USB relay board is one kind of very popular switch module. You can use it control any devices on or off. This is a DC 5V controlled 1 channel relay module. It can be controlled directly by a wide range of microcontrollers such as Arduino, AVR, PIC, ARM and so on. It has high level trigger. Trigger current need not be less than 5mA, part of the MCS51 MCU IO output capability is weak, require pull-up resistor or increase the drive capability of the circuit.
- 1-Channel Relay interface board, - Each one needs 15-20mA Driver Current - Equipped with high-current relay : DC30V 10A AC250V 10A - Standard interface that can be controlled directly by microcontroller