Charger MOSFETs

Four PowerPAK 1212-8 MOSFET devices designed for battery charger switching and protection applications have been announced by Siliconix.

The lead-less 1212-8-packaged devices save space and provide good thermal performance in low-height-profile packages with small footprint areas in mobile and cordless phones, pagers, PDAs and other portable devices and include the first combination power MOSFET and Schottky diode devices in the PowerPAK package.

Like all PowerPAK 1212-8 devices, the Si7900EDN, Si7901EDN, Si7703EDN, and Si7705DN each provides a low height profile of 1.07 mm, with a footprint area of 10.56 mm2. The package provides increased maximum current handling from 6.5 to 9 A. Power dissipation nearly doubles compared to any other power MOSFET device with a TSSOP-8-size footprint or smaller, increasing from 1.67 to 3.2 W.

The common-drain dual n-channel Si7900EDN provides single- or dual-cell Lithium ion battery pack protection, with a low on-resistance of 26 mohm at a 4.5 V gate drive, plus 3000-V ESD protection against electrostatic damage caused by handling and use of plug-in accessories. The first dual p-channel PowerPAK 1212-8 packaged device, the Si7901EDN, is a bidirectional battery switch for portable electronic systems. It features a low on-resistance of 48 mohm at a -4.5 V gate drive with ESD protection of 4500 V.

The Si7703EDN and Si7705DN are single p-channel PowerPAK MOSFETs - the first to feature an integrated Schottky diode in a 1212-8 package - designed for battery charger switching in portable devices.

Each has an on-resistance of 48 mohm at a -4.5 V gate drive. The Schottky diode integrated into these two devices has a forward voltage of 0.48 at 0.5 A with reverse voltage of 20 and an average forward current of 1.0 A.