FD0257fR-G1
Features
Built-in high sensitivity Hall-effect sensor
H-Bridge MOS driver output
Output BTL soft-switching to reduce vibration and acoustic noise
PWM duty variable speed control
Tachometer signal output(FG)
Lock-shutdown protection & auto-restart function
Thermal shutdown protection
Available in TS826 package
For 5V BLDC motor / FAN systems
General Description
FD0257f is a LV single-phase full-wave BLDC motor driver IC with embedded Hall-effect sensor and rotation speed(FG) signal output. It integrates a H-bridge MOS driver, a high and precisely sensitive Hall-effect sensor and a digital control logic with an internal clock for rotor locked driver shutdown and auto re-start, tachometer(FG) output logic, and the BLDC motor’s PWM duty variable speed control function in the TS826 package, it makes the BLDC motors’ PCBs(printed circuit boards) design easy and fabrication of the ultra-small BLDC motors and FANs as simple as possible. 
For safety, Lock-shutdown function would turn the IC’s internal drivers off avoiding over-heat when the rotor is locked, and the IC will try to re-start the rotor’s torque after the time of these drivers’ shutdown. 
The IC contains the PWM direct input variable speed control and the tachometer(FG) signal output function, the external succeeding system could control the BLDC motor speed and readout the BLDC motor’s speed from the signal pin of FD0257f IC.
Thermal-shutdown protection(TSD) ensures the internal drivers of the IC are operating under a safe operating temperature range, and all the protection mechanisms mentioned above combine to provide a complete protecting scenario for the BLDC motor systems, avoid any possible damages and guarantee a correct and safe operation.
Application