Diodes Incorporated introduced the APR3415 and APR34330. These synchronous rectifiers address the need for higher integration and efficiency in portable chargers by combining a driver circuit with an internal MOSFET to provide cost-effective rectification with reduced power dissipation and fewer external components. Target applications include adapters/chargers for cellular and cordless phones, ADSL modems, MP3 players, and similar portable consumer products and home appliances.
The APR3415 and APR34330 are synchronous rectification switchers for 5 V output-voltage applications operating in discontinuous conduction mode. Synchronous rectification can reduce secondary-side power dissipation, while the devices’ ability to sense the MOSFET drain-to-source voltage enables an optimal drive signal using fewer external components. The internal N-channel MOSFET has been optimized for low gate charge, low RDS(ON), fast switching speed and reverse recovery, which helps these devices provide a fast response to secondary-side voltage and can also improve the transient performance of a primary-side control system.
The APR3415 is aimed at designs requiring output currents up to 2 A and is supplied in a standard SO-8 package. The APR34330 is intended for output currents up to 1.5 A and is offered in an SO-8EP exposed pad package. Both devices feature over-voltage protection (OVP) and VCC under-voltage lock out, which is not typically available on competitive devices. This not only aids system safety and reliability, but also extends the devices’ use in additional application areas, such as standby and auxiliary power supplies.
