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Soldered Electrochemical Cl2 Gas Sensor Breakout (Qwiic)

This board measures chlorine (Cl2) from 0 to 10 ppm with an SGX-4CL2 electrochemical cell. An LMP91000 analog front end biases the cell and turns its current into a voltage, a 16-bit ADS1115 converts it, and an ATtiny404 talks to both chips for you, so your microcontroller sees one I2C device, at address 0x30 as shipped.

Purple gas sensor breakout seen at an angle, with two Qwiic connectors, a three-way ADDRESS switch, two rows of header pads and the round gas cell underneath
The breakout with the gas cell underneath
Top of the gas sensor breakout: Qwiic connectors on the left and right, the ADDRESS switch top left, labelled header pads along the top and bottom edges and a GND, UPDI, 3V3 header on the right
Top side
Underside of the breakout with the round gas cell in the middle, header labels along the top and bottom edges and a list of gas names on each side
Underside with the gas cell

This documentation is for​

Purple gas sensor breakout seen at an angle, with two Qwiic connectors, a three-way ADDRESS switch, two rows of header pads and the round gas cell underneathProductSoldered Electrochemical Cl2 Gas Sensor Breakout (Qwiic)Chlorine sensor board with an SGX-4CL2 cell for 0 to 10 ppm, read over Qwiic.SKU 333332ShopBuy it on our shopPrice, stock and every variant of this product in the Soldered shop.https://soldered.com/products/soldered-electrochemical-cl2-gas-sensor-breakout-qwiicOpen the shop page

At a glance​

InterfaceI2C over Qwiic or header, address 0x30 (0x30 to 0x37 by switch)
Main ICLMP91000 front end, ADS1115 16-bit ADC, ATtiny404 bridge
Gas cellSGX-4CL2 electrochemical, chlorine (Cl2)
Range0 to 10 ppm, 0.1 ppm resolution (typical, electronics dependent), T90 under 60 s
Voltage3.3 V only, no regulator
Connectors2x Qwiic, 2.54 mm headers
Dimensions38 x 38 mm
Environments-20 to 50 °C, 15 to 90% RH

What's in the box​

QtyItemNotes
1Soldered Electrochemical Cl2 Gas Sensor Breakout (Qwiic) (main product)SKU 333332
1Header pins (unsoldered)For the board's 2.54 mm header pads. The board itself is not breadboard compatible: wire the soldered pins with jumper wires.