4 Channel Opto Isolation Module High and Low Expansion Board

This board is helpful for connecting digital systems (like a 5V microcontroller) to a high-voltage or noisy system. This board electrically isolates a controller from the high-power system by use of an opto-isolator IC. This IC has four LEDs and four photodiodes built-in. This allows the low-voltage side to control a high voltage side.

We often use this board to allow a microcontroller control servos or other motors that use a higher voltage than the TTL logic on the (3.3V or 5V) micro, and may cause electromagnetic interferance with our system as the motors turn on and off. This board will isolate the systems, creating a type of electrical noise barrier between devices.

This breakout board uses the TLP281 optoisolator and discrete transistors to correct the logic. Comes with four channels. Great for use in noisy circuits where signal lines require electrical isolation.

A normal LED opto-isolator will invert the logic of a signal. We threw some transistors on this compact board to correct the inversion. What you put into the IN pins, will be replicated on the the OUT pins, but at the higher voltage (HV).

PCB Size: 25mm x 26mm

Function:

1. Use low level control high. For example, microcontroller use 3V or 5V voltage to control  9V or 12v voltage.
2. HVCC not exceed the maximum 24V. Output port OUT1 / OUT2 / OUT3 / OUT4 maximum output current is equal to HVCC / 5.1K, the maximum absorption current 500mA.
3. This module uses the Toshiba TLP281 chip.

Input / Output Description:

• Inputs: IN1 / IN2 / IN3 / IN4, connected microcontroller or Arduino IO port, GND and microcontroller Arduino development board or GND connection. IN1 / IN2 / IN3 / IN4 control OUT1 / OUT2 / OUT3 / OUT4.
• Output terminals: OUT1 / OUT2 / OUT3 / OUT4
• Output terminal: HVCC: connect the high voltage controlled positive, HGND connect the high voltage controlled negative
• Use: When IN1 is high level, the corresponding OUT1 voltage equal to HVCC, when IN1 is low, OUT1 voltage equal to HGND

Schematics:

Wiring: