Texas Instruments UCC28221 User manual

User’s Guide
1
UCC28221 200-W Evaluation Module
(EVM)
User’s Guide

2
EVM IMPORTANT NOTICE (CATEGORY B)
IMPORTANT: TI is providing the enclosed HPA035A evaluation module under the following conditions:
This evaluation module (EVM) being provided by Texas Instruments (TI) is intended for use for ENGINEERING
DEVELOPMENT OR EVALUATION PURPOSES ONLY and is not considered by Texas Instruments to be fit
for commercial use. As such, this EVM may not be complete in terms of design and/or manufacturing related
protective considerations including product safety measures typically found in the end−product incorporating
the module. As a prototype, this product does not fall within the scope of the European Union Directive on
electromagnetic compatibility and on low voltage and therefore may not meet the technical requirements of the
directive. This EVM is not subject to the EU marking requirements.
DShould this EVM not meet the specifications indicated in the User’s Guide the EVM may be returned within
30 days from the date of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE
WARRANTY MADE BY TI AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR
STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY
PARTICULAR PURPOSE.
DThe user assumes all responsibility and liability for proper and safe handling of the EVM. The user
acknowledge that the use of the EVM could present serious hazards and that it is the user’s responsibility
to take all precautions for the handling and use of the EVMs in accordance with good laboratory practices.
Please be aware that the products received may not be regulatory compliant or agency certified (FCC, UL,
etc.). Due to the open construction of the product, it is the user’s responsibility to take any and all appropriate
precautions with regard to electrostatic discharge.
DNEITHER PARTY WILL BE LIABLE TO THE OTHER FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR
CONSEQUENTIAL DAMAGES.
DTI is currently dealing with various customers for products, and therefore our arrangement with the user will
not be exclusive.
DTI assumes no liability for applications assistance, customer product design, software performance,
or infringement of patents or services described herein.
DPlease read the User’s Guide and specifically the section in the User’s Guide pertaining to warnings and
restrictions prior to handling the product. This section contains important information regarding high
temperature and voltages which TI recommends to be read before handling the EVMs. In case of any doubt
regarding safety, please contact the TI application engineer.
DPersons handling the product should have electronics training and observe good laboratory practice
standards.
DNo license is granted under any patent right or other intellectual property right of TI covering or relating to
any combination, machine, or process in which such TI products or services might be or are used.
DThis Agreement is subject to the laws of the State of Texas, excluding the body of conflicts of laws and the
United Nations Convention on the International Sale of Goods, and will be subject to the exclusive
jurisdiction of the courts of the State of Texas.

3
DYNAMIC WARNINGS AND RESTRICTIONS
It is important to operate this EVM within the maximum input voltage ranges specified in Table 1.
Exceeding the specified input range may cause unexpected operation and/or irreversible damage to the EVM.
If there are questions concerning the input range, please contact a TI field representative prior to connecting
the input power.
Applying loads outside of the specified output range may result in unintended operation and/or possible
permanent damage to the EVM. Please consult the EVM User’s Guide prior to connecting any load to the EVM
output. If there is uncertainty as to the load specification, please contact a TI field representative.
During normal operation, some circuit components may have case temperatures greater than 50°C. The EVM
is designed to operate properly with certain components above 50°C as long as the input and output ranges are
maintained. These components include but are not limited to linear regulators, switching transistors, pass
transistors, and current sense resistors. These types of devices can be identified using the EVM schematic
located in the EVM User’s Guide. When placing measurement probes near these devices during operation,
please be aware that these devices may be very warm to the touch.
Mailing Address:
Texas Instruments
Post Office Box 655303
Dallas, Texas 75265
Copyright 2003, Texas Instruments Incorporated

SLUU173A - October 2003 − Revised December 2003
4UCC28221 200-W Evaluation Module (EVM)
UCC28221 200-W Evaluation Module (EVM)
Mike O’Loughlin System Power
ABSTRACT
The UCC28221 EVM is a 200-W power converter that converts 36-V to 76-V dc input voltage to a
regulated 12-V dc output in a two-channel interleaved forward converter topology.
Contents
1 Introduction 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 Caution 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 Electrical Characteristics 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 Performance 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5 Layout 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6 List of materials 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 Reference 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1 Introduction
The UCC28221 control device from Texas Instruments is used in a dual interleaved forward converter that
enables the power supply designer to reduce output current ripple and reduce magnetic size per power stage
allowing for improved transient response. The UCC28221 is a dual interleaved PWM controller with
programmable maximum duty cycle per channel up to 90% for interleaved forward and interleaved flyback
designs.
The power module has two isolated 100-W forward power stages operating at 500 kHz, which are operating
180 degrees out of phase with each other. This allows for smaller magnetic design and ripple current
cancellation on the output. The ripple current cancellation on the output allows for a larger allowable equivalent
series resistance (ESR) in your output capacitance.
The converter design also takes advantage of the on board 110-V internal JFET start up circuit of the UCC28221
that removes the need of an external trickle charge resistor for boot strapping. This circuit turns off after auxiliary
power is supplied to the device conserving power. This saves the power supply designer one component and
in high volume applications could be a considerable cost savings.
To correctly operate this EVM requires a minimum load of 50 W and a fan to keep the ambient temperature at
or below 40°C. Not keeping the EVM’s ambient temperature at or below 40°C could damage the EVM.
2 Caution
High voltage levels are present on this evaluation module whenever it is energized. Proper safety precautions
must be taken when working with this power module. Before handling, power must be removed from the EVM
and the input storage capacitance must be discharged below 50 V.

SLUU173A - October 2003 − Revised December 2003
5
UCC28221 200-W Evaluation Module (EVM)
+
+
+
2INA 7
OUTA
3GND 4INB 1N/C
6
VDD
5
OUTB
8
N/C
UCC27324D
U2
+ +
1
2
3
4
8
7 6
5
Figure 1. Typical Application Schematic

SLUU173A - October 2003 − Revised December 2003
6UCC28221 200-W Evaluation Module (EVM)
3 Electrical Characteristics
Table 1.
MIN TYP MAX UNITS
VIN 36 48 76
V
Output 11.4 12 12.6 V
POUT 50 200 W
Output ripple 500 mV
4 Performance
Figure 2
EFFICIENCY
vs
OUTPUT POWER
VOUT − Output Power −W
Efficiency−%
50 70 90 110 150 170 190
80
82
84
86
88
90
92
94
130
VIN = 36 V
VIN = 48 V
VIN = 76 V
CH. 3
100 mV/div
Figure 3
t − Time − 500 µs/div
OUTPUT RIPPLE VOLTAGE AT MAX LOAD
CH. 3 = VOUT

SLUU173A - October 2003 − Revised December 2003
7
UCC28221 200-W Evaluation Module (EVM)
Figure 4
CH. 3
1 V/div
t − Time − 500 µs/div
TRANSIENT RESPONSE WITH THE LOAD
STEPPED FROM 200 W TO 50 W
CH. 3 = VOUT
Figure 5
CH. 3
1 V/div
t − Time − 500 µs/div
TRANSIENT RESPONSE WITH THE LOAD
STEPPED FROM 50 W TO 200 W
CH. 3 = VOUT
M
4.4 A/div
CH. 2
4.4 A/div
CH. 1
4.4 A/div
Figure 6
t − Time − 1 µs/div
OUTPUT CURRENT RIPPLE CANCELLATION
(VIN = 36 V)
CH. 1 = IL2
CH. 2 = IL3
M = IL2 + IL3
M
4.4 A/div
CH. 2
4.4 A/div
Figure 7
CH. 1
4.4 A/div t − Time − 1 µs/div
OUTPUT CURRENT RIPPLE CANCELLATION
(VIN = 76 V)
CH. 1 = IL2
CH. 2 = IL3
M = IL2 + IL3

SLUU173A - October 2003 − Revised December 2003
8UCC28221 200-W Evaluation Module (EVM)
5 Layout
Figure 8. Top View
Figure 9. Bottom View

SLUU173A - October 2003 − Revised December 2003
9
UCC28221 200-W Evaluation Module (EVM)
6 List of Materials
The EVM list of materials is shown in Table 1.
Table 2. Evaluation Module List of Materials (HPA035)
REFERENCE QTY DESCRIPTION MANUFACTURER PART NUMBER
C1, C6 2Capacitor, ceramic, 1.0 µF, 16 V, X7R, 10%, 805 Std Std
C11, C12 2Capacitor, ceramic, 47 pF, 50 V, X7R, 5%, 603 Kemet C0603C470J5GACTU
C13, C15 2Capacitor, tantalum Chip, 47 µF, 16 V, 0.281 x 0.126 Vishay 595D476X9016C2T
C17, C18, C19, C20,
C21, C22 6Capacitor, ceramic, 1000 pF, 200 V, X7R, 10%, 1206 Vishay VJ1206Y102KXCA
C2 1 Capacitor, ceramic,0.47 µF, 50 V, X5R, 10%, 603 AVX 06036D474KAT
C23 1 Capacitor, ceramic, 0.01 µF, 500 V, X7R, 10%, 1206 Vishay VJ1206Y103KXEA
C24, C26, C27 3**Capacitor, OS−CON, 82 µF, 16 V, 40 mΩ, 20%, 8.3mm
(E7) Sanyo 16SVP82M
C28 1 Capacitor, ceramic, 0.01 µF, 25 V, X7R, 10%, 603 Kemet C0603C104K3RACTU
C29 1 Capacitor, ceramic, 680 pF, 16 V, X7R, 10%, 603 Std Std
C3 1 Capacitor, ceramic,180 pF, 50 V, X7R, 10%, 603 Std Std
C30 1 Capacitor, ceramic, 1 µF, 50 V, X7R, 20%, 1210 Std Std
C31 1 Capacitor, ceramic, 0.056 µF, 16 V, X7R, 10%, 603 Std Std
C32 1 Capacitor, ceramic, 0.1 µF, 50 V, X7R, 20%, 1210 Std Std
C33 1 Capacitor, ceramic, 0.47 µF, 16 V, X7R, 10%, 1206 Vishay VJ1206Y474KXJA
C4, C14, C16 3**Capacitor, MLP, 4.0 µF, 100 V ITW PAKTRON 405K100CS4G
C5, C25 2Capacitor, ceramic, 4.7 µF, 25 V, X7R, 10%, 1210 Vishay Std
C7, C9 2Capacitor, ceramic, 0.1 µF, 25 V, X7R, 10%, 603 Kemet C0603C104K3RACTU
C8, C10 2Capacitor, ceramic, 56 pF, 50 V, NPO, 5%, 603 Std Std
D1, D2, D13 3Diode, switching, 200 mA, 200 V, 330 mW, SOT23 Zetex BAS21
D12 1 Diode, zener, 9.1 V, 350 mW, SOT23 Diodes, Inc. BZX84C9V1T
D3 1 Diode, zener, 15 V, 350 mW, SOT−23 Diodes, Inc. BZX84C15
D4, D5, D6, D7 4Diode, schottky, 500 mA, 30 V, SOD123 ON Semiconductor MBR0530
D8, D9, D10, D11 4Diode, dual schottky, 20 A, 100 V, D2PAK/HS International Rectifier MBRB20100CTTRL
HS1, HS2, HS3, HS4,
HS5, HS6 6**Heatsink, surface mount heat sink, D2pak Aavid 573300
J1, J2 2Terminal block, 4 pin, 15 A, 5.1 mm, 0.80 x 0.35 OST ED2227
L1 1 **Inductor, SMD, 470 µH, 62 mA, 26 mΩ, 0.177 x 0.126 TDK NL453232T−471J
L2, L3 2**Inductor, SMT, 3.2 µH, 18 ARMS, 6.8 mΩ, 0.51 x 0.51 IHLP−5050FD−
RZ−3R3−M−01
Q1, Q2 2MOSFET, N-channel, 200 V, 0.030 Ω, D2PAK/HS VISHAY SUM65N20−30

SLUU173A - October 2003 − Revised December 2003
10 UCC28221 200-W Evaluation Module (EVM)
REFERENCE QTY DESCRIPTION MANUFACTURER PART NUMBER
R1 1 Resistor, chip, 15.0 kΩ, 1/10 W, 1%, 805 Panasonic ERJ−6ENF1502V
R12, R14 2Resistor, chip, 1 kΩ, 1/16 W, 1%, 603 Panasonic ERJ−3EKF1001V
R13, R15 2Resistor, chip, 5.23 Ω, 1/8 W, 1%, 1206 Std Std
R16, R17 2Resistor, chip, 100 Ω, 1/10 W, 1%, 805 Std Std
R18, R19 2Resistor, chip, 5.23 Ω, 1/10 W, 1%, 805 Std Std
R2 1 Resistor, chip, 22.6 kΩ, 1/10 W, 5%, 805 Std Std
R20, R21 2Resistor, chip, 0 Ω, 1/10 W, 5%, 805 Std Std
R22, R23 2Resistor, chip, 10 kΩ, 1/10 W, 1%, 805 Std Std
R25, R26, R27, R28,
R29, R30, R31, R32 8Resistor, chip, 7.5 Ω, 1 W, 5%, 2512 Std Std
R3 1 Resistor, chip, 604 kΩ, 1/10 W, 1%, 805 Panasonic ERJ−6ENF6043V
R33, R34 2Resistor, chip, 499 Ω, 1/8 W, 1%, 1206 Panasonic
R35 1 Resistor, chip, 3.57 kΩ, 1/16 W, 1%, 603 Std Std
R36 1 Resistor, chip,5.23 kΩ, 1/16 W, 1%, 603 Std Std
R37 1 Resistor, chip, 1.37 kΩ, 1/16 W, 1%, 603 Std Std
R38 1 Resistor, chip, 100 kΩ, 1/16 W, 1%, 603 Std Std
R4 1 Resistor, chip, 20.0 Ω, 1/8 W, 1%, 1206 Panasonic ERJ−8ENF10R0V
R5 1 Resistor, chip, 24.9 kΩ, 1/10 W, 1%, 805 Panasonic ERJ−6ENF2492V
R6, R24 2Resistor, chip, 750 Ω, 1/16 W, 1%, 603 Std Std
R7 1 Resistor, chip, 15.4 kΩ, 1/10 W, 1%, 805 Std Std
R8 1 Resistor, chip, 976 kΩ, 1/10 W, 1%, 805 Panasonic ERJ−6ENF9763V
R9 1 Resistor, chip, 5.36 kΩ, 1/10 W, 1%, 805 Std Std
T1, T2 2**Transformer, current sense, 10 A, 500 kHz, 1:50, 0.330
x 0.360 Pulse P8205T
T3, T4 2**SMT transformer, 2 Primary, 1 Secondary, 500 kHz,
103 W, LMAG = 35 µH, 0.787 x 0.984 Payton 50863
TP1 1 Adaptor, 3.5 mm probe clip ( or 131−5031−00), 0.2 Tektronix 131−4244−00
U1 1 Dual Interleaved PWM Controller With Programmable Max
Duty Cycle, SO16 TI UCC28221D
U2 1 High Speed Low Side Power MOSFET Driver, SO8 Texas Instruments UCC27324D
U3 1 Optocoupler, SO8 Motorola MOC206
U4 1 Adj Shunt Regulator, 100 mA, 36 V, SO8 TI TL431AID
−− 1 PCB, 0 In x 0 In x 0 In Any HPA035
NOTES: (1). These assemblies are ESD sensitive, ESD precautions shall be observed.
(2). These assemblies must be clean and free from flux and all contaminants. Use of no clean flux is not acceptable.
(3). These assemblies must comply with workmanship standards IPC−A−610 Class 2.
(4). Reference designators marked with an asterisk (’**’) cannot be substituted. All other components can be substituted with equivalent
MFG’s components.
7 References
Datasheet, UCC28220/1 Dual Interleaved PWM Controller with Programmable Maximum Duty Cycle, TI
Literature No. SLUS544