STPA001 MOSFET Quad Bridge Power Amplifiers STMicroelectronics STPA001 MOSFET Quad Bridge Power Amplifiers have breakthrough MOSFET technology and are designed for high-power car radio. The STPA001 feature a fully complementary P-Channel/N-Channel output structure. This structure allows a rail-to-rail output voltage swing which, combined with high output current and minimized saturation losses, sets new power references in the car-radio field.