Specifications
- The relay closes on HIGH
- Galvanically isolates the switched circuit
- You can stack another module on top of it
- Relay coil on 5 V, a transistor switches it from a 3.3 V pin
- Current ≈ 70–90 mA with the relay on, almost nothing when off (estimate based on common 5 V relays)
- Does not use the I2C bus
- Uses: isolating circuits, controlling devices
Pins
A jumper on the module switches the pin to IO6, IO7 or IO8, so you can stack several identical modules.
| Pin | Function |
|---|---|
| IO5 | Relay control (RELAY) |
Wiring diagram
Example code
Try the example Hallway light right in your browser in Eduingo AI Lab. Just like the light switch in a block of flats: press any button, the relay turns the light on and switches it off by itself after 5 seconds. A relay is a switch that can turn on even a big lamp. Try making button BTN4 keep the light on for longer.