AH288

Features AH288 HIGH VOLTAGE HALL-EFFECT SMART FAN MOTOR CONTROLLER General Description On chip Hall sensor Rotor-locked shutdown Automatically restart Frequency generator (FG) output Built-in Zener protection for output driver Operating voltage: 3.8V~28V Output current: IO(AVE) = 400mA Lead Free Package: SOT89-5L (Note 1) SOT89-5L: Available in “Green” Molding Compound (No Br, Sb) Lead Free Finish/RoHS Compliant (Note 2) AH288 is a monolithic fan motor controller with Hall sensor’s capability. It contains two complementary open-drain transistors as motor coil drivers, automatic lock current shutdown, and recovery protections. Additional, frequency generator (FG) output is for speed detection relatively. Rotor-lock shutdown detection circuit turns off the output driver when the rotor is blocked to avoid coil overheat. Then, the automatic recovery circuit will restart the motor. These protected actions are repeated and periodic during the blocked period. Until the blocking is removed, the motor recovers and runs normally. Typical Application Circuit Vdd (24V) D2 D1 Rpu FG D3 C1 * Rpu : typical 10 Kohm 54 288 123 GND Coil2 Coil1 48V 48V Note: The optional Capacitor C1 and Diode D3 are for power stabilization. C1 is recommended to be E-Cap., luF/25V; D3 is recommended to be Zener Diode, VZ =27V. Which C1and D3 value need to be fine tuned to optimize design for different coils and power suppliers . 24V DC Brush-less Fan with FG output function AH288...