A hair removal device is a beauty instrument that uses technologies such as laser or radio frequency to remove excess hair. In a hair removal device, a Hall switch is used to detect and control the energy output of the laser or radio frequency. When the Hall switch detects that the energy output of the laser or radio frequency reaches a predetermined value, it will send a signal to control the instrument to stop working to protect the skin from excessive damage.

The application principle of the Hall switch of the hair removal device is that when the user brings the instrument close to the skin surface, the Hall element senses the change in the magnetic field, triggers the start of the instrument, and starts the hair removal operation. When the user moves the instrument away from the skin surface, the magnetic field change is sensed again and the instrument stops working. This automatic start-stop function makes the hair removal process more intelligent and safer. Users do not need to manually control the switch, reducing the complexity of the operation and possible misoperation.

Due to the convenience of carrying, all handheld laser hair removal devices require small size and battery power supply, so the Hall switch requires low power consumption, high sensitivity, good consistency, and convenient magnet installation. The Hall switch detects non-polar magnets and can be triggered only by magnets.

HS481 is a polarity-free Hall switch based on mixed-signal CMOS technology. This IC uses advanced chopper stabilization technology to provide accurate and stable magnetic switch points.

In terms of circuit design, HS481 provides an embedded controlled clock mechanism to provide clock sources for Hall devices and analog signal processing circuits. At the same time, this controlled clock mechanism can send control signals to make the circuits with large current consumption periodically enter "sleep" mode;

Also through this mechanism, the chip is periodically "woken up" and detects the magnitude of the magnetic field strength passing through the Hall device according to the predetermined magnetic field strength threshold.

If the magnetic flux density is higher than the "operating point" threshold or lower than the "release point" threshold, the open-drain output transistor is driven and latched into the corresponding state. During the "sleep" cycle, the output transistor is locked in its previous state.

In battery-powered applications, this design provides the best support for extending the working life. The output transistor of HS481 is locked in the on state when there is a certain strong south or north magnetic field facing the package marking side, and is locked in the off state when there is no magnetic field.