Industrial Digital In 4 Bricklet


The Industrial Digital In 4 Bricklet is discontinued and is no longer sold. The Industrial Digital In 4 Bricklet 2.0 is the recommended replacement.


  • 4 channel digital input
  • Input voltages up to 36V (DC)
  • Galvanically isolated
  • Groupable


The Industrial Digital In 4 Bricklet can be used to extend Bricks by four galvanically isolated digital inputs. The input voltage can be up to 36 volts (DC).

Input isolation permits the usage without a direct electrical connection, such that ground loops can be prevented and an additional degree of safety is added.

Typical applications are the interfacing of industrial controllers, such as PLC's or frequency converters, or the usage in environments were electrical ground levels can not be connected.

If you need more then four inputs, you can add another Industrial Digital In 4 Bricklet and group these together. If you do this, you have eight inputs which can read simultaneously in contrast to read both Bricklets successively. Grouping is only possible for Bricklets connected to one Brick. Thus you can group up to four Industrial Bricklets on a Master Brick or two on other Bricks.

Technical Specifications

Property Value
Current Consumption 1mA
Input Type Four optocoupled inputs (including 4.7kΩ series resistor)
Input Current Depending on input voltage, ca. 1mA/5V, ca. 5mA/24V
Maximum Input Voltage 36V (DC)
Low Level Voltage 0-2V
High Level Voltage 3-36V
Isolation 5000Vrms (optocoupler value)
Dimensions (W x D x H) 40 x 40 x 11mm (1.57 x 1.57 x 0.43")
Weight 8g



The Industrial Digital In 4 Bricklet has an 8 pole terminal. With it you can access the four inputs. Each input is connected to one LED inside the optocoupler.

To use one input connect it as depicted below:

Industrial Digital In 4 Terminals

Test your Industrial Digital In 4 Bricklet

To test a Industrial Digital In 4 Bricklet you need to have Brick Daemon and Brick Viewer installed. Brick Daemon acts as a proxy between the USB interface of the Bricks and the API bindings. Brick Viewer connects to Brick Daemon. It helps to figure out basic information about the connected Bricks and Bricklets and allows to test them.

Connect the Industrial Digital In 4 Bricklet to a Brick with a Bricklet Cable. Additionally connect a voltage source to one of the Bricklet inputs. For testing purposes we have connected a battery (see picture below).

Industrial Digital In 4 Bricklet setup

If you connect the Brick to the PC over USB, you should see a new tab named "Industrial Digital In 4 Bricklet" in the Brick Viewer after a moment. Select this tab.

If everything went as expected you can change the state of the input channel by connecting and disconnecting the battery.

Industrial Digital In 4 Bricklet in Brick Viewer

After this test you can go on with writing your own application. See the Programming Interface section for the API of the Industrial Digital In 4 Bricklet and examples in different programming languages.


A laser-cut case for the Industrial Digital In 4 Bricklet is available.

Case for Industrial Digital In 4 Bricklet

The assembly is easiest if you follow the following steps:

  • Screw spacers to the Bricklet,
  • screw bottom plate to bottom spacers,
  • build up side plates,
  • plug side plates into bottom plate and
  • screw top plate to top spacers.

Below you can see an exploded assembly drawing of the Industrial Digital In 4 Bricklet case:

Exploded assembly drawing for Industrial Digital In 4 Bricklet

Hint: There is a protective film on both sides of the plates, you have to remove it before assembly.

Programming Interface

See Programming Interface for a detailed description.

Language API Examples Installation
C/C++ API Examples Installation
C# API Examples Installation
Delphi/Lazarus API Examples Installation
Go API Examples Installation
Java API Examples Installation
JavaScript API Examples Installation
LabVIEW API Examples Installation
Mathematica API Examples Installation
MATLAB/Octave API Examples Installation
MQTT API Examples Installation
openHAB API Examples Installation
Perl API Examples Installation
PHP API Examples Installation
Python API Examples Installation
Ruby API Examples Installation
Rust API Examples Installation
Shell API Examples Installation
Visual Basic .NET API Examples Installation
Modbus API