When the 3.3V digital output mode of your VINT port is not enough, this output module adds four PWM-enabled solid state relay outputs to your system. Because it uses relay outputs, you can control more powerful devices that require up to 30V and 8A. LED strips, DC motors, power relays, fans and other small circuits are just a few examples of what can be controlled with this module.
Each solid state relay switches an external circuit to ground when enabled. This action allows completion of the circuit in order to power a load. The power to the load is supplied externally and should be connected in series with the load and the relay output. Alternatively, you could use a pull-up resistor on the input of your load and then switch the input to ground when you want it to turn off. Each channel has a ground terminal beside it to make wiring a snap, and each one leads to a common ground.
In addition to switching at microsecond speeds, each relay output is also capable of pulse-width modulation; rather than simply switching on or off, you can select a percentage duty cycle to limit the power being supplied to a specific level. This allows you to control devices like a dimmer would, which is an important feature for LEDs, fans, and motors. Check the datasheet for your device to ensure that it is designed to be used with PWM (some devices such as incandescent or CF bulbs are not designed for dimming).
Isolated for Stability
The VINT port on this board is electrically isolated from the rest of the board, improving stability by eliminating ground loops.
|Current Consumption Min||3.5 mA|
|Current Consumption Max||4 mA|
|Load Voltage Max (DC)||30 V DC|
|Load Current Max (DC)||8 A|
|Switching Power Max (Real)||* 240 W|
|Number of Relays||4|
|Contact Resistance Max||35 mΩ|
|Turn-off Time Max||100 ns|
|Switch Type||SPST Normally Open MOSFET|
|Turn-on Time Max||100 ns|
|PWM Resolution||0.1 %|
|PWM Frequency Max||16 kHz|
|Recommended Wire Size||16 – 26 AWG|
|Operating Temperature Min||-40 °C|
|Operating Temperature Max||85 °C|
* Note: At switching powers powers higher than 50W, external cooling may be required. For high power applications, a hockey-puck style SSR may be more appropriate. See the “Other Relays” tab for more details.