Industry’s first 1200V Half Bridge Module based on GaN ... · 1.0E-09 1.0E-08 1.0E-07 1.0E-06 0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 A VDS, V Breakdown Voltage

Industry’s first 1200V Half Bridge Module based on GaN

technology

Outline

1200V Module based on GaN MISHEMT

Measurement results

Operational principles

Summary

Product Portfolio

RDSON 22mΩID (DC) 80ASMT pkg


RDSON 150mΩID (DC) 12A

Discrete devices and module - Wide range delivered power!

RDSON, mΩ

0.5 kW

3 kW

10 kW

The lowest RDSON GaN Device on the market

0 20 40 60 80 100 120 140 160

650V

Optimized for:

Tested in a Buck converter, 400V to 200V; CCM; hard switching

• Dead time - 75nS

• Inductor 340uH

VisIC GaN: V22N65A High Efficiency

92

93

94

95

96

97

98

99

100

0 1000 2000 3000 4000 5000 6000 7000 8000 9000

Effi

cie

ncy

[%

]

Power [W]

Efficiency vs load

100kHz

200kHz

300kHz

98.9% @ 100kHz

98.4% @ 200kHz

98.1% @ 300 kHz

• Liquid Cooling

• 28°C ambient temperature 22 mOhm 80 A 650V

Product Portfolio



RDSON 150mΩID (DC) 12A

Half Bridge Module RDSON 40mΩID (DC) 80A

Discrete devices and module - Wide range delivered power!

RDSON, mΩ

30 kW

0.5 kW

3 kW

10 kW

The only company worldwide with 1200V GaN

The lowest RDSON GaN Device on the market

0 20 40 60 80 100 120 140 160

1200V

650V

Optimized for:

VisIC advances GaN to 1200V range

with lower switching losses comparing to Si and SiC

Locked potential of GaN HEMT

Properties Si SiC GaN

Energy Gap, eV EG 1.12 3.2 3.4

Electron Mobility, cm2/Vs μ 1400 500 1200-1800

Breakdown Field, MV EB 0.3 3-5 5

Thermal Conductivity, W/cm τθ 1.5 3.7 3 - 4.5

Drift velocity, cm/s, 1e7 vs 1 1.4 2.5

Relative dielectric constant, εr 11.8 10 11

GaN

offers

the best properties for power

SiliconBsr

Bsr

E

ECFOM

2

2

Baliga FOM:

It is up to us to unlock it

Outline

1200V Module based on GaN

Measured results


Summary

Half Bridge module: VM40HB120D

40 mOhm

80 Amp continuous current, 320A peak

Push

Pull

HV+ MP HV-

Ceramic Cap

Enable

circuit

Balanc

e

Enable

circuit

Balanc

e

Push

Pull

64 mm

31

mm

GaN GaN

D-mode GaN MISHEMT, direct drive approach

(ALL Switch©)

Outline


Measured results


Summary

Results: Half Bridge CCM Waveform

Buck, continuous current mode (CCM), hard switching at 3.6kW output power


Switching frequency: 100kHz

Duty cycle: 50%

Inductor - 330uH inductance

𝑽𝒊𝒏 = 𝟖𝟎𝟎𝐕

𝐏𝒐𝒖𝒕 = 𝟑. 𝟔𝐤𝐖

Minimum current is 5.5A

Maximum current is 13A

Temperature of module

baseplate after 30 minutes of

work was measured as 45°c


Mid Point Voltage; 200V/div

800V/400V;

9.13Amp Pout

Inductor current; 5A/div

Results: Switching time

TRISE= 10 ns

TFALL= 4 ns

I = 32.6A

V = 800V

The lowest switching time for the class of performance

Current; 10A/div

Voltage, 200V/div

Results: Efficiency vs load

Total efficiency including inductor losses is above 97.5% at 3.5kW

CCM, hard switching; 100kHz frequency; 9A output current

97.6197.4897.2496.9196.6996.47

90

91

92

93

94

95

96

97

98

99

100

500 1000 1500 2000 2500 3000 3500 4000 4500 5000

Effi

cie

ncy

[%]

Power [W]

Test bench limited at time of test

Switching energy results:

VisIC 1200V HB module 1 leg: 800V

0

50

100

150

200

250

300

350

5 10 15 20 25 30

Ene

rgy

[µJ]

Current [A]

Eon energy (uJ)

Eoff energy (uJ)

Total Energy (uJ)VisIC 1200Vmodule

30.9W @ 100kHz

60.8W @ 200kHz

124W @ 400kHz

Results: Switching energy comparison

Combination of low Coss and fast switching times result inrecord switching loss of GaN device versus SiC :

HEMT vs MOSFET

Outline


Measurement results


Summary

Operational principle Two GaN transistors for each side

Push Pull

HV+ MP HV-

Ceramic Cap

Enable circuit

Balance

Enable circuit

Balance

Push Pull

64 mm

31

mm

GaN GaN

Operational principle Two GaN transistors for each side

HV+ MP HV-

64 mm

31

mm

Push Pull

V18

V22

NORMALLY ON

NORMALLY OFF

G1

G2

D2D1

C1

Push Pull

V18

V22

NORMALLY ON

NORMALLY OFF

G3

G4

D3

D4C2

Operational principle

QUESTIONS

How is the high voltage divided between

two serially connected GaN transistors?

How are the transistors balanced?

What happens with temperature

difference?

How is the high voltage divided

between two serially connected GaN

transistors?

Equally

How high voltage is divided

between two transistors?

0.0E+00

5.0E-07

1.0E-06

1.5E-06

2.0E-06

2.5E-06

3.0E-06

3.5E-06

4.0E-06

4.5E-06

5.0E-06

0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300

IDS

A

VDS, V

Breakdown Voltage measured on two transistors

Total current capacity 80A continuous current

VGS =-12V

VGS =-12V


between two transistors?

For two separate transistors: VGS =-12V

VGS =-12V

VGS =-12V

S

0.0E+00

5.0E-08

1.0E-07

1.5E-07

2.0E-07

2.5E-07

3.0E-07

3.5E-07

4.0E-07

4.5E-07

5.0E-07

5.5E-07

6.0E-07

0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300

IDS,

A

VDS, V

1.0E-09

1.0E-08

1.0E-07

1.0E-06

0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300

IDS

A

VDS, V

Breakdown Voltage measured on two transistors


between two transistors? For two separate transistors: Leakage is higher @ same voltage

1.0E-09

1.0E-08

1.0E-07

1.0E-06

0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300

IDS,

A

VDS, V

Breakdown voltage measured on one transistor

DEG

Si Substrate

Buffer

GaN

AlGaN

source draingate

Lateral GaN HEMT with spatially separated buffer and

channel could be designed to scaled up

Physics of GaN lateral connection

CDS

RDS

gM

RS RSGRDG

RD

RG

CDGCGS CG

DEG

Si Substrate

Buffer

GaN

AlGaN

source draingate




No

el

ectr

on

s h

ere

No

el

ectr

on

s h

ere

CDS

RDS

gM

RS RSGRDG

RD

RG

CDGCGS CG

RBUFFER




RBUFFER

CDS

RDS

gM

RS RSGRDG

RD

RG

CDGCGS CG

RBUFFER

CDS

RDS

gM

R

S

RS

G

RDGRD

RG

CDGC

GS

CG

Reduced COSS is a bonus


CDS

RDS

gM

RS RSGRDG

RD

RG

CDGCGS CG

CDS

RDS

gM

R

S

R

SG

RDGRD

RG

CDGC

GS

CG

RBUFFERRBUFFER

𝑪𝑶𝑺𝑺 =𝟏

𝟐𝑪𝑶𝑺𝑺𝟏 + 𝑪𝑶𝑺𝑺𝟐


QUESTIONS





difference?

Operational principles:

Follow me balance VD≈0V

+-

G2

G1

C1

D1

D2

VBD1=400V; VBD2=12V;

VCC

V22Normally OFF by direct drive

V18Normally ON


Follow me balance

Turning OFF:

+12V

0V

VD≈0V

VS2=VCC=+12V

VGS2=VG2-VS2= -12V

+-

G2

G1

C1

D1

D2

zero voltage signal G2

VGS on G2 becomes -12 relative to

source

Voltage at A starts to rise

Voltage at B starts to rise with delay,

due to intrinsic CGS’

When voltage on B reaches -7.5V, V18

closes

VD rises to 800V

If VGS1 >-12V, D2 conducts keeping

safe G1 voltage relative to source.


VCC

A

B

CGS

VD=800V

V22

V18


Follow me balance

Turning OFF:

+12V

0V

VD≈0V

Voltage

Vmid-Point ≈ VD /2

VS=VCC=+12V

VGS=VG-VS= -12V

G2

G1

C1

D1

D2

Safety net:

If point A jumps above 412V, D1

starts to conduct, reducing

voltage at A back to below 412V.


VCC

A

B

CGS

VD=800V

+-

Smooth rise/fall time

The lowest switching time for the class of performance

HARD SWITCHING CCM MODE DC/DC 800V/400V

VDS (200V/div)

IDS (5A/div)

Smooth rise/fall time

VDS (200V/div)

2uS/div

Additional Upside: known GaN chip, Mass production ready

97% efficiency at

5.8kW @ 350kHz,

VDS, 200V/div

Inductor Current ≈25A

73°C TJ on High Side

V22N65A switch.

BUCK DC/DC 400V/200V

CCM mode/hard switching conditions

TFALL=7.8nsTRISE=6.3ns


QUESTIONS





difference?


difference?

If one of transistors in pair is hotter?

Leakage current goes UP

Voltage drop goes DOWN

Transistors self-balance

Operational principles: Trace layout

Minimum Gate

inductance

Minimum Gate

inductance

HV+ HV-DC link

MP

Enable circuit

Enable circuit

Bus Power Loop

VGS HS

VGS LS

Thermal image

Thermal management

800V input, under 50°C at the hottest spot

100kHz, 800V Bus, 3.6kW

High side

TVS Diodes

Outline


Measured results


Summary


Switching frequency: 100kHz

Duty cycle: 50%

Inductor - 330uH inductance

𝑽𝒊𝒏 = 𝟖𝟎𝟎𝐕

𝐏𝒐𝒖𝒕 = 𝟑. 𝟔𝐤𝐖

Minimum current is 5.5A

Maximum current is 13A

Temperature of module

baseplate after 30 minutes of

work was measured as 45°c


Mid Point Voltage; 200V/div

800V/400V;

9.13Amp Pout

Inductor current; 5A/div

Summary

The experimental results of 1200V Half Bridge Module,

measured at 3.6kW power at continuous current mode

(CCM) hard switching, are presented

Demonstrated GaN module shows a great potential for

applications in the voltage range of 900 and 1200V

Future work is planned to complete measurements at

higher power level up to 20 kW and optimize module for

high frequency >300kHz and increase current and…

Now GaN starts to fulfill promises

made in 2010 Source: Yole Power GaN Report, November 2010

Thank You for Attention


Follow me balance

CGS role

+12V

0V

VD≈0V

Voltage

Vmid-Point ≈ VD /2

VS=VCC=+12V

VGS=VG-VS= -12V

G2

G1

C1

D1

D2

CGS in open state ~1uF

CGS in closed state ~700pF

C1 is 100pF

VA = 8.3V; VB = 0.83V; VGS1 =

-7.5V top GaN closed

VCC

A

B

CGS

VD=800V

+-

Documents

Industry’s first 1200V Half Bridge Module based on GaN ... · 1.0E-09 1.0E-08 1.0E-07 1.0E-06 0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 A VDS, V Breakdown Voltage