Dc Fan Pwm Control
Mosfet Driver With Pwm Fans
Designed for pulse-width-modulated (PWM) control of DCmotors, the A4955 is capable of 50 V operation and providesgate drive for an all N-channel external MOSFET bridge.Input terminals are provided for use in controlling the speed anddirection of a DC motor with externally applied PWM controlsignals. Internal synchronous rectification control circuitry isprovided to lower power dissipation during PWM operation.Internal circuit protection includes VDS protection, thermalshutdown with hysteresis, undervoltage monitoring of VBB,and crossover-current protection.The A4955 is supplied in a low-profile 4×4 mm, 20-contactQFN package (suffix “ES”) and a 20-lead eTSSOP (suffix“LP”), both with exposed thermal pad.