Skyworth 168P-L3L027-K0 SMPS board schematic – TEA1733T-N2, OZ568GN

General description of power supply
This power supply is suitable for 32" LED TV. For 32" LED panel, supplies 4 channels, each channel nominal current value is 90mA; for 32” main board, only supplies +12V power, rated current value +12V/2.5A.
The main part of the circuit：TEA1733T
The main chip of power supply is the TEA1733T which is produced by NXP corporation.The operating mode is CCM (continuous conduction mode), and the operating frequency is 65KHz.

LED driver chip
The chip using OZ568GN, is a highly integrated and high performance LED driver that optimized for LCD backlight application.
Circuit diagram [Schematic] and PWB top and bottom view

Fault Analysis

1. No +12V output voltage
 If there is no +12V output voltage , we should focus on checking the main chip (U6) and judge whether the IC is operating . Monitor its VIN pin and check voltage is normal or abnormal . If it is normal , firstly , check the main chip peripheral circuit . Secondly, check main chip and judge it has broken or not.
2. +12V output is abnormal Check the +12V feedback loop , and the reference voltage of the U3 is normal or not