Related Manuals for Texas Instruments UCC28740EVM-525
Summary of Contents for Texas Instruments UCC28740EVM-525
- Page 1 User Guide SLUUAL8 – July 2013 Using the UCC28740EVM-525 10 W Constant- Voltage, Constant-Current Charger Adaptor Module User’s Guide Literature Number: SLUUAL8 July, 2013...
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Page 2: Table Of Contents
UCC28740EVM-525 Line Regulation ................15 Figure 7. UCC28740EVM-525 No-Load Power Consumption ............15 Figure 8. UCC28740EVM-525 Output Voltage as a Function of Load Current ......16 Figure 9. UCC28740EVM-525 Control Law Showing Switching Frequency as a Function of Load Current ........................17 ... - Page 3 Figure 14. Switching Waveform ......................22 Figure 15. EMI Dithering Waveform ....................23 Figure 16. UCC28740EVM-525 Top Layer Assembly Drawing (Top view) ........24 Figure 17. UCC28740EVM-525 Bottom Layer Assembly Drawing (Bottom view) ......25 Figure 18. UCC28740EVM-525 Top Copper (Top View) ..............26 ...
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Page 4: Introduction
SLUUAL8 1 Introduction The UCC28740EVM-525 evaluation module is a 10 Watt off-line discontinuous mode (DCM) flyback converter that provides constant-voltage (CV) and constant-current (CC) output regulation by using an optical coupler for tight voltage regulation and improved the transient response to large load steps and primary side control for accurate constant current regulation. -
Page 5: Features
SLUUAL8 2.2 Features The UCC28740EVM-525 features include: AC Input Range 85 V to 265 V DC Output of 5 V, 2.1 A No-Load Power Consumption less than 20 mW Opto-Coupled Feedback for Constant Voltage Regulation and Fast Dynamic Response ... -
Page 6: Electrical Performance Specifications
SLUUAL8 3 Electrical Performance Specifications Table 1. UCC28740EVM-525 EVM-001 Electrical Performance Specifications PARAMETER TEST CONDITIONS UNITS Input Characteristics Voltage range, V 115/230 Maximum input current 0.265 INmin OUTmax Line frequency 60/50 No-load power ≤ V ≤ V , I = 0A INmin INmax consumption... -
Page 7: Schematic
SLUUAL8 4 Schematic Figure 1. UCC28740EVM-525 Schematic... -
Page 8: Test Setup
Figure 3 shows the recommended test equipment set up to evaluate the UCC28740EVM-525 with a load. Warning High voltages that may cause injury exist on this evaluation module (EVM). -
Page 9: Recommended Test Setup
SLUUAL8 5.2 Recommended Test Setup Figure 2. UCC28740EVM-525 Recommended Test Set Up For No-Load Operation... -
Page 10: List Of Test Points
SLUUAL8 Figure 3. UCC28740EVM-525 Recommended Test Set Up With Load 5.3 List of Test Points Table 2. Test Point Functional Description TEST POINT NAME DESCRIPTION PGND Primary side power ground +LOOP Loop injection point, EVM output -LOOP Loop injection point... -
Page 11: Applying Power To The Evm
SLUUAL8 TEST POINT NAME DESCRIPTION SGND Secondary side ground +VOUT Positive output terminal of the EVM to the load -VOUT Return connection of the EVM output to the load 5.4 Applying Power to the EVM 1. Set up the EVM as shown in Figure 2 if testing at no-load, or Figure 3 if testing with a load. 2. -
Page 12: Output Voltage Ripple
SLUUAL8 Observe that if the constant resistance level of the electronic load is decreased lower than the full load value, the EVM will maintain constant current regulation within 5% of the programed value until the output voltge drops below 2 V. The EVM will automatically restart once the constant resistance load is increased. -
Page 13: Performance Data And Typical Characteristic Curves
SLUUAL8 6 Performance Data and Typical Characteristic Curves Figure 4 through 11 present typical performance curves for UCC28740EVM-525. 6.1 Efficiency AVERAGE EFFICIENCY 0.820 0.815 0.810 0.805 0.800 0.795 0.790 0.785 0.780 0.775 0.770 0.765 0.760 0.755 0.750 INPUT VOLTAGE (V Figure 4. UCC28740EVM-525 Average Efficiency The average efficiency at 115 VAC, 60 Hz nominal input and 230 VAC, 50 Hz nominal input exceeds the 0.80 design goal. -
Page 14: Load Regulation
SLUUAL8 6.2 Load Regulation LOAD REGULATION ‐0.1 ‐0.2 ‐0.3 ‐0.4 ‐0.5 INPUT VOLTAGE (V Figure 5. UCC28740EVM-525 Load Regulation Figure 5 shows the actual measured load regulation exceeded the 3% design goal. -
Page 15: Line Regulation
6.3 Line Regulation LINE REGULATION ‐0.1 ‐0.2 ‐0.3 ‐0.4 ‐0.5 PERCENT OF FULL LOAD (%) Figure 6. UCC28740EVM-525 Line Regulation Figure 6 shows the actual measured line regulation exceeded the 3% design goal. 6.4 No-Load Power Consumption NO‐LOAD POWER CONSUMPTION INPUT VOLTAGE (V Figure 7. UCC28740EVM-525 No-Load Power Consumption... -
Page 16: Output Voltage Vs Output Current
265 VAC, 50 Hz Figure 8. UCC28740EVM-525 Output Voltage as a Function of Load Current In Figure 8, the converter is in constant-voltage operating mode from 0 A load up to approximately 2.2 A. Once reaching this output over-current threshold, the converter transitions into constant- current mode where the load current remains constant until the output voltge falls below 2 V, at which point the converter shuts down. -
Page 17: Control Law
325VDC 375VDC Figure 9. UCC28740EVM-525 Control Law Showing Switching Frequency as a Function of Load Current As the load increases, the UCC28740 will transition from a frequency modulation mode at light load, where the peak primary current is fixed at ¼ of its maximum programmed value, into a 32 kHz fixed frequency, peak current amplitude modulation mode. -
Page 18: Bode Plot
GAIN (dB) PHASE (degrees) Figure 10. UCC28740EVM-525 Loop Response Gain and Phase The gain, phase plot was measured with an AP Instruments Inc. Model 200 analog network analyzer. The loop result was obtained by inserting a 200mV AC signal across TP2 and TP3. The crossover frequency, with a 115 V , 60 Hz input and load current of 2 A, measured 1.38 kHz with a... -
Page 19: Transient Response
SLUUAL8 6.8 Transient Response Figure 11. UCC28740EVM-525 Load Transient The transient response shown in Figure 11 was taken with a 115 VAC, 60 Hz input voltage and a load transition from 0 A to full load. Channel 1 is the load current on a scale of 1 A per division, channel 4 is the otutput voltage on a scale of 1 V per division. -
Page 20: Output Ripple
SLUUAL8 6.9 Output Ripple Figure 12. Output Ripple Figure 12 shows the output voltage ripple, measured using tip and barrel across TP5 and TP6 on the EVM. The measurement was taken at full load with an input voltage of 85 VAC, 60 Hz and the waveform is AC coupled. -
Page 21: Turn On Waveform
SLUUAL8 6.10 Turn On Waveform Figure 13. Output voltage Turn On Waveform Figure 13 shows the output voltage at turn on under full load conditions with an input voltage of 115 , 60 Hz. The maximum voltage at the output was measured to be 5.12 V... -
Page 22: Switching Waveform
SLUUAL8 6.11 Switching Waveform Figure 14. Switching Waveform The typical switching waveform can be seen inFigure 14. Channel 1 shows the VS pin at 2 V per division and channel 2 shows the MOSFET drain to source voltage at 100 V per division. The scan was taken at 1.8 A load, 115 V , 60 Hz input voltage. -
Page 23: Emi Dithering Waveform
EMI compliance. 7 EVM Assembly Drawing and PCB layout The following figures (Figure 16 through Figure 19) show the design of the UCC28740EVM-525 printed circuit board. The final dimensions of the single copper layer circuit measure 50.93 mm by... -
Page 24: Figure 16. Ucc28740Evm-525 Top Layer Assembly Drawing (Top View)
SLUUAL8 Figure 16. UCC28740EVM-525 Top Layer Assembly Drawing (Top view) -
Page 25: Figure 17. Ucc28740Evm-525 Bottom Layer Assembly Drawing (Bottom View)
SLUUAL8 Figure 17. UCC28740EVM-525 Bottom Layer Assembly Drawing (Bottom view) -
Page 26: Figure 18. Ucc28740Evm-525 Top Copper (Top View)
SLUUAL8 Figure 18. UCC28740EVM-525 Top Copper (Top View) -
Page 27: Figure 19. Ucc28740Evm-525 Bottom Copper (Bottom View)
SLUUAL8 Figure 19. UCC28740EVM-525 Bottom Copper (Bottom View) -
Page 28: Bill Of Materials
SLUUAL8 8 Bill of Materials Table 3. The EVM components list according to the schematic shown in Figure 1 REFDES DESCRIPTION PART NUMBER 2 C1, C2 CAP, CERM, 2.2 µF, 50 V, X7R, ±10%, 0805 Taiyo Yuden UMK212BB7225KG‐T 2 C3, C4 CAP, ALUM, 6.8 µF, 400 V, ±20%, 110 mA, Radial United Chemi‐Con EKXG401ELL6R8MJ16S 1 C5 CAP, CERM, 0.047 µF, 25 V, X7R, ±5%, 0603 06033C473JAT2A 1 C6 CAP, CERM, 100 pF, 250 V, X1Y2, ±10%, Radial, Disc TDK Corporation ... - Page 29 SLUUAL8 REFDES DESCRIPTION PART NUMBER 1 R7 RES, 196 kΩ, ±1%, 0.1 W, 0603 Yageo America RC0603FR‐07196KL 1 R9 RES, 1.27 kΩ, ±1%, 0.1 W, 0603 Vishay‐Dale CRCW06031K27FKEA 2 R10, R11 RES, 1.87 Ω, ±1%, 0.125 W, 0805 Vishay‐Dale CRCW08051R87FKEA 1 R12 RES, 49.9 Ω, ±1%, 0.25 W, 1206 Vishay‐Dale CRCW120649R9FKEA 0 R13 RES, 820 Ω, ±1%, 0.1 W, 0603 Yageo America RC0603FR‐07820RL 0 R14 RES, 2.00 kΩ, ±1%, 0.1 W, 0603 Vishay‐Dale CRCW06032K00FKEA 1 R15 RES, 1.50 kΩ, ±1%, 0.25 W, TH Vishay‐Dale CMF501K5000FHEB 1 ...
- Page 30 EVALUATION BOARD/KIT/MODULE (EVM) WARNINGS, RESTRICTIONS AND DISCLAIMER For Feasibility Evaluation Only, in Laboratory/Development Environments. The EVM is not a complete product. It is intended solely for use for preliminary feasibility evaluation in laboratory / development environments by technically qualified electronics experts who are familiar with the dangers and application risks associated with handling electrical / mechanical components, systems and subsystems.
- Page 31 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.
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