Texas Instruments Using the UCC27714EVM-551 (Rev. A) User guide

Using the UCC27714EVM-551

User's Guide

Literature Number: SLUUB02A

July 2015–Revised September 2015

User's Guide

SLUUB02A–July 2015–Revised September 2015

600-W Phase-Shifted Full-Bridge (PHSB) Converter

Based on the 600-W PHSB UCC28950 Converter

Cautions and Warnings

CAUTION:

Caution! Do not leave EVM powered when unattended.

HOT SURFACE:

Caution Hot Surface! Contact may cause burns. Do not touch. Please take the proper

precautions when operating.

HIGH VOLTAGE:

Danger High Voltage! Electric shock possible when connecting board to live wire. Board should

be handled with care by a professional. For safety, use of isolated test equipment with

overvoltage/overcurrent protection is highly recommended.

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600-W Phase-Shifted Full-Bridge (PHSB) Converter Based on the 600-W SLUUB02A–July 2015–Revised September 2015

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WARNING

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General Texas Instruments High Voltage Evaluation (TI HV EMV) User Safety Guidelines

Always follow TI's set-up and application instructions, including use of all interface components within their

recommended electrical rated voltage and power limits. Always use electrical safety precautions to help

ensure your personal safety and those working around you. Contact TI's Product Information Center

http://ti.com/support for further information.

Save all warnings and instructions for future reference.

WARNING

Failure to follow warnings and instructions may result in personal

injury, property damage or death due to electrical shock and burn

hazards.

The term TI HV EVM refers to an electronic device typically provided as an open framed, unenclosed

printed circuit board assembly. It is intended strictly for use in development laboratory environments,

solely for qualified professional users having training, expertise and knowledge of electrical safety risks in

development and application of high voltage electrical circuits. Any other use and/or application are strictly

prohibited by Texas Instruments. If you are not suitable qualified, you should immediately stop from further

use of the HV EVM.

1. Work Area Safety:

(a) Keep work area clean and orderly.

(b) Qualified observer(s) must be present anytime circuits are energized.

(c) Effective barriers and signage must be present in the area where the TI HV EVM and its interface

electronics are energized, indicating operation of accessible high voltages may be present, for the

purpose of protecting inadvertent access.

(d) All interface circuits, power supplies, evaluation modules, instruments, meters, scopes, and other

related apparatus used in a development environment exceeding 50Vrms/75VDC must be

electrically located within a protected Emergency Power Off EPO protected power strip.

(e) Use stable and non-conductive work surface.

(f) Use adequately insulated clamps and wires to attach measurement probes and instruments. No

freehand testing whenever possible.

2. Electrical Safety:

As a precautionary measure, it is always good engineering practice to assume that the entire EVM

may have fully accessible and active high voltages.

(a) De-energize the TI HV EVM and all its inputs, outputs and electrical loads before performing any

electrical or other diagnostic measurements. Revalidate that TI HV EVM power has been safely de-

energized.

(b) With the EVM confirmed de-energized, proceed with required electrical circuit configurations, wiring,

measurement equipment hook-ups and other application needs, while still assuming the EVM circuit

and measuring instruments are electrically live.

(c) Once EVM readiness is complete, energize the EVM as intended.

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WARNING

While the EVM is energized, never touch the EVM or its

electrical circuits, as they could be at high voltages capable of

causing electrical shock hazard.

3. Personal Safety

(a) Wear personal protective equipment e.g. latex gloves or safety glasses with side shields or protect

EVM in an adequate lucent plastic box with interlocks from accidental touch.

Limitation for safe use:

EVMs are not to be used as all or part of a production unit.

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Introduction

1 Introduction

This 600-W EVM was designed to demonstrate how the UCC28950 control device, UCC27524A and

UCC27714 gate drivers could be used in high-efficiency applications by achieving ZVS from 50% to 100%

load. To achieve this high efficiency the UCC28950 was designed to drive synchronous rectifiers on the

secondary side of the full-bridge converter. The UCC28950 also incorporates a burst mode and DCM

function to improve no-load efficiency. Please see UCC28950 data sheet for details.

The UCC277714 is a high-speed, high-voltage, high-side/low-side gate driver optimized for driving

MOSFETs in high-frequency, switch-mode power supplies that are based on bridge-type topologies. It

enables users to eliminate bulky gate-drive transformers in offline power supplies and achieve fast

switching of power MOSFETs by virtue of its low propagation delay and high-peak-drive current.

2 Description

The UCC27714EVM-551 is a 600-W phase-shifted, full-bridge converter that converts a 370-V

DC

to 410-

V

DC

input to a regulated 12-V output. This converter was designed to maintain ZVS down to 50% load.

2.1 Features

• ZVS from 50% to 100% load

• Higher Efficiency for 80-plus Applications

• Burst Mode/DCM Function (reduces no-load power dissipation to meet green mode requirements)

• Features UCC28950 controller, UCC27714 High-Voltage, High-Side/Low-Side Gate Driver,

UCC27524A Dual-Channel Low-Side Gate Driver and CSD19506KCS MOSFETs

2.2 Typical Applications for Phase-Shifted Full Bridge

• Server, Telecom Power Supplies

• Industrial Power Systems

• High-Density Power Architectures

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Electrical Performance Specifications

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3 Electrical Performance Specifications

Table 1. UCC27714EVM-551 Electrical Specifications

(1)

PARAMETER TEST CONDITIONS MIN TYP MAX UNITS

Input Characteristics

DC input voltage range 370 390 410 V

Maximum input current V

IN

= 370 V

DC

to 410 V

DC

2 A

Output Characteristics

Output voltage (V

OUT

) V

IN

= 370 V

DC

to 410 V

DC

11.4 12 12.6 V

Output current (I

OUT

) V

IN

= 370 V

DC

to 410 V

DC

50 A

Continuous output power (P

OUT

) V

IN

= 370 V

DC

to 410 V

DC

600 W

Load regulation V

IN

= 370 V

DC

to 410 V

DC

150 mV

I

OUT

= 5 A to 50 A

Line regulation V

IN

= 370 V

DC

to 410 V

DC

150 mV

I

OUT

= 5 A to 50 A

Output ripple voltage V

IN

= 370 V

DC

to 410 V

DC

200 mV

I

OUT

= 5 A to 50 A

Holdup time V

IN

stepped from 390 V

DC

to 0 V

DC

17 ms

P

OUT

= 500 W

System

Full load efficiency V

IN

370 V to 390 V, P

OUT

= 500 W 93% 94%

(1)

Operation ambient temperature full load, forced-air cooling 400 LFM at 25°C.

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CS

SYNC

OUTA

OUTC

OUTF

OUTE

VOUT

OUTF

OUTD

OUTB

GND

OUTE

PWRGND

CS

VOUT

390V/2A

PWRGND

J1

VIN+

TP6

PWRGND

0.47µF

C2

TP1

VBULK

1.0Meg

R12

1.0Meg

R3

10.0k

R17

HS1

Q3,Q4

3.01

R5

TP10

VBIAS

TP11

PWRGND

TP7

SYNC

GND

D9

MURS360T3G

Q1, Q2

10.0k

R25

6.19

R22

GND

D6

ES3BB-13-F

GND

1500µF

C4

1500µF

C5

GND

TP2

LOOP-

TP3

LOOP+

J2

VIN-

1

3

5

6

4

2

7

9

10

8

12

11

14

13

J5

1.0Meg

R14

3.01

R15

10.0k

R11

10.0k

R10

10.0k

R16

HS2

2

3

1

5

T1

PE-63587

D4

ES3BB-13-F

100k

R6

1.00k

R7

1µF

C11

1µF

C12

1000pF

C13

330µF

C3

3.01

R4

22µF

C24

1µF

C23

1µF

C18

Q6, Q7

48.7

R1

4.87k

R2

D1

1N4148W-7-F

10.0k

R24

6.19

R21

TP5

VOUT-

1500µF

C6

1500µF

C7

GND

49.9

R9

1500µF

C8

12V/50A

FC1

5.11

R29

Q1

SPP20N60C3

Q3

SPP20N60C3

3.01

R13

Q6

CSD19506KCS

D12

BAT54-7-F

D13

BAT54-7-F

L1

75PR8108

9

1

7

12

3

10

T2

75PR8107

Q7

CSD19506KCS

0.22µF

C1

1µF

C9

1µF

C10

TP4

VOUT+

1.00k

R8

J4

J3

HS3

1

2

3

4

5

6

7

8

L2

60PR964

ENA

1

INA

2

GND

3

INB

4

OUTB

5

VDD

6

OUTA

7

ENB

8

U3

UCC27524AD

Q2

SPP20N60C3

Q4

SPP20N60C3

HI

1

LI

2

VSS

3

NC/EN

4

COM

5

LO

6

VDD

7

NC

8

NC

9

NC

10

HS

11

HO

12

HB

13

NC

14

U1

UCC27714D

D10

MURS360T3G

D11

MURS360T3G

HI

1

LI

2

VSS

3

NC/EN

4

COM

5

LO

6

VDD

7

NC

8

NC

9

NC

10

HS

11

HO

12

HB

13

NC

14

U2

UCC27714D

GND

PWRGND

GND

OUTA

OUTB

OUTC

OUTD

Q8

MMBT2222A

Q5

MMBT2222A

7.15k

R20

7.15k

R26

PWRGND

GND

5.6V

D14

MMSZ5232B-7-F

5.6V

D15

MMSZ5232B-7-F

TP8

VBIAS2

TP9

PWRGND

22µF

C21

1µF

C20

5.11

R23

PWRGND

1µF

C22

1µF

C19

PWRGND

GND

7.15k

R27

GND

5.11k

R28

7.15k

R30

7.15k

R34

7.15k

R32

5.11k

R31

5.11k

R35

5.11k

R33

1µF

C17

PWRGND

1µF

C16

PWRGND

0.1µF

C14

0.1µF

C15

2.20

R18

2.20

R19

D3

BAT54-7-F

D5

BAT54-7-F

D7

BAT54-7-F

D8

BAT54-7-F

VBIAS2

VBIAS

GND

VCC1

1

GND1

2

INA

3

INB

4

INC

5

IND

6

NC

7

GND1

8

GND2

9

EN

10

OUTD

11

OUTC

12

OUTB

13

OUTA

14

GND2

15

VCC2

16

U4

ISO7240MDW

GND

Pins Description

1 SYNC

2 CS

3 OUTA

4 OUTD

5 OUTB

6 OUTC

8 OUTF

9 VBIAS

10 OUTE

7, 11, 12 GND

13, 14 VOUT

FC2

F1

Fuse, 2A, 250V, TH

i

SW

D2

MURS360T3G

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Schematic

4 Schematic

Figure 1. UCC27714EVM-551 Power Stage Schematic

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VREF

OUTE

OUTA

VOUT

SYNC

OUTD

OUTB

VREF

CS

OUTC

OUTF

VOUT

OUTC

OUTF

VBIAS

OUTE

OUTD

VREF

CS

SYNC

OUTA

VBIAS

VOUT

1µF

C1

GND

560pF

C4

No Pop

R12

GND

0

R17

No Pop

R16

0

R20

No Pop

R19

1.00k

R18

1.00k

R25

No Pop

R23

OUTB

No Pop

R27

0

R26

0.15µF

C2

12.1k

R3

2.37k

R2

2.37k

R1

56.2k

R8

0.1µF

C6

22.6

R15

0

R21

16.9k

R24

No Pop

R5

2.37k

R7

27.4k

R9

9.09k

R6

No Pop

C8

61.9k

R11

127k

R14

No Pop

R13

330pF

C7

13.3k

R10

12.1k

R4

825k

R29

No Pop

R28

5600pF

C3

1µF

C5

1.00k

R22

1

2

3

4

5

6

7

8

9

10

11

12

13

14

J1

DF11-14DP-2DS(52)

VREF

1

EA+

2

EA-

3

COMP

4

SS/EN

5

DELAB

6

DELCD

7

DELEF

8

TMIN

9

RT

10

RSUM

11

DCM

12

ADELEF

13

ADEL

14

CS

15

SYNC

16

OUTF

17

OUTE

18

OUTD

19

OUTC

20

OUTB

21

OUTA

22

VDD

23

GND

24

U1

UCC28950PW

VREF

EA+

EA-

COMP

SS/EN

DELAB

DELCD

DELEF

TMIN

RT

DCM

RSUM

ADEL

CS0

SYNC0

OUTF

OUTE

OUTD

OUTC

OUTB

OUTA

VDD

ADELEF

ADEL

ADELEF

CS0

DCM

GND

CS0

GND

Pins Description

1 SYNC

2 CS

3 OUTA

4 OUTD

5 OUTB

6 OUTC

8 OUTF

9 VBIAS

10 OUTE

7, 11, 12 GND

13, 14 VOUT

Schematic

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Figure 2. UCC27714EVM-551 Daughter Card Controller Schematic

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600-W Phase-Shifted Full-Bridge (PHSB) Converter Based on the 600-W SLUUB02A–July 2015–Revised September 2015

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-

Electronic or

Resistive

Load

+

Volt Meter 3

V

OUT

500V

DC Source

+ -

Volt Meter 1

V

IN

Volt Meter 2

I

IN

=V

RSHUNT1

/R

SHUNT1

TP5-

TP4+

- +

0-20v DC Bias

Supply

TP11

TP10

TP6 -

TP1 +

400 LFM Fan

J3

J4

J2

J1

+ -

0-20v DC Bias

Supply

TP8 TP9

R

SHUNT1

R

SHUNT2

Volt Meter 4

I

IN

=V

RSHUNT1

/R

SHUNT1

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Recommended Basic Test Equipment

5 Recommended Basic Test Equipment

Voltage Sources:

• 500-V

DC

Source Capable of 750 W

• Two DC Power Supply Capable of 20 V

Volt Meters: 4-V Meters

Output Load: 25-V/750-W Load

Precision Shunt Resistors for Measuring Efficiency:

• R

SHUNT1

= 5 A/100 mV

• R

SHUNT2

= 50 A/50 mV

Fan: 400 LFM

Recommended Wire Gauge:

• 18 AWG at V

IN

, V

IN

– to Source

• 8 AWG at V

OUT

, V

OUT

– to Electronic/Resistive Loads

6 Recommended Test Setup

Figure 3. Test Setup to Measure Efficiency

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Recommended Test Setup

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6.1 List of Test Points

Table 2. Test Points

TEST POINTS NAME DESCRIPTION

TP1 VBULK Input voltage positive (VIN+)

TP2 N/A Voltage loop injection point 1

TP3 N/A Voltage loop injection point 2

TP4 VOUT+ Output voltage positive

TP5 VOUT– Output voltage negative

TP6 PWRGND Input voltage ground (VIN–)

TP7 SYNC Synchronization input

TP8 VBIAS2 Bias 2 positive

TP9 GND2 Bias 2 negative

TP10 VBIAS Bias positive

TP11 GND1 Bias negative

7 Power On/Off Procedure

NOTE: It is important to follow the power up and power down procedure to ensure the EVM does

not get damaged.

This EVM was designed to show the performance of the UCC28950, UCC27714 and

UCC27524A in a phase-shifted, full-bridge and is not a standalone power supply. This EVM

does not included input under voltage lockout (UVLO) circuitry that would be present in a

standalone power supply.

1. The EVM was not designed to startup from 0-V input voltage. Please make sure the input voltage is in-

between 370 V and 410 V before applying the bias voltages.

2. Connect test setup similar to Figure 3 before applying power to the EVM.

3. Apply 370 V

DC

to 410 V

DC

to the input of the power converter with the 500-V

DC

source.

4. Set the 0-V to 20-V bias power supplies to 11 V, 12 V Maximum, (This powers the UCC28950 PWM

Controller).

5. When powering down the unit set the 0-V to 20-V DC supply to 0 V.

6. For safety before handling the EVM make sure there are not voltages present on the EVM greater than

50 V (Volt Meter 1).

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Test Data

8 Test Data

8.1 Line/Load Regulation and Efficiency Test Data

Table 3. Line/Load Regulations and Efficiency Test Data

SET V

IN

MEASURED V

IN

I

IN

V

OUT

I

OUT

EFFICIENCY

370 370.3 0.202 12.124 5.02 81%

370 370.0 0.302 12.123 8.02 87%

370 370.2 0.351 12.123 10.02 93%

370 370.2 0.857 12.123 25.03 96%

370 369.9 1.743 12.12 50.02 94%

390 390.4 0.192 12.123 5.02 81%

390 390.4 0.288 12.123 8.03 87%

390 390.3 0.334 12.123 10.03 93%

390 390.3 0.814 12.123 25.03 96%

390 390.0 1.654 12.120 50.07 94%

410 410.1 0.184 12.123 5.02 81%

410 410.1 0.276 12.123 8.02 86%

410 410.1 0.320 12.123 10.03 93%

410 410.0 0.776 12.122 25.04 95%

410 410.0 1.575 12.12 50.07 94%

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Frequency (Hz)

Gain (dB)

Phase (°)

100 200 500 1000 2000 5000 10000 100000

-44 -200

-24 -100

-4 0

16 100

36 200

56 300

D001D008D002

Gain

Phase

Frequency (Hz)

Gain (dB)

Phase (°)

100 200 500 1000 2000 5000 10000 100000

-44 -200

-24 -100

-4 0

16 100

36 200

56 300

D001D008D002

Gain

Phase

Output Power (%)

Efficiency (%)

20% 30% 40% 50% 60% 70% 80% 90% 100%

92%

93%

94%

95%

96%

D001

370V Efficiency

390V Efficiency

410V Efficiency

Output Power (%)

Efficiency (%)

10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

80%

82%

84%

86%

88%

90%

92%

94%

96%

D001

370V Efficiency

390V Efficiency

410V Efficiency

Test Data

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8.2 Efficiency Test Data

Figure 4. Efficiency 10% to 100% Load Figure 5. Efficiency 20% to 100% Load

8.3 Control Loop Gain and Phase Measurement

Figure 6. Loop Gain/Phase at 50 A, f

C

= 2 kHz, PM = 90 Figure 7. Loop Gain/Phase at 5 A, f

C

= 6 kHz, PM = 45

Degrees Degrees

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600-W Phase-Shifted Full-Bridge (PHSB) Converter Based on the 600-W SLUUB02A–July 2015–Revised September 2015

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Test Data

8.4 Transient Response

Startup CH3 = V

OUT

.

Figure 8. V

IN

= 390 V, I

OUT

= 0 A Figure 9. V

IN

= 390 V, I

OUT

= 5 A

Figure 10. V

IN

= 390 V, I

OUT

= 50 A

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Test Data

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8.5 Load Transient Response

CH4 = I

OUT

, CH3 = V

OUT

with 10-V

DC

Offset

Figure 11. V

IN

= 390 V I

OUT

= 50 A to 5 A Figure 12. V

IN

= 390 V, I

OUT

= Stepped from 5 A to 50 A

8.6 Output Ripple Voltage

CH3 = V

OUT

Figure 13. V

IN

= 390 V, I

OUT

= 50 A

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Test Data

8.7 Valley Switching

Loads Lower than 25 A, switch nodes valley switch

(CH1 = Q3g, CH2 = Q4g)

Figure 14. V

IN

= 390 V, I

OUT

= 5 A Figure 15. V

IN

= 390 V, I

OUT

= 5 A

(V

IN

= 390 V, I

OUT

= 5 A AB Valley Switching (Q3d = CH1)) (V

IN

= 390 V, I

OUT

= 5A CD Valley Switching (Q4d = CH3))

Loads Greater than 25 A, the switch nodes ZVS

Figure 16. V

IN

= 390 V, I

OUT

= 25 A Figure 17. V

IN

= 390 V, I

OUT

= 25 A

(V

IN

= 390 V, I

OUT

= 5 A AB Valley Switching (Q3d=CH1) ) (V

IN

= 390 V, I

OUT

= 5 A CD Valley Switching (Q4d=CH3))

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Test Data

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Figure 18. V

IN

= 390 V, I

OUT

= 50 A Figure 19. V

IN

= 390 V, I

OUT

= 50 A

(V

IN

= 390 V, I

OUT

= 5 A AB Valley Switching (Q3d=CH1)) (V

IN

= 390 V, I

OUT

= 5 A CD Valley Switching (Q4d = CH3))

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600-W Phase-Shifted Full-Bridge (PHSB) Converter Based on the 600-W SLUUB02A–July 2015–Revised September 2015

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Test Data

8.8 UCC27714 Gate Drive Performance

8.8.1 LI, LO propagation delay CH1 (VDD), CH2(LO), CH3(LI)

Figure 20. LI, LO Turn-On Propagation Delay Figure 21. LI, LO Turn-Off Propagation Delay

8.8.2 First LI LO Pulse at Power Up

(CH1 (VDD), CH2(LO), CH3(LI),

Drop in VDD at first LO pulse due to charging HB capacitor)

Figure 22. VDD Drop On First Bootstrap Capacitor Charging

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Test Data

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8.8.3 HI HO Propagation Delay

(CH2 (LO), CH1(HI), CH3(HO), CH4(VDD)

HO was measured with a 1:20 differential probe)

Figure 23. HI, HO Turn-On Propagation Delay

Figure 24. HI, HO Turn-Off Propagation Delay

18

600-W Phase-Shifted Full-Bridge (PHSB) Converter Based on the 600-W SLUUB02A–July 2015–Revised September 2015

PHSB UCC28950 Converter

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Test Data

8.8.4 HB (CH2), HI(CH1), HO(CH3), LO(CH4) During Power Up

1. HB and HO were measured with 1:20 differential probes.

2. HB charges up on first LO pulse.

3. HO will not become active on the first HI pulse.

• Includes a built-in fixed delay, please refer to the UCC27714 data sheet for details.

Figure 25. HB and HO Measurement During Start Up

8.8.5 Q3g(CH1), Q1g(CH3), Q4g(Ch2), Q2g(Ch4) During Soft-Start Power Up

1. VBIAS1 and VBIAS2 set at 11 V.

2. UCC28950 soft start capacitor C2 pulled to ground and then released to activate soft start.

3. Q1g and Q2g measured with 1:20 differential probes.

4. Q1g and Q2g are driven with HO pins from the UCC27714 U1 and U2.

There is roughly a 90us delay before the HO outputs become active.

This is a combination of the UCC28950’s burst mode function and UCC27714 built-in delay check the

device data sheets for delay details.

Figure 26. Q

g

Measurement During Startup

19

SLUUB02A–July 2015–Revised September 2015 600-W Phase-Shifted Full-Bridge (PHSB) Converter Based on the 600-W

PHSB UCC28950 Converter

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Test Data

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UCC28950 during soft start enters burst mode.

Please refer to the UCC28950 data sheet for details.

Figure 27. UCC28950 Burst-Mode Function

Q3g (CH1), Q1g (CH3), Q4g (Ch2), Q2g (V

OUT

) during soft-start startup.

Ch1 = 1:20 differential probe.

Figure 28. UCC28950 Burst-Mode Function During Soft Start

20

600-W Phase-Shifted Full-Bridge (PHSB) Converter Based on the 600-W SLUUB02A–July 2015–Revised September 2015

PHSB UCC28950 Converter

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Texas Instruments Using the UCC27714EVM-551 (Rev. A) User guide

Texas Instruments Using the UCC27714EVM-551 (Rev. A) User guide

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