Open Colorimeter LED Boards

Each of the Open Colorimeter products ships with an LED mounted and ready to use. The LED included depends on the Open Colorimeter product:

Open Colorimeter & Multichannel Open Colorimeter: White LED board
UV Open Colorimeter: Select from 6 different UV options

White LED board (LEFT) and 275nm LED board (RIGHT)

We have designed a series of UV, visible and IR LED boards which can be used to customize the Open Colorimeters.

Open Colorimeter LED Board Design

All of the LED boards are designed with these same features in common:

Dimensions: 25.4 mm x 20 mm x 1.6 mm
Two 4-pin JST SH connectors for connecting to the light sensor and PyBadge
Four M2.5 through holes for mounting to the cuvette holder
Surface mount LED in the center

New: Current Controlled Design

We have added additional components to the LED board design. Earlier versions (Basic LED) without this additional circuitry operated only from a 3.3V input voltage which required modifications to the PyBadge. With the new design, this is no longer required as the on-board voltage regulator enables operation from 3.3V to 5V input voltage.

In addition, the new design includes an active 16mA (or 24mA) constant current LED driver which maintains stable LED current.

Links to the open hardware KiCad design files:

Current controlled LEDs: https://github.com/iorodeo/i_control_led
Basic LED: https://github.com/iorodeo/i2c_led

Customizing the LED Wavelength

The Open Colorimeter and UV Open Colorimeter can be additionally customized to use multiple different wavelength options. Instructions for changing LEDs are on the Getting Started Guide page.

LEDs can be categorized into two groups based on which light sensor/instrument you are using:

Visible and IR LEDs: For use with the TSL2592 sensor/Open Colorimeter
- Note: The Multichannel Open Colorimeter uses the AS7341 sensor with filters providing the different wavelength channels. The default white LED shipped with this Colorimeter version is suitable. You can probably still customize further with the visible/IR LEDs to improve specific channel sensitivity though we haven't tested that yet
UV LEDs: For use with the AS7331 sensor/UV Open Colorimeter

Wavelength Options - Visible and IR

Wavelength Options - UV

View LED Product Details

Open Colorimeter Product Guide

Documentation site for the Open Colorimeter, Multi-Channel Colorimeter, UV Open Colorimeter & Open Colorimeter Plus

Product Guide Home Page