THERMAL IMAGING // LWIR SENSOR BREAKOUT & SDK

FLIR Lepton LWIR Thermal Camera Breakout Board & Reference Code

The FLIR Lepton is a compact long-wave infrared (LWIR) camera core with 80x60 or 160x120 pixel resolution in a package smaller than a US dime. Pure Engineering developed the open-source FLIR Lepton Breakout Board (25 mm x 24 mm) with onboard 2.8 V and 1.2 V regulators and a 25 MHz master clock. Engineers can capture VoSPI thermal video and control I2C settings from a single 3 V to 5.5 V supply.

Architecture & Technical Specifications

Hardware Architecture & Features

Single 3 V to 5.5 V input supply with onboard low-noise 2.8 V, 1.2 V, and 25 MHz oscillator rails.
Compact 25 mm x 24 mm PCB with 32-pin socket for 50-degree shuttered, 50-degree, and 25-degree Lepton cores (500-0643-00, 500-0659-01, 500-0690-00).
Standard 8-pin 100-mil header exposing SCL, SDA, VIN, GND, CLK, MISO, MOSI, and CS.
Direct jumper-wire compatibility with Raspberry Pi, STM32 Nucleo (NUCLEO-F401RE), STM32F3Discovery, and Arduino Due.
For driverless USB UVC video streaming without custom SPI DMA code, pair the Lepton core with PureThermal 1, PureThermal 2, or PureThermal Mini.

Firmware, Software & Integration

Open-source Raspberry Pi capture software and Python library (PureEngineering/LeptonModule and https://github.com/groupgets/pylepton).
ARM mbed example firmware for STM32 Nucleo boards (Nucleo_lepton) and Arduino Due libraries.
Full access to the FLIR Lepton I2C Command and Control interface (FFC shutter control, telemetry rows, AGC, and radiometry).
Note on 8-bit MCUs: The Arduino Uno lacks sufficient RAM and SPI clock speed to buffer VoSPI frames in C.

Technical Notes & Reference Details

8-Pin Header Pinout: SCL (I2C Clock), SDA (I2C Data), VIN (3 V to 5.5 V), GND, CLK (SPI Clock), MISO (SPI Data Out), MOSI (SPI Data In), and CS (SPI Chip Select).
Raspberry Pi Bring-Up: Connect the 8-pin header with female-to-female jumper wires, enable SPI and I2C in raspi-config, and run raspberrypi_capture or raspberrypi_video from PureEngineering/LeptonModule.
Troubleshooting: If the video window shows a black or red square, reseat the Lepton core firmly into the 32-pin socket or briefly toggle CS to 3.3 V and back to CE0/CE1.