Using the UCC24610EVM-563 User's Guide Literature Number: SLUU434 August 2010
User's Guide SLUU434 – August 2010 5-V, 25-W Flyback Converter With Secondary-Side Synchronous Rectification 1 Introduction The UCC24610EVM-563 evaluation module is a 25-W off-line Discontinuous Mode (DCM) flyback converter providing an output voltage of 5 V at 5-A maximum load current, operating from a universal AC input.
Description www.ti.com 2.1 Applications The UCC24610 is suited for use in isolated off-line systems requiring high efficiency and advanced fault protection features including: • 5-V AC-to-DC Adaptors • Housekeeping and Auxiliary 5-V Bias Supplies • Low-Voltage Rectification Circuits 2.2 Features The UCC24610EVM-563 features include: • Isolated 5-V, 25-W Output • Universal Off-Line Input Voltage Range • Exceeds Energy Star™ EPS Version 2.
Electrical Performance Specifications 3 www.ti.com Electrical Performance Specifications Table 1. UCC24610EVM-563 Electrical Performance Specifications PARAMETER NOTES AND CONDITIONS MIN NOM MAX UNITS Input Characteristics VIN Input voltage IIN Input current VUVLO Brown out 85 265 VIN = 115 VRMS, IOUT = 5 A 0.6 VIN = 115 VRMS, IOUT = 0 A 0.03 IOUT = 5 A VRMS A 69 V Output Characteristics VOUT Output voltage VIN = 85 VRMS to 265 VRMS, IOUT = 0 A to 5 A 4.5 5 5.
Schematic www.ti.com Schematic + + + + + + 4 Figure 1.
Schematic 4.1 www.ti.com Circuit Description Diode bridge D1, input capacitor C5, transformer (a.k.a. flyback inductor) T1, HV MOSFET Q2, UCC28610 controller U3, synchronous rectification MOSFET Q1, output capacitors C8, C9, and C10 form the power stage of the converter. Note that the UCC28610 U3 is part of the power stage. This is because the DRV and GND pins carry the full-peak primary-side current of the converter.
EVM Test Set Up www.ti.com 5 EVM Test Set Up Figure 2 shows the equipment set up when measuring the input power consumption during no load. Notice the addition of the 10-Ω shunt resistor in Figure 2. During the no-load test, the power analyzer should be set for long averaging in order to include several cycles of operation and an appropriate current scale factor for using the external shunt must be used. Figure 3 shows the basic test set up recommended to evaluate the UCC24610EVM-563 with a load.
EVM Test Set Up 5.2 www.ti.com Recommended Test Set Up for Operation Without a Load AC SOURCE LINE NEUTRAL POWER METER + - + VHI VLO AHI ALO AEXT 10 TEXAS INSTRUMENTS Figure 2. Recommended Test Set Up Without a Load.
EVM Test Set Up www.ti.com 5.3 Recommended Test Set Up for Operation With a Load AC SOURCE LINE NEUTRAL POWER METER + - + VHI VLO AHI ALO AEXT DMM V 1 + - TEXAS I NSTRUMENTS ELECTRONIC LOAD + + - - DMM A 1 Figure 3. Recommended Test Set Up With a Load.
EVM Test Set Up 5.4 www.ti.com List of Test Points Table 2. Test Point and Connector Functional Descriptions TEST POINT 10 NAME DESCRIPTION TP1 Vout+ Output voltage of EVM; this designator is not populated with a pin in order to facilitate tip and barrel output ripple voltage measurements in conjunction with TP3, Vout-. TP2 PGND Primary side power ground. Use this pin as a reference for TP15, VGG.
Test Procedure www.ti.com 6 Test Procedure All tests should use the set up as described in Section 5 of this user’s guide. The following test procedure is recommended primarily for power up and shutting down the evaluation module. Never leave a powered EVM unattended for any length of time. 6.1 Applying Power to the EVM 1. Set up the EVM as shown in Section 5 of this user’s guide. (a) If no-load input power measurements are to be made, set the power analyzer to long averaging and external shunt mode.
Test Procedure 6.4 www.ti.com Output Voltage Ripple 1. Expose the ground barrel of the scope probe. Insert the tip of the probe into the plated via located on the VOUT+ pad of the EVM (TP1) and lean the probe so that the exposed ground barrel is resting on the test point on the Vout- pad of the EVM (TP3) for a tip and barrel measurement as shown in the example depicted in Figure 4. 2. Apply power to the EVM per Section 6.1. 3. Monitor the output voltage ripple on the oscilloscope. Figure 4.
Typical Characteristic Curves www.ti.com 7 Typical Characteristic Curves Figure 5 through Figure 10 present typical performance curves for the UCC24610EVM-563. NO-LOAD POWER CONSUMPTION vs LINE VOLTAGE EFFICIENCY vs LOAD 0.85 500 0.80 450 400 0.75 85 VAC Input Power - mW 115 VAC h - Efficiency - % 265 VAC 0.70 0.65 230 VAC 0.60 350 300 150 0.50 100 265 VAC 85 VAC 50 0 0.40 0 1 2 3 4 80 5 100 120 140 160 180 200 220 240 260 280 VAC - Line Voltage - V Load - A Figure 5.
Typical Characteristic Curves www.ti.com GAIN/PHASE vs FREQUENCY GAIN/PHASE vs FREQUENCY 135 30 20 90 20 90 10 45 10 45 0 0 0 0 Phase -10 -45 Gain 180 135 Phase -10 -45 Gain -20 -90 -20 -90 -30 -135 -30 -135 -180 -40 -40 100 10000 1000 100000 Phase Margin - degrees Gain -dB 30 Gain -dB 40 Phase Margin - degrees 180 40 -180 100 1000 10000 100000 f - Frequency - Hz f - Frequency - Hz Figure 9. Gain Phase Bode Plot (Input voltage = 115-VAC, 5-A load.
Performance Data www.ti.com 8 Performance Data Figure 12. Primary-Side Waveforms (Input voltage = 115-VAC, no load, Green Mode operation.) Figure 13. Primary-Side Waveforms (Input voltage = 115-VAC, 1-A load, Amplitude Modulation Mode.) Figure 14. Primary-Side Waveforms (Input voltage = 115-VAC, 5-A load, Frequency Modulation Mode.) Figure 15. Primary and Secondary Currents (Current loops were added to EVM in the HV MOSFET drain and the trace from the transformer to the SR FET drain.
Performance Data 16 www.ti.com Figure 18. Close-Up View of VD and SR GATE (Input voltage = 115-VAC, 5-A load.) Figure 19. Secondary-Side Waveforms (Current loop added from transformer to SR FET gate. Input voltage = 115-VAC, 0-A load, Green Mode.) Figure 20. Secondary-Side Waveforms (Current loop added between transformer and SR FET gate. Low power mode. Input voltage = 115-VAC, 0.311-A load.) Figure 21. Secondary-Side Waveforms (Current loop added between transformer and SR FET gate.
Performance Data www.ti.com Figure 24. Output Voltage Ripple (Input voltage = 115-VAC, 5-A load.) SLUU434 – August 2010 Figure 25. Low Frequency Output Voltage Ripple (Input voltage = 115-VAC, 5-A load.
EVM Assembly Drawing and PCB Layout 9 www.ti.com EVM Assembly Drawing and PCB Layout Figure 26 through Figure 34 present EVM Assembly Drawing and PCB Layout drawings for the UCC24610EVM-563. Figure 26. Top Assembly Figure 27.
EVM Assembly Drawing and PCB Layout www.ti.com Figure 28. Top Paste Figure 29.
EVM Assembly Drawing and PCB Layout www.ti.com TEXAS I NSTRUMENTS Figure 30. Top Silk Figure 31.
EVM Assembly Drawing and PCB Layout www.ti.com Figure 32. Layer 2 Copper Figure 33.
EVM Assembly Drawing and PCB Layout www.ti.com Figure 34.
List of Materials www.ti.com 10 List of Materials Table 3. List of Materials for UCC24610EVM-563 COUNT 1 REF DES DESCRIPTION PART NUMBER MFR C1 Capacitor, ceramic, 330 pF, 630 V, C0G, NP0, ±5%, 1206 Std Std C2 Capacitor, ceramic disk, 1000 pF, 250 V, X1/Y1, ±20%, 0.394 inch x 0.315 inch ECK-ANA102MB Panasonic C3, C4 Capacitor, film, 0.33 µF, 275 VAC, X2, ±20%, 15 mm pitch, 0.690 inch x 0.
References www.ti.com Table 3. List of Materials for UCC24610EVM-563 (continued) COUNT DESCRIPTION PART NUMBER MFR R1 Resistor, chip, 64.9 kΩ, 1 W, ±1%, 2512 Std Std 1 R2 Resistor, chip, 33 Ω, 1 W, ±5%, 2512 Std Std 1 R3 Resistor, chip, 20 Ω, 1/4 W, ±1%, 1206 Std Std 3 R4, R6, R7 Resistor, chip, 2.05 MΩ, 1/8 W, ±1%, 0805 Std Std 1 R5 Resistor, chip, 10 Ω, 1/10 W, ±1%, 0603 Std Std 1 R8 Resistor, chip, 100 Ω, 1/10 W, ±1%, 0603 Std Std 1 R9 Resistor, chip, 6.
Evaluation Board/Kit Important Notice Texas Instruments (TI) provides the enclosed product(s) under the following conditions: This evaluation board/kit is intended for use for ENGINEERING DEVELOPMENT, DEMONSTRATION, OR EVALUATION PURPOSES ONLY and is not considered by TI to be a finished end-product fit for general consumer use. Persons handling the product(s) must have electronics training and observe good engineering practice standards.
IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete.
