SM7525 [SMSC]

SM7525 is a primary side feedback controlling power chip used in off-line small power AC/DC switching power. It realizes high precision (less than ±5%) constant current output under universal input voltage. The circuit is no loop compensation and saves opto-coupler, L431, transformer auxiliary winding and other components to reduce the cost.The circuit integrates cycle by cycle peak current limiting, FB overvoltage protection, output open/short protection and soft-start, which optimize the reliability.