SLVT249 May   2026

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1Test Prerequisites
    1. 1.1 Voltage and Current Requirements
    2. 1.2 Safety Warning
    3. 1.3 Dimensions
    4. 1.4 Test Setup
  8. 2Testing and Results
    1. 2.1 Efficiency Graphs
    2. 2.2 Efficiency Data
    3. 2.3 Thermal Images
      1. 2.3.1 PFC Stage
      2. 2.3.2 Thermal Image of System LLC Stage
      3. 2.3.3 Thermal Image of Backlight LLC Stage
    4. 2.4 PF Value
  9. 3Waveforms
    1. 3.1 Switching
      1. 3.1.1 PFC Switching waveform
      2. 3.1.2 System LLC Switching Waveform
      3. 3.1.3 Backlight Switching Waveform
    2. 3.2 Output Voltage Ripple
      1. 3.2.1 System LLC Output Ripple
      2. 3.2.2 Backlight LLC Output Ripple
    3. 3.3 Dynamic Response
      1. 3.3.1 Dynamic Response of the System LLC
      2. 3.3.2 Dynamic Response of the Backlight LLC
  10.   Trademarks

1.4 Test Setup

The block diagram of the flat screen TV power is shown in Figure 1-1. The diagram includes three parts: main board which is the interleave PFC stage, and two daughter boards, one board for the system power (Vout 1 and Vout 2), and the other board is for the backlight (Vout 3). The test procedure is:

  1. Make sure all connections. Set the standby load current on Vout 1 (<50mA)
  2. Applied input AC voltage on the main board. Vout 1 and Vout 2 should be ready when the AC voltage >80V. Vout 1 is 7.5 ~ 9V and Vout 2 is about 17 ~ 19V.
  3. Apply 5V on Power_On pin to enable the PFC and backlight power (Vout 3). Vout 1 and Vout 2 should be 12.5V and 25V. It is possible to load higher current on the system. Vout 3 is 18V.
  4. Apply external power source on Vout_Adj pin start from 0V. Adjust the voltage on the DC source and confirm the Vout 3 to be the voltage to be tested
PMP23488 Test SetupFigure 1-1 Test Setup