IXYS and Clare have announced the release of new low voltage Power MOSFETs in small SOIC packages with voltage rating of 30V and below 1V of threshold voltage. These devices are optimized for low gate voltage turn on, for synchronous rectification, switching and power control for battery powered portable equipment.
A single MOSFET in an SOIC package is the CPC3801N, the dual MOSFETs in one SOIC package, the CPC3851N, with current ratings of 1 ampere and 80 milliohms of on resistance.
These power MOSFETs are ideal for solar chargers, as the isolation and synchronous rectifiers, between the solar cells and the battery in a solar battery charger application.
These MOSFETs are designed to be driven by the photovoltaic (PV) gate driver ICs from Clare, like the CPC 1822/24 and the CPC 1831/2 that are solar powered to turn these FETS on under light.
A full PCB based reference design (EVXOBA-12XI) for an "AA battery solar charger" is available for sale at IXYS' Colorado website that includes the IXYS solar cells, "IXOLARTM", the PV gate driver and the FET as the synchronous rectifier switch.
Targeted applications are low voltage DC to DC converters synchronous rectification, where these MOSFET can replace rectifier diodes in the output rectification circuits, thereby reducing conduction losses.
The ability of these MOSFETs to be switched at higher than 200Khz, enable the design of smaller and more efficient power supplies.
Replacing a diode for rectification (which drops typically 400 millivolts to 600 millivolts of forward voltage drop) with these new FETs reduces the voltage drop down to 20 millivolts for a 0.25A application. A 20 times reduction of power losses reduction in rectification.
