October 11, 2011
Allegro MicroSystems, Inc. adds a new low side MOSFET pre-driver IC to complement their existing automotive pre-driver portfolio. Allegro’s A3944 is a programmable 6 channel low side MOSFET control IC, with a 50 V rating on drain feedback inputs, making this device suitable for use in automotive diesel applications. Due to the extensive diagnostics and wide operating voltage range this new device is targeted at the automotive market; however, it may also be used in consumer and industrial applications.
Each channel is controllable by a combination of parallel and serial inputs and provides sufficient gate drive current to allow PWM control up to 10 kHz, depending on the MOSFET gate charge. Each channel provides independent fault diagnostics for short to ground and open load when in the “off state,” and short to battery when in the “on state.” A short to battery can disable the output until reset or for a programmable retry time. Each channel provides independently programmable fault thresholds and blanking times. In addition to channel state control, channel fault masking, fault thresholds and fault timers are programmed through the SPI compatible serial interface. The serial interface also provides read back of the fault status for each channel. Digital inputs and outputs are compatible with 3.3 V and 5 V supplies.
The A3944 is available in a 28-lead TSSOP (LP) package with exposed pad for enhanced thermal dissipation and is lead (PB) free with 100% matte tin plated lead frames.