BM1Z Series AC Voltage Zero Cross Detection ICs

ROHM's BM1Z series AC voltage zero-cross detection ICs eliminate the need for photocoupler and external components required in conventional applications. This makes it possible to drastically reduce the number of parts and realize compact and highly reliable power supply applications. In addition, it can greatly reduce standby power in comparison with an existing photocoupler control.

Along with reducing the number of parts, the design delivers a standby power consumption close to zero (0.01 W). In motor applications, it is possible to further decrease component count and standby power consumption by eliminating the motor input voltage detection circuit.

The BM1ZxxxFJ series supports the waveforms (pulse/edge) and circuit topologies (standard rectification/double rectification) utilized in conventional zero-cross detection circuits, allowing users to easily replace standard zero-cross detection circuits equipped with a photocoupler without requiring software changes.

The BM1ZxxxFJ series is compatible with input voltages up to 600 V and performs voltage division to output below the maximum rated voltage of the MCU and drives standard MCUs up to 5 V. A voltage clamp function that ensures the input voltage does not exceed 4.8 V is also included, protecting the MCU even when abnormal voltages are generated in high voltage drive applications such as air conditioners.