TZT KY-019 5V One 1 Channel Relay Module Board Shield For PIC AVR DSP ARM for arduino Relay

2, can be used as microcontroller development board module can be used as home appliance control

3,5 V-12V to TTL control signal

4, the control signal DC or AC, 220V AC load can be controlled.

5, there is a normally open and one normally closed contact

6, a power indicator light

7, a control indicator, pull off, disconnect does not shine

8, transistor drive to increase the relay coil control pins high impedance.

9, the control pin has a pull-down circuit to prevent malfunction relay vacant