Crystalspace P1U ”Vasik” Power Supply Power Supply... · · 2016-08-02Crystalspace P1U ”Vasik” Power Supply Overview ... P4 pinout, launch lock ... Symbol Parameter MIN

Crystalspace P1U ”Vasik” Power Supply

OverviewCrystalspace P1U power supply is thesmallest and the most advanced power supplyin the market. It suits well for densely packed1 and 2 unit CubeSats. It uses fast maximumpower point tracking boost converters tocharge integrated doubled battery pack.Battery output is fed through duplicatedconverters that can provide 3.3 V, 5 V, 12 V.Unregulated 3.7 V battery and regulatedbuses are available through individuallyselectable current limited and latch-upprotected switches. Pinouts, output voltagesand channels are changeable to user needs.Each sold unit has gone through acceptancetesting.

Features 7 mm thick and weighs only 80 g All critical components are doubled

(all regulators and batteries) Architecture flight tested on

successful ESTCube-1 satellite Up 10 W continuous solar input 3 Ah / 11 Wh of battery with double

under- and overvoltage protection 3 voltage rails + unregulated 3.7 V

battery rail 6 outputs with separate current limits,

protection and controllable switching All voltages are monitored Remove-Before-Flight pin connection RS485, RS422, UART or I2C

controlled Compatible with CubeSat Kit and

other standard components

Available options Doubled battery pack: 6 Ah / 22 Wh, with

13 mm thickness and 140 g weightPerformance

90% input converter efficiency Power consumption: 15 mW Regulated voltage rails with 4 W

guaranteed outputProduct Properties

Dimensions: 96 mm x 90 mm x (7 or 13) mm

Temperature range (excluding batteries) −40°C to 85°C

Mass without connector: 80 g IPC-A-610 Class 3 assembly Vibration and shock tested Thermal vacuum tested

Rev 1.2 Crystalspace OÜ,Ujula 1A, Tartu, Estonia

Table of Contents

About this Document .............................................................................................................................. 3

2. Quality Control, System Testing and Calibration ............................................................................... 3

3. System overview ................................................................................................................................ 4

3.1. Battery parameters ....................................................................................................................... 5

4. Interfaces ............................................................................................................................................ 6

4.1. Main Connector (P1 & P2) .......................................................................................................... 6

4.2. Communication Connector (P3) .................................................................................................. 7

4.3. Launch Lock connector (P4) ....................................................................................................... 8

4.4. Solar Cell Inputs (P5-P10) .......................................................................................................... 9

5. Communication ................................................................................................................................ 10

5.1. Frame format ......................................................................................................................... 10

5.2. List of Commands' ................................................................................................................. 11

5.3. Watchdog timer ..................................................................................................................... 13

6. Mechanical drawing ......................................................................................................................... 14

7. P1U Control Software ...................................................................................................................... 15

Version .................................................................................................................................................. 16

List of figuresFigure 1: Internal block diagram............................................................................................................4Figure 2: Connector placement (top view).............................................................................................6Figure 3: Mechanical drawing in millimeters......................................................................................14

Tabelite registerTabel 1: Internal characteristics..............................................................................................................4Table 2: Battery parameters....................................................................................................................5Table 3: P1 pinout, main connector........................................................................................................7Table 4: P2 pinout, main connector........................................................................................................7Table 5: P3 pinout, communication connector.......................................................................................7Table 6: P4 pinout, launch lock connections..........................................................................................8Table 7: Input parameters.......................................................................................................................9Table 8: Input connectors pinouts..........................................................................................................9Table 9: Frame......................................................................................................................................10Table 10: Interface command list 2......................................................................................................11Table 11: Interface command list 2 (Continues)..................................................................................12

Crystalspace P1U [email protected] www.crystalspace.eu

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mailto:[email protected]



http://www.crystalspace.eu/


1. About this Document This document gives overview of Crystalspace power supply unit P1U. Document describes systemsinterfaces, electrical and mechanical characteristics, tests done on the system and how to use it inyour own satellite.

2. Quality Control, System Testing and CalibrationCrystalspace will perform list of tests and calibrations before sending the final product to thecustomer. Performed tests will verify that the customer always gets high quality product, reduce theamount of tests and calibrations that the customer would have to perform and reduces the time ittakes user to start using our product. Crystalspace will give certificate with all its products that listsall the tests that were done on the system.

Following tests are performed with P1U:

Vibration test

Shock test

Thermal vacuum test


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3. System overview

P1U power supply is a high efficient maximum power point tracking (MPPT) power supply. Solarpanel input is directly converted to battery voltage level by MPPT converter. Our MPPT convertergets highest efficiency even in low light or highly dynamic environments. Power for doubled batterypack is converted to different voltages available from the power supply.

Microcontroller used in the power supply is an Industrial grade FRAM series microcontroller. Thisprocessor uses radiation tolerant Ferroelectric RAM for storing code, runtime variables and longterm constants. Power supply has its own watchdog timer that resets microcontroller on halt. Powersystem restart does not restart other powered systems or watchdog timers.

Figure 1: Internal block diagram

Symbol Parameter MIN TYP MAX Unit

Pq System power consumption 20 mW

rSystem energy efficiency from input to

output80%

Tabel 1: Internal characteristics


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3.1. Battery parameters

Two lithium ion battery cells are used in parallel. Each cell is individually current limited in bothdirections. Cells are also over- and undervoltage protected by microcontroller and separatemonitoring circuits. Battery voltages and currents are monitored. Battery heater and temperaturemeasurement are provided. Heater can be controlled automatically or via commands. Automaticheater has safety control system. Extra 2 batteries can be optionally added.

Batteries are covered with kapton tape and glued to the board with Scotch-Weld epoxy.

Symbol Parameter MIN TYP MAX Unit

Vbatt Battery voltage 3.3 3.7 4.2 V

Qbatt Cell capacity 1500 mAh

IbattSingle battery current limit (both directions)

4 A

tbatt Safe battery operating temperature 0 +45 °C

Table 2: Battery parameters


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4. Interfaces

This section describes P1U interfaces. Main connector is compatible with CubeSat kit to allowintegration with wide range of systems. Connector placement from top view is on Figure 2.Connectors are numbered and pin number one is marked. Four mechanical mounting holes in thecorners are grounded.

P1, P2 – Main connector;

P3 - Communication connector;

P4 – Launch lock connector;

P5-P10 – Solar cell inputs

4.1. Main Connector (P1 & P2)

All power supply outputs are connected to the main connector. Main connector is two pieces of 2row 52 pin connector, with 2,54 mm pin pitch. Connectors can be user supplied, Samtec HTSW-126-07-F-D, SSW-126-01-G-D or SSQ-126-03-G-D.

Three voltage rails are available: 3,3 V, 5 V and 12 V. Output power on each rail is 4 W. All railshave doubled regulators with separate current limiters and latch up protection. All output rails aremonitored.

Each voltage rail and unregulated battery voltage is fed to the system through switchable protectioncircuit. The system has total of 6 output switches. Two for 3,3 V, two for 5 V, one for 12 V and oneswitch for unregulated battery voltage. Unregulated battery voltage is available with current up to 2A.


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Figure 2: Connector placement (top view)








Switches have preflight selectable current limiters and latch up protection. Output voltage andovercurrent is monitored. All switches can be configured to turn on after launch or via commandsduring mission. Commanding output switches can be used to turn on payload or restart systems.

Table 3: P1 pinout, main connector

Pin Description34 5 V output 039 UART RX / RS-485 inverting40 UART TX / RS-485 non-inverting41 Clock (CLC)42 Chip Select (CS)

Table 4: P2 pinout, main connector

Pin Description27 3.3 V output 128 3.3 V output 033 5 V output 125 5 V output 047 12 V output

45, 46 Unregulated battery voltage output (Vbat)29, 30, 31, 32 Ground

4.2. Communication Connector (P3)

Communication connector can be used to communicate with power system microcontroller and sendit commands. Connector is DF13 series connector with part number DF13-6P-1.25DS(20).

Table 5: P3 pinout, communication connector

Pin Description1 3,3V UART Receive / RX2 Internal 3,3 V3 Do not connect4 Do not connect5 Ground6 3,3V UART Transmit / TX


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4.3. Launch Lock connector (P4)

Launch lock connector must be connected with remove-before-flight pin and deployment switches.If the signals don’t enable the satellite - all converters and outputs are switched off. Both signalshave pull-up resistors to 3.3 V and are debounced. Connector is DF13 series connector with partnumber DF13-4P-1.25DS(20).

Table 6: P4 pinout, launch lock connections

Pin Name Description1 GND Ground2 Enable Must be disconnected from ground to turn on the

satellite3 Disable Must be connected to ground to turn on the

satellite4 GND Ground


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4.4. Solar Cell Inputs (P5-P10)

There are 12 solar cell inputs grouped to two maximum power point tracking (MPPT) converters. Allsolar cell inputs are fed through separate ideal diodes.

Optionally another 8 solar cell inputs can be added to the bottom side in the expense of increasedthickness.

Table 7: Input parameters

Symbol Parameter MIN TYP MAX UnitVin Solar input voltage 1.7 2.5 5 VIin MPPT converter maximum current 1 A

Solar panel inputs are connected to six connectors (P5 - P10), one for each satellite side. The connectors are 0.5mm pitch flat flex cables or 4 pin Hirose DF13 connectors. DF13 connector part number is DF13-4P-1.25DS(20).

Table 8: Input connectors pinouts

Pin number SignalFlat flex 0.5 DF13

3 2 Solar cell input 14 3 Solar cell input 2

1, 2, 5, 6 1, 4 Common ground


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5. Communication

Board interfaces over UART, SPI, RS-422 or RS-485 bus. Bus operates with 8 data bits and 1 stopbit at baud of 115200. All data is sent over Modbus ASCII communication protocol.

5.1. Frame format

Table 9: Frame

Name Length(byte)

Function

Start 1 Frame starts with a colon. ASCII value is 0x3A.

Address 2 Receiver address. Default is 0x33.

Function code 2 According to table below

Data n Data is in ASCII, numbers are sent in hexadecimal form (base 16). Data length is according to the command.

LRC 2 Longitudinal redundancy check value in hexadecimal

To request information or change setting of the board a request must be sent. The board then answerswith required data or confirmation.

All commands reply. Commands where reply is not specified, the system replies with empty data. Ifcommand cannot be understood system will reply with ‘?’.

When replying with information all numbers are represented in hexadecimal (2 byte variable will be4 hexadecimal characters long). All measurements return in mV, mA or degrees in Celcius.

Boolean datatype (bool) can have values ‘0’ or ‘1’.


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5.2. List of Commands'

Table 10: Interface command list 2

Description Command Data Comments

Get housekeeping data

0x00 - ---reply-- int16_t bus_voltage

int16_t solar_current0int16_t solar_current1int8_t battery_tempint16_t bootcountint16_t latchup[6]

-

Enable all regulators andoutputs

0x01 - Except internal

Disable all regulators andoutputs

0x02

Get solar inputinformation

0x10 - ---reply-- int16_t bus_voltage;

int16_t current0;int16_t current1;

-

Get battery information

0x20 - ---reply-- int16_t voltage0

int16_t current0int16_t voltage1int16_t current1int8_t enable

Positive current indicates charging.

Enable mask, 1=on, 0=off,MSB [0,0,0,0,0,In0,In1,Out] LSB

Set battery enable 0x21 int8_t enable Bitmask is same as get information output.

Reset error counts. 0x61 - -Initialise watchdog timer 0x70 int16_t time; Time in ms. 0 to disable.

Reset watchdog timer 0x71 - -


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Table 11: Interface command list 2 (Continues)

Description Command Data Comments

Get regulator information

0x30--reply-- int16_t voltage_3v3_0

int16_t voltage_3v3_1int16_t voltage_5v_0int16_t voltage_5v_1int16_t voltage_12v_0int16_t voltage_12v_1int16_t voltage_int_0int16_t voltage_int_1int8_t enable

Enable mask, 1=on, 0=off.Bit order is the same as output voltages.

Set regulator enable 0x31 int8_t enable Bitmask is same as get information output.

Get output information

0x40 - ---reply-- int16_t voltage_3v3_0;

int16_t voltage_3v3_1;int16_t voltage_5v_0;int16_t voltage_5v_1;int16_t voltage_12v;int16_t voltage_bat;int8_t enable;

Enable mask, 1=on, 0=off.Bit order is the same as output voltages. Two most significant bits are 0.

Set output enable 0x41 int8_t enable Bitmask is same as information output.

Get temperatures

0x50 - ---reply-- int8_t battery;

int8_t processor;int8_t heater;

Heater:0 - off1 - on2 - automatic

Set heater 0x51 int8_t heater -

Get errors

0x60 - ---reply-- int16_t bootcount;

int16_t out_latchup[6];int16_t reg_latchup[8];int16_t bat_overcurrent[3];

Variables that show latchup counts.Output and regulator arrays have same arrangement as information replies (0x40, 0x30, 0x20).


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5.3. Watchdog timer

Power supply has a internal watchdog timer that can be used as a protection for on board computer.After initializing the timer it must be cleared every set amount of time. If on board computer shouldfreeze and not clear the watchdog, power supply will restart the system. This is an useful safetyfeature against code bugs.

Watchdog timer not initialized by default. To enable watchdog initialize it with desired time. Ifwatchdog timer has not been reset by specified time the power system resets all outputs and enablesall outputs that were enabled before. Watchdog timeout resets watchdog, and must be reset inwatchdog time.


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6. Mechanical drawing

Metric mechanical drawing, all dimensions are in mm. Main connectors are two pieces of 52 pinstwo row connectors.

Figure 3: Mechanical drawing in millimeters


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7. P1U Control Software Control software is a PC program meant for communicating with P1U module. Control softwarepurpose is to ease the system set up and calibration time. Software supports both Windows andLinux based computers.


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Version

Version Description Date1.0 Initial release. 2014-05-141.1 Command protocol change, added parameters 2014-12-121.2 All sections where updated & new ones added (Testing, P1U

Control Software)2015-01-25


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Documents

Crystalspace P1U ”Vasik” Power Supply Power Supply... · · 2016-08-02Crystalspace P1U ”Vasik” Power Supply Overview ... P4 pinout, launch lock ... Symbol Parameter MIN