The number of electric modules in vehicles is increasing rapidly. Motorists’ insatiable demand for safety, comfort, economy, a clean environment,
and overall quality of driving are the main drivers behind this explosive growth. In its Toulouse, France, facility, Freescale Semiconductor develops
some integrated solutions to replace electromechanical relays, fuses, and discrete components in automotive power management applications.This family of products, named eXtreme Switch, is designed for harsh
environments, fulfilling all the automotive requirements. The first devices of this family are dedicated to low-frequency applications (300 Hz)
such as lighting. They allow driving up to 50 A dc with on-resistance (RDSON) of 2 mV maximum at room temperature [1].
Many automotive applications, such as fan motor controls or fuel pumps, require pulse width modulation (PWM) higher than 20 kHz to
adjust motor speed. For these PWM applications, conventional approaches are designed with discrete components that are not optimized in terms
of print circuit board (PCB) size, protections, and diagnostics [2]. This article presents a fan control unit requiring 30 A motor currents up
to 20 kHz PWM. The smart integrated circuit (IC) used here includes a selfprotected high-side switch with 4 mV RDSON, all digital control from a microcontroller,
and extended diagnostics. High-current switching at high