Texas Instruments UCC28C56EVM-066 User manual

User’s Guide
Using the UCC28C56EVM-066 High-Density 40-W
Auxiliary Power Supply for 800-V Traction Inverters
Table of Contents
1 General Texas Instruments High Voltage Evaluation (TI HV EVM) User Safety Guidelines............................................ 2
2 Description.............................................................................................................................................................................. 3
2.1 EVM Electrical Performance Specifications....................................................................................................................... 4
3 Schematic Diagram................................................................................................................................................................ 5
4 EVM Setup and Operation......................................................................................................................................................6
4.1 Recommended Test Equipment......................................................................................................................................... 6
4.2 External Connections......................................................................................................................................................... 6
4.3 EVM Test Points.................................................................................................................................................................8
5 Performance Data................................................................................................................................................................... 9
5.1 Efficiency Versus Load, 10% to 100% Load.......................................................................................................................9
5.2 Efficiency Versus VIN at 100% Load..................................................................................................................................9
5.3 Power Loss Versus Load, 10% to 100% Load................................................................................................................. 10
5.4 Load Regulation, 10% to 100% Load...............................................................................................................................10
5.5 Light Load Regulation, 0-mA to 200-mA Load................................................................................................................. 11
5.6 Line Regulation, Various Loads........................................................................................................................................11
5.7 Startup Waveforms...........................................................................................................................................................12
5.8 Shutdown Waveforms...................................................................................................................................................... 14
5.9 Output Voltage Ripple...................................................................................................................................................... 16
5.10 Steady State Switching Waveforms............................................................................................................................... 18
5.11 Transient Load Waveforms.............................................................................................................................................20
5.12 Over Current and Short Circuit Protections....................................................................................................................22
5.13 Stability Measurements..................................................................................................................................................24
5.14 Thermal Measurements................................................................................................................................................. 26
6 Assembly and Printed Circuit Board (PCB)....................................................................................................................... 30
7 Bill of Materials (BOM)..........................................................................................................................................................32
8 Revision History................................................................................................................................................................... 35
Trademarks
All trademarks are the property of their respective owners.
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1 General Texas Instruments High Voltage Evaluation (TI HV EVM) User Safety
Guidelines
WARNING
Always follow TI’s setup 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://
support/ti./com 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 nonconductive 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 a 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 connection, and other application needs, while still assuming the EVM circuit
and measuring instruments are electrically live.
c. After EVM readiness is complete, energize the EVM as intended.
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 (for example, latex gloves or safety glasses with side shields) or
protect EVM in an adequate lucent plastic box with interlocks to protect from accidental touch.
Limitation for safe use:
EVMs are not to be used as all or part of a production unit.
General Texas Instruments High Voltage Evaluation (TI HV EVM) User Safety Guidelines www.ti.com
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2 Description
The UCC28C56EVM-066 is a highly efficient primary-side controlled (using an AUX winding) flyback auxiliary
power supply for EV/HEV automotive power trains. The design provides 15.2-VTYP, 40-W output for 800-V
battery systems. It will deliver 40 W over the input voltage range from 125 V to 1000 V. The exact output
voltage is load dependent. From 40-V to 125-V input the design will supply 20 W. The EVM utilizes a 1700-V
silicon-carbide (SiC) MOSFET, making it ideal for 800-V battery systems.
The EVM is a 4-layer board with the top and bottom layers dedicated to signal and power routing. The two
inner layers are used only to route test points. In effect, this is a low-cost two-layer PCB. The controller and
it's associated power components are tightly compacted into a 50 mm x 86 mm area, highlighted by the
white rectangle show on the top silkscreen. Note, C1 is not included with the critical components because it's
considered to be part of the general VIN bypass capacitors in the system.
Every effort was made to use automotive qualified components. An automotive qualified 1700-V SiC MOSFET
is listed in the BOM. The flyback transformer should be automotive qualified with consultation from the given
transformer manufacturer.
Figure 2-1. UCC28C56EVM-066, HVP066A, Top View
Figure 2-2. UCC28C56EVM-066, HVP066A, Bottom View
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2.1 EVM Electrical Performance Specifications
Table 2-1. EVM Electrical Specifications, VIN = 800 Vdc, TA = 25°C (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
INPUT CHARACTERISTICS
VIN Input voltage range 40 800 1000 V
VVDD_ON VDD start voltage 17.6 18.8 20.0 V
VVDD_OFF VDD stop voltage 15.0 15.5 16.0 V
IIN_FL Input current at full load
VIN = 1000 V, IOUT = 2.7 A - 52 -
mA
VIN = 40 V, IOUT = 1.3 A - 590 -
IIN_NL Input current at no load
VIN = 1000 V - 0.8 -
mA
VIN = 40 V - 13 -
OUTPUT CHARACTERISTICS
100% load output 125 V ≤ VIN ≤ 1000 V - 15.2 -
V
VOUT 50% load output 40 V ≤ VIN ≤ 1000 V - 15.6 -
10% load output 40 V ≤ VIN ≤ 1000 V - 16.3 -
No load output 40 V ≤ VIN ≤ 1000 V - 19.3 -
IOUT VOUT load current range
125 V ≤ VIN ≤ 1000 V 0 - 2.7
A
40 V ≤ VIN ≤ 125 V 0 - 1.3
VOUT_REG Load regulation
250 mA ≤ IOUT ≤ 2.7 A - ±3.5 -
%
0 mA ≤ IOUT ≤ 200 mA 4 - 25
VOUT_RIPPLE PK-to-PK AC ripple
VIN = 1000 V, IOUT = 2.7 A, 1 MHz BWL - 400 -
mVPP
VIN = 50 V, IOUT = 1.3 A, 1 MHz BWL - 280 -
VOUT_SS_DELAY
VIN applied to when VOUT
begins rising from 0 V
VIN = 50 V, IOUT = 1.3 A - 255 -
ms
VIN = 1000 V, IOUT = 2.7 A - 230 -
VOUT_SS_trise VOUT soft start, rise time IOUT = 2.7 A - 10 - ms
VOUT_SS_OS VOUT soft start overshoot VIN = 1000 V, IOUT = 2.7 A - 3.5 - %
PMAX Maximum output power
125 V ≤ VIN ≤ 1000 V - - 40
W
40 V ≤ VIN ≤ 125 V - - 20
SYSTEMS CHARACTERISTICS
η Full load efficiency
VIN = 400 V, IOUT = 2.7 A - 87.4 -
%
VIN = 800 V, IOUT = 2.7 A - 86.1 -
fSW Switching frequency VIN = 800 V, IOUT = 2.7 A - 42.5 - kHz
ICS(OCL) Current sense limit RCS = 455 mΩ - 2.2 - A
fCO Bandwidth
VIN = 800 V, IOUT = 2.7 A - 625 -
Hz
VIN = 50 V, IOUT = 0.25 A - 3950 -
PM Phase Margin
VIN = 800 V, IOUT = 2.7 A - 105 -
deg
VIN = 50 V, IOUT = 0.25 A - 87 -
GM Gain Margin
VIN = 800 V, IOUT = 2.7 A - 40 -
dB
VIN = 50 V, IOUT = 0.25 A - 25 -
ΔTMAX Max. temp. rise over TPCB
T1 at 800 VIN, IOUT = 2.7 A, 40 W - 48.9 -
°C
T1 at 1000 VIN, IOUT = 2.7 A, 40 W - 55.3 -
Description www.ti.com
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3 Schematic Diagram
1.5pF
C4
1
2 3
Q1
HV_GND
130V
D2
160V
D3
1.0M
R1
130V
D4
22V
D5
Lpri=550 µH
130V
D6
HV_GND
2 1
1.6kV
D7
Npri:Nsec=10.2:1
Npri:Naux=8.5:1
18V
D9
130V
D8
HV_GND
Vout
100k
R8
Iso_GND
10uF
C7
AUX
200V
D13
60V
D12
1
2 3
Q3
Iso_GND
4.7uF
C13
22uF
C12
HV_GND HV_GND HV_GND HV_GND
10.0
R11
HV_GND Iso_GND
40V
D14
VREF 5V
RT/CT
3
1
2
Q4
OUTFB Gate_FET2.5V 39.2
R14
COMP
1
FB
2
CS
3
RT/CT
4
GND 5
OUT 6
VDD 7 VREF
8
U1
UCC28C56H-Q1
HV_GND
COMP
HV_GND
HV_GND
HV_GND
3
1
2
Q6
HV_GND
HV_GND
20.0k
R19
VREF
HV_GND
3
1
2
Q7
CS Rsense
0.91
R24
HV_GND
HV_GND
HV_GND
HV_GND
HV_GND
1
2
3
200V
D11
330nF
C17
127
R27
2.55k
R17
3.48k
R20
127
R16
100nF
C16
100
R4
R7
1000pF
C5
C6
20.0k
R13
10.0k
R6
40.2k
R12
15.0k
R23 4.02k
R22
2.00k
R26
1.00k
R21
324k
R18
1.00k
R5
1.0M
R3
2.2µF
C21
22pF
C23
0
R10
0.91
R25
HV_GND
10.0k
R9
47nF
C11
HV_GND
2 1
18V
D10
1
3 2
Q5
HV_GND
0.22uF
C2
1
6
5
3
8
9
10
11
NC 2
NC
4
NC 7
NC 12
T1
1uF
C18
160V
D1
0.22uF
C3
0.22uF
C1
3
1
2
Q8
1
2 3
Q2
+
1000uF
C9 +
1000uF
C10
44.2k
R15
62
R2
2200pF
C14
62
R28
22nF
C19
100pF
C20
100pF
C22
10uF
C8
1000pF
C15
2200pF
C24
VDD
VIN
Slope Compensation
Leading Edge
Current Filtering
Soft Start
HV Startup for VDD
HV Clamp
Iso_GND
AUX Supply
SW
Disable HV
Startup
Current
Voltage
Feedback
Sensing
Gate Drive
Blanking
Figure 3-1. UCC28C56EVM-066 Schematic.
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4 EVM Setup and Operation
Safety: This evaluation module is not encapsulated and there are accessible voltages that are greater than 50
VDC.
Isolation Input Transformer: A suitably rated 1:1 isolation transformer shall be used on the input(s) to this EVM
and be constructed in a manner in which the primary winding(s) are separated from the secondary winding(s) by
reinforced insulation, double insulation, or a screen connected to the protective conductor terminal.
WARNING
• If you are not trained in the proper safety of handling and testing power electronics please do not
test this evaluation module.
• 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.
• Caution Hot surface. Contact may cause burns. Do not touch!
• Read this user's guide thoroughly before making test.
WARNING
Caution: Do not leave EVM powered when unattended.
4.1 Recommended Test Equipment
1. VIN: DC power supply, 40 V to 1000 V output, capable of supplying up to 2 A
2. IOUT: Electronic load, capable of supporting at least 25 V with loads of 0 A to 3.0 A
3. Two DVMs measuring DC voltage
a. The DVM monitoring VIN+ must be able to withstand 1000 Vdc
4. Two DVMs measuring DC current
5. Oscilloscope: 4 channel, 500 MHz or better
a. Recommend three high voltage probes (rated to 1000 V CAT II, 2500 Vpk
b. Recommend one differential probe (±140V low range at 1/20, ±1400V high range at 1/200)
6. Thermal camera (optional) or thermocouple to measure T1 case temperature
4.2 External Connections
The UCC28C56EVM-066 EVM utilizes screw terminals for quickly connecting to VIN and VOUT. Connecting
the appropriate ammeters and voltmeters, as shown in Figure 4-1, allows accurate EVM efficiency and load
regulation measurements.
4.2.1 Setup and Connection of Test Equipment
1. Before connecting it to the EVM, turn on and adjust the VIN power supply to 50 V and set its current
limit to 1.5 A.
2. Turn off/disable the VIN power supply.
3. Connect the VIN power supply to J2 (VIN+) and J1 (GND).
4. Connect the variable load to J4 (VOUT+) and J3 (ISO_GND).
5. Set the load to the constant current (CC) and 0.25 A. Enable the load.
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4.2.2 Power On for the First Time
1. Verify VIN is off/disabled and no voltage is applied to the UUT.
2. Connect oscilloscope probes to VIN (20 V/DIV), VDD (4 V/DIV), and COMP (2 V/DIV).
3. Connect the differential probe to VO and ISO_GND at low range, 1/20 (scaled to 4 V/DIV).
4. Set the oscilloscope to single-trigger on VIN rising at 25 V. Set a time base of 50 ms/DIV.
5. Verify that the load is set to 0.25 A and is still enabled.
6. Turn on the VIN supply at 50 V. The oscilloscope should trigger and produce the waveforms shown in figure
5-6. If your result is the same as figure 5-6 then your EVM is functioning correctly, thus far. If your result
does not resemble figure 5-6 then stop. Troubleshoot the EVM at 50 VIN. Do not increase VIN until after
troubleshooting.
7. When VIN is 50 V only and with 0.25 A load, verify the following DC measurements at the test points:
a. VOUT+ (yellow TP) to ISO_GND ≈ 16.4 Vdc
b. V_AUX (white TP) to GND ≈ 18.7 Vdc
c. VDD (white TP) to GND ≈ 18.6 Vdc
d. VREF (white TP) to GND = 5.0 Vdc
e. FB (white TP) to GND = 2.5 Vdc
8. Turn off the VIN supply.
9. Increase VIN to 400 V with 1.3 A load and repeat steps 4 to 8. Verify that VOUT is OK at this condition.
10. Turn off the VIN supply.
11. Increase VIN to 800 V. At 800 V and 0.25 A load [and 2.7 A load] your result should be similar to figure
5-7 [and figure 5-8]. If your results are the same as figure 5-7 and 5-8 at 800 V then your EVM is 100%
functioning correctly and you can proceed with other tests.
Digital
Mul

meter
1000V Input
Capable
VIN
TP
GND
TP
VIN DMM
Digital
Mul

meter
for Voltage
Measureme
nt
VO TPISO_GND TP
VO DMM
VIN+
GND
Lab HV
DC Power
Supply
Digital
Mul

meter
for Current
Measureme
nt VOUT
ISO_GND
Electronic
Load
Digital
Mul

meter
for Current
Measureme
nt
Figure 4-1. UCC28C56EVM-066, Recommended Efficiency and Typical Test Setup
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4.3 EVM Test Points
Table 4-1 describes the various EVM test points, allowing easy access for connecting oscilloscope probes, DVM
test leads and wire connections to lab test equipment.
Table 4-1. Input, Output, Test Point (I/O/TP) Description
PIN I/O/TP COLOR DESCRIPTION MIN TYP MAX
J1 - Green GND - 0 V -
J2 I Green VIN+ 40 V 800 V 1000 V
J3 - Green ISO_GND - 0 V -
J4 O Green VOUT+ (depends on load) 14.5 V 15.5 V 20 V
VDD TP White Analog controller bias supply - 18.6 V -
VREF TP White Controller reference output 4.9 V 5 V 5.1 V
COMP TP White Error amplifier output 0 V - 5 V
VFB TP White Inverting input to the error amplifier 2.45 V 2.5 V 2.55 V
RT/CT TP White Fixed frequency triangle oscillator 0.9 VTYP 1.4 VPP 2.3 VPP
VIN TP Red Input voltage 40 V - 1000 V
V_AUXL TP White AUX voltage after a 10 ohm series resistor - 18.7 V -
V_AUX TP White AUX output voltage - 18.7 V -
VG TP White Voltage at the gate of the SiC MOSFET 0 V 18 V -
SWN TP Silver Switching node (bottom of the PCB) 0 V - VIN + 480 V
VO TP Yellow Output voltage 14.5 V 15.5 V 20 V
GND x5 TP Black GND - 0 V -
ISO_GND x2 TP Black Isolated GND - 0 V -
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5 Performance Data
5.1 Efficiency Versus Load, 10% to 100% Load
Load Current (A)
Efficiency (%)
0.25 0.5 0.75 1 1.25 1.5 1.75 2 2.25 2.5 2.75
50%
55%
60%
65%
70%
75%
80%
85%
90%
800 VIN
1000 VIN
Figure 5-1. UCC28C56EVM Efficiency vs Load
5.2 Efficiency Versus VIN at 100% Load
VIN (V)
Efficiency (%)
200 300 400 500 600 700 800 900 1000
75%
77.5%
80%
82.5%
85%
87.5%
90%
92.5%
95%
Figure 5-2. UCC28C56EVM Efficiency Versus VIN at 100% Load
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5.3 Power Loss Versus Load, 10% to 100% Load
Load Current (A)
Power Loss (W)
0.25 0.5 0.75 1 1.25 1.5 1.75 2 2.25 2.5 2.75
0
1
2
3
4
5
6
7
8
800 VIN
1000 VIN
Figure 5-3. UCC28C56EVM Power loss versus load
5.4 Load Regulation, 10% to 100% Load
Load Current (A)
Output Error (%)
0.25 0.5 0.75 1 1.25 1.5 1.75 2 2.25 2.5 2.75
-4%
-3%
-2%
-1%
0
1%
2%
3%
4%
800 VIN
1000 VIN
Figure 5-4. UCC28C56EVM Load Regulation, 10% to 100% Load
Performance Data www.ti.com
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5.5 Light Load Regulation, 0-mA to 200-mA Load
Load Current (A)
Output Error (%)
0 0.05 0.1 0.15 0.2
0
2%
4%
6%
8%
10%
12%
14%
16%
18%
20%
22%
24%
200 VIN
400 VIN
600 VIN
800 VIN
1000 VIN
Figure 5-5. UCC28C56EVM Load Regulation, No Load to 200-mA Load
5.6 Line Regulation, Various Loads
Input Voltage (V)
Output Error (%)
50 150 250 350 450 550 650 750 850 950
-5%
-4%
-3%
-2%
-1%
0
1%
2%
3%
4%
5%
0.5 A Load
1.3 A Load
2.0 A Load
2.7 A Load
Figure 5-6. UCC28C56EVM Line regulation, various loads
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5.7 Startup Waveforms
Figure 5-7. Start-Up 1: VIN = 50 V, Load = 0.25 A
Figure 5-8. Start-Up 2: VIN = 50 V, Load = 1.3 A
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Figure 5-9. Start-Up 3: VIN = 1000 V, Load = 0.25 A
Figure 5-10. Start-Up 4: VIN = 1000 V, Load = 2.7 A
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5.8 Shutdown Waveforms
Figure 5-11. Shutdown, VIN Removal: VIN = 50 V, Load = 0.25 A
Figure 5-12. Shutdown, VIN Removal: VIN = 50 V, Load = 1.3 A
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Figure 5-13. Shutdown, VIN Removal: VIN = 1000 V, Load = 0.25 A
Figure 5-14. Shutdown, VIN Removal: VIN = 1000 V, Load = 2.7 A
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5.9 Output Voltage Ripple
Figure 5-15. Output Voltage Ripple: VIN = 50 V, Load = 0.25 A
Figure 5-16. Output Voltage Ripple: VIN = 50 V, Load = 1.3 A
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Figure 5-17. Output Voltage Ripple: VIN = 1000 V, Load = 0.25 A
Figure 5-18. Output Voltage Ripple: VIN = 1000 V, Load = 2.7 A
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5.10 Steady State Switching Waveforms
Figure 5-19. Steady State: VIN = 50 V, Load = 0.25 A
Figure 5-20. Steady State: VIN = 50 V, Load = 1.3 A
Performance Data www.ti.com
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Figure 5-21. Steady State: VIN = 1000 V, Load = 0.25 A
Figure 5-22. Steady State: VIN = 1000 V, Load = 2.7 A
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Using the UCC28C56EVM-066 High-Density 40-W Auxiliary Power Supply for
800-V Traction Inverters
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5.11 Transient Load Waveforms
Figure 5-23. Transient Response: VIN = 50 V, Load = 100 mA to 650 mA at 25 Hz, 50% duty
Figure 5-24. Transient Response: VIN = 50 V, Load = 100 mA to 1.3 A at 25 Hz, 50% duty
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20 Using the UCC28C56EVM-066 High-Density 40-W Auxiliary Power Supply for
800-V Traction Inverters
SLUUCN1C – JUNE 2022 – REVISED DECEMBER 2022
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