Texas Instruments UCC28740EVM-525, User Manual

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SLUUAL8
Using the UCC28740EVM-525 10 W Constant-Voltage, Constant-Current Charger Adapter Module
PSS- High Performance Isolated
Contents
1 Introduction ..................................................................................................................................... 4
2 Description ...................................................................................................................................... 4
2.1 Typical Applications .................................................................................................................. 4
2.2 Features .................................................................................................................................... 5
3 Electrical Performance Specifications ......................................................................................... 6
4 Schematic ........................................................................................................................................ 7
5 Test Setup ....................................................................................................................................... 8
5.1 Test Equipment ......................................................................................................................... 8
5.2 Recommended Test Setup ....................................................................................................... 9
5.3 List of Test Points ................................................................................................................... 10
5.4 Applying Power to the EVM .................................................................................................... 11
5.5 No-Load Power Consumption ................................................................................................. 11
5.6 Line/Load Regulation and Efficiency Measurement Procedure .............................................. 11
5.7 Output Voltage Ripple ............................................................................................................. 12
5.8 Equipment Shutdown .............................................................................................................. 12
6 Performance Data and Typical Characteristic Curves .............................................................. 13
6.1 Efficiency ................................................................................................................................. 13
6.2 Load Regulation ...................................................................................................................... 14
6.3 Line Regulation ....................................................................................................................... 15
6.4 No-Load Power Consumption ................................................................................................. 15
6.5 Output Voltage vs Output Current ........................................................................................... 16
6.6 Control Law ............................................................................................................................. 17
6.7 Bode Plot ................................................................................................................................ 18
6.8 Transient Response ................................................................................................................ 19
6.9 Output Ripple .......................................................................................................................... 20
6.10 Turn On Waveform ................................................................................................................. 21
6.11 Switching Waveform ............................................................................................................... 22
6.12 EMI Dithering Waveform ......................................................................................................... 23
7 EVM Assembly Drawing and PCB layout ................................................................................... 23
8 Bill of Materials ............................................................................................................................. 28
Figures
Figure 1. UCC28740EVM-525 Schematic ......................................................................................... 7
Figure 2. UCC28740EVM-525 Recommended Test Set Up For No-Load Operation .................... 9
Figure 3. UCC28740EVM-525 Recommended Test Set Up With Load ........................................ 10
Figure 4. UCC28740EVM-525 Average Efficiency ......................................................................... 13
Figure 5. UCC28740EVM-525 Load Regulation ............................................................................. 14
Figure 6. 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
Figure 10. UCC28740EVM-525 Loop Response Gain and Phase .................................................. 18