AH280 is an integrated Hall sensor that has two complementary outputs for driving motor coils, auto-locked shutdown and auto-restart functions. Functional block diagram includes a temperature-compensated bandgap regulator, an on-chip Hall voltage generator, a comparator, a Schmitt trigger and two current output drivers. The regulator can provide wide operational voltage range. The Hall voltage generator is to amplify the Hall voltage due to Hall effect. A Schmitt trigger is to provide switching Hysteresis for noise rejection. To avoid coil burning, rotor-lock detection circuit will shutdown the output driver if detect rotor-lock, and automatically restart.
The AH280 is a smart fan driver designed to drive two complementary outputs for motor coils. It includes built-in protection features such as a Zener diode for the output driver and a diode for power reverse connection. The device incorporates an on-chip Hall plate, a regulator with temperature-compensated band-gap, and a Schmitt trigger for noise rejection.
Key operational features include rotor-lock detection which shuts down the output if the motor stalls, and an automatic restart circuit that resumes operation once the lock is cleared. The auto-restart time is adjustable via an external capacitor (CT). The device supports operating voltages from 3.5V to 20V and offers packages including SIP-5L, SOP-8L, and SOP-8L EP.
| Operating Voltage | 3.5~20 V |
|---|---|
| Max Output Current | 500 mA |
| Operating Temperature Range | -20~85 °C |
| Storage Temperature Range | -55~150 °C |
| Comparator Voltage (Vcp) | 1.0 V |
The CT pin is used for a timing capacitor to adjust the automatic restart time after a motor lock condition is cleared.
The device detects a motor lock when the Hall signal stops switching, causing it to shut down the output driver.