A CircuitPython driver for the AMS AS7343 14-channel spectral sensor. This device provides high-resolution spectral measurements across the visible and near-infrared spectrum, making it ideal for:
- Color measurement and classification
- LED spectrum analysis
- Environmental light sensing
- Low-cost lab and educational tools
The AMS AS7343 is a spectral sensor offering readings from approximately 380nm to 1000nm. It includes:
- 14 photodiode channels: F1–F8, FZ, FY, FXL, NIR, and CLR
- Adjustable gain (0.5x to 2048x)
- Integration time in microseconds
- Internal SMUX (sensor multiplexer) to cycle through photodiode sets
- I2C interface (address 0x39)
This driver provides methods to set gain/integration time, select SMUX modes, perform full or partial scans, and manage power settings.
- Full 14-channel spectral measurement using read_all()
- SMUX mode selection for visible, NIR, and extended bands
- Low-power mode and sleep-after-interrupt (SAI)
- Saturation threshold checking
- Compatible with CircuitPython and Adafruit BusDevice
- Download the CircuitPython library bundle from https://circuitpython.org/libraries
- Copy the following into the lib/ directory on your device: - as7343.py (from this repo) - adafruit_bus_device (from the bundle)
import board
import as7343
import time
i2c = board.STEMMA_I2C()
sensor = as7343.AS7343(i2c)
sensor.gain = as7343.GAIN_64X
sensor.integration_time = 100000
data = sensor.read_all()
for ch, val in data.items():
print(f"{ch}: {val}")SMUX Read Example:
sensor.read_smux_mode(as7343.SMUX_VISIBLE) sensor.read_smux_mode(as7343.SMUX_NIR) sensor.read_smux_mode(as7343.SMUX_FZF5)
Power Management:
sensor.enable_low_power_mode(True) sensor.enable_sleep_after_interrupt(True) sensor.shutdown() sensor.wake()
Threshold Check:
alerts = sensor.check_thresholds(60000)
for ch, value in alerts:
print(f"High reading: {ch} = {value}")
- F1, F2, F3, F4 – Violet to green (405–515 nm)
- FY, F5 – Green/yellow (~555–560 nm)
- F6, F7, F8 – Red to deep red (640–745 nm)
- FZ, FXL – Additional narrowbands (450, 600 nm)
- NIR – Near infrared (~855 nm)
- CLR – Clear (broadband)
MIT License
Joe Pardue https://github.com/joepardue/AS7343-circuitpython-bundle