Diodes Incorporated's new AH37xx series of high-voltage Hall-effect latch ICs provide a variety of operating magnetic thresholds to meet motor control, rotational position, and speed sensing requirements in a wide range of applications, such as controlling brushless DC (BLDC) commutation) washing machines , Motors in dishwashers, refrigerators and freezers, air conditioners, food processors, power tools and cooling fans; speed measurement of motors, pumps and flow meters; and non-contact position sensing / indexing in printers, scanners and shutters.
The AH37xx series covers industrial and consumer applications, and is suitable for operating voltages from 3V to 28V. It also integrates reverse blocking diodes, Zener clamps on input / output pins, and output current limit to provide protection against transient and Overload protection. The extended temperature specifications range from -40oC to + 125oC and a low temperature coefficient ensures reliable operation at the switching threshold, while the 6kV ESD capability increases robustness and eases operation during manufacturing.
System design flexibility is achieved through different magnetic operation and release thresholds (BOP and BRP) in the series: AH3772 / 4 and AH3781 / 2 have BOP and BRP of + 25G / + 40G and -25G / -40G, providing High sensitivity. The medium sensitivity AH3775 / 6 parts are rated at + 70G / + 110G and -70G / -110G, while the AH3777 has the lowest sensitivity with + 140G and -140G specifications. Between the open-drain AH377x series and AH378x parts, designers can also choose the output configuration, which has internal pull-up resistors to reduce the number of BOMs and save board space.
The AH37xx Hall-effect latch IC has excellent performance, with a fast power-up time of 10 μs and a fast response time of 3.75 μs, thereby reducing delay and commutation errors. A chopper-stabilized architecture with internal bandgap regulator ensures temperature stability, minimizes switching point drift and enhances resistance to stress. The device also has good radio frequency immunity, further improving the reliability of the overall operation.
