Looking to interface high voltage or noisy signals with a microcontroller, Raspberry Pi, or Arduino? Look no further!

This 8 channel input optoisolator board accepts nominal voltages of 5­-24V (max of 40V) on the input side, while generating clean and regulated 3.3­-5V signals on the output side. Feeding an input a LOW/grounded state will produce a LOW/grounded state on the output and vice versa.

New Revision with mounting holes!

The latest revision (1.1b, shown below) now has screw holes for easy mounting.

With large screw terminals, clearly visible LEDs indicating state, and optional 2.54mm headers, this board is a breeze to work with.

While retrofitting/updating CNC machines in our shop with Arduinos and Raspberry Pis, we realized very few options existed for cleanly connecting 24­V signals to our favorite low cost development boards. Rather than hacking together several smaller boards or modifying less than ideal existing solutions, we developed this robust and simple optoisolator board ourselves.

Note that this board is able to adapt to the specific voltage ranges required of your use case. The HVIN pin is used to select the voltage of input signals, while the LVIN pin is used to select the voltage of the output signals.

There are two sides of the board

• High Voltage (5­-24VDC) inputs which will be referred to as "HV"
• Low Voltage (3.3­-5VDC) outputs which will be referred to as "LV"

Directions

1. Attach your HV power source to the HVIN pin of HV INPUT side
2. Attach your HV ground to the HVGND pin of HV INPUT side
3. Attach your LV power source to the LVIN pin of LV OUTPUT side
4. Attach your LV ground to the LVGND pin of the LV OUTPUT side
5. Connect any HV output signals to pins 1 through 8 of the HV INPUT side
6. Connect any microcontroller input or LV input to pins 1 through 8 of the LV OUTPUT side

Additional Notes

• HV signals only act as an inputs to the board
• LV signals only act as outputs from the board
• A HIGH state on the input corresponds to a HIGH state on the output and vice versa
• I/O is pulled HIGH when not actively pulled to GND
• If your application does not pull the signal low (but rather disconnects), you can safely add a 1K resistor between LVGND and the high voltage input on the left side of the board. This will force the signal to GND when nothing is connected

Absolute Max Ratings

• HVIN Supply Voltage = 5­-40VDC
• LVIN Supply Voltage = 3­6VDC
• Signal Frequency = 5 KHz

Verified Compatible With

• Raspberry Pi 1/2/3
• Arduino
• Beaglebone Black/Green
• ODroid C1/C1+/C2

DATASHEET

SCHEMATIC

DIMENSIONS / MOUNTING (Note that units are imperial/US)

Board developed and produced by Noop Labs LLC.

Support available via support@nooplabs.com.