Chip Replaces Transformers In Low Wattage Switchers

Integrating on-chip a 700V power MOSFET and PWM control, high-voltage start-up, current limiting, and thermal shutdown circuitry, the LNK501 LinkSwitch is designed to replace less efficient linear transformers in ac/dc adapters and battery chargers rated at 3W and below. Together with as few as 14 components, the high voltage ac/dc converter IC is said to enable the design of fault-protected, universal, 85 to 265 Vac input switching power supplies having a constant voltage, constant current (CV/CC) output and that meet worldwide energy efficiency standards. The power conversion IC does away with the need for current sense resistors, consumes