R52, R67, R95,R106

100R, 1/10W,±5%


VISHAY -

47 1 R10 110K, 1/10W,±1%


VISHAY -

48 2 R31, R33 220K, 1/8W,±5%


VISHAY -

49 2 R72, R73 220R, 1/8W,±5%


VISHAY -

50 2 R86, R102 330R, 1/10W,±5%


VISHAY -

51 2 R8, R22, 560K, 1/8W,±1%


VISHAY -

52 2 R98, R114 560K, 1/10W,±1%


VISHAY -

53 2 R57, R71 10K, 1/8W, ±5%SMD STD FILMRES - 200ppm/°C,0805

VISHAY -


AN5362 - Rev 1 page 23/30



VISHAY -

55 4 R47, R51, R100,R107

10K, 1/10W,±1%


VISHAY -

56 1 R111 10K, 1/10W,±5%


VISHAY -


VISHAY -

58 2 R45, R49 12K4, 1/10W,±1%


VISHAY -

59 2 R99, R113 1K0, 1/10W,±1%


VISHAY -

60 2 R103. R112 1K0, 1/10W,±5%


VISHAY -

61 4 R44, R48, R62,R63

1K2, 1/10W,±1%


VISHAY -

62 5 R11, R84, R92,R93, R115

1K2, 1/10W,±5%


VISHAY -

63 2 R85, R94 1K8, 1/10W,±5%


VISHAY -

64 6 R64, R65, R75,R76, R80, R81 22K, 1/8W, ±5%


VISHAY -

65 2 R97, R110 22K, 1/10W,±1%


VISHAY -

66 8

R87, R89, R90,R91, R116,R117, R118,R119

27K, 1/10W,±5%


VISHAY -

67 2 R121, R124 33K, 1/10W,±1%


VISHAY -

68 2 R122, R123 36K, 1/10W,±1%


VISHAY -

69 1 R21 47K, 1/10W,±1%


VISHAY -


VISHAY -


AN5362 - Rev 1 page 24/30


71 2 R69, R70 4K7, 1/8W, ±5%SMD STD FILMRES - 250ppm/°C,0805

VISHAY -

72 1 R34 68K, 1/8W, ±5%SMD STD FILMRES - 250ppm/°C,0805

VISHAY -

73 2 R46, R50 8K66, 1/10W,±1%


VISHAY -

74 2 U2, U3 RGB LED CA SMD KINGBRIGHT AAA3528LSEEZGKQBKS

75 12

TP1, TP2, TP3,TP4, TP5, TP6TP7, TP8, TP9,TP10, TP11,TP12

- TEST POINT - PCBMETALLIZED HOLE - -

76 1 U1 3.5A

Monolithic dual step-down switchingregulator with LDO,LQFP-64

ST L5964L-VYY

77 2 U4, U5 GBP 2.7MHz,16V

Precision (200uV),rail-to-rail CMOSOp-Amp, single,SOT23-5L

ST TSX711ILT


AN5362 - Rev 1 page 25/30


https://www.st.com/en/product/tsx711

Revision history

Table 10. Document revision history

Date Version Changes

01-Jul-2019 1 Initial release.

AN5362

AN5362 - Rev 1 page 26/30

Contents

1 Main characteristics and board description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

2 Connectors and interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

3 Functional blocks and circuit descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

3.1 Power stages and buck converters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.2 Output voltage regulation loops. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.3 Output current regulation loops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

3.4 Overcurrent protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.5 Power good signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.6 Voltage monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.7 Temperature monitor and overtemperature protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.8 LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.9 LDO and additional functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4 Connecting the power board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

4.1 Operation with USB Type-C function board (AEK-USB-2TYPEC1) . . . . . . . . . . . . . . . . . . . . 11

4.2 Standalone operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

5 Fixed output voltage and efficiency at 12 Vdc input voltage . . . . . . . . . . . . . . . . . . . . . . .13

6 Operation with MCU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

6.1 Variable output voltage (PPS-V mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

6.2 Programmable output current control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

7 Operating temperature measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20

8 Bill of materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21

Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26

Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27

List of tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28

List of figures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29

AN5362Contents

AN5362 - Rev 1 page 27/30

List of tablesTable 1. AEK-POW-L5964V1 signals to and from the MCU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Table 2. Pin type legend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Table 3. Fixed output voltage selection table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Table 4. Variable output voltage selection table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Table 5. Signal LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Table 6. Connections for operation with MCU. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Table 7. Connections for operation with complete USB PD kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Table 8. Voltage measurements and efficiency calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Table 9. Bill of materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Table 10. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

AN5362List of tables

AN5362 - Rev 1 page 28/30

List of figuresFigure 1. AEK-POW-L5964V1 digitally controlled DC-DC converter with L5964 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Figure 2. Fixed output voltage feedback loop schematic-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Figure 3. Variable output voltage feedback loop for PPS-Voltage mode schematic-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Figure 4. Vout vs. Vx_PWM duty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Figure 5. Vx_PWM duty vs. Vout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Figure 6. Simplified schematic for constant output current feedback loop (Buck2, VBUS_0) . . . . . . . . . . . . . . . . . . . . . . 8Figure 7. AEK-POW-L5964V1 schematic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Figure 8. Power board plugged on MCU board. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Figure 9. Power board with MCU board and 2-port USB-PD interface board. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Figure 10. Overall efficiency vs. output current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Figure 11. Buck waveforms – Vin = 12.5V, Vbus_1 = 9 V @ 3 A, Vbus_0 = 5 V @ 3 A . . . . . . . . . . . . . . . . . . . . . . . . . 14Figure 12. Output voltage ripple - Vin = 12.5V, Vbus_1 = 9 V @ 3 A, Vbus_0 = 5 V @ 3 A . . . . . . . . . . . . . . . . . . . . . . . 14Figure 13. Buck waveforms – Vin = 12.5V, Vbus_1 = 9 V @ 3 A, Vbus_0 = 9 V @ 3 A . . . . . . . . . . . . . . . . . . . . . . . . . 15Figure 14. Power board plugged on MCU board. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Figure 15. VBUS_1 output voltage vs. V1_PWM duty cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Figure 16. Waveform details during PPS-V operation – Vin = 12 V, Iout = 1 A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Figure 17. Waveform details during PPS-V operation-2 – Vin = 12 V, Iout = 1 A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Figure 18. VBUS_1 Output current vs. CC_VREF_1 Duty Cycle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Figure 19. Waveforms detail during PPS-I operation – Vin = 12 V, Iout = 1.5 A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Figure 20. Waveforms detail during PPS-I operation-2 – Vin = 12V, Iout = 3 A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Figure 21. Vtj and Tj vs. Pout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

AN5362List of figures

AN5362 - Rev 1 page 29/30

IMPORTANT NOTICE – PLEASE READ CAREFULLY

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© 2019 STMicroelectronics – All rights reserved

AN5362

AN5362 - Rev 1 page 30/30

http://www.st.com/trademarks

Documents

Digitally controlled DC-DC converter with L5964 for ......• Input connector J1: is connected to the 12 Vdc power source and can accept an input voltage from 6 Vdc up to 26 Vdc. •