{"product_id":"soldered-electrochemical-h2s-gas-sensor-breakout-qwiic","title":"Soldered Electrochemical H2S Gas Sensor Breakout (Qwiic)","description":"\u003cp\u003eThis board measures hydrogen sulphide (H2S) with an \u003cstrong\u003eSGX-4H2S-300\u003c\/strong\u003e electrochemical cell. The \u003cstrong\u003eLMP91000\u003c\/strong\u003e analog front end biases the cell and turns its current into a voltage, a \u003cstrong\u003e16-bit ADS1115\u003c\/strong\u003e ADC converts that voltage, and an \u003cstrong\u003eATtiny404\u003c\/strong\u003e talks to both chips for you, so your microcontroller sees a single I2C device.\u003c\/p\u003e \u003cp\u003e\u003cbr\u003e\u003c\/p\u003e \u003cp\u003eThe cell covers \u003cstrong\u003e0 to 300 ppm\u003c\/strong\u003e and reaches 90% of a step in under 30 s. It works from -30 to 50 °C and 15 to 90% RH. You set the front end over I2C and give the libraries the cell's sensitivity; they also include a zero calibration routine for clean air. The ADS1115's other three inputs, AIN1 to AIN3, are on a header for your own analog signals.\u003c\/p\u003e \u003cp\u003e\u003cbr\u003e\u003c\/p\u003e \u003cp\u003eConnect the board with either of the two \u003cstrong\u003eQwiic\u003c\/strong\u003e connectors or the 2.54 mm headers. It runs from \u003cstrong\u003e3.3 V\u003c\/strong\u003e; there is no regulator, so the header and the Qwiic connectors share one 3.3 V supply. The default address is \u003cstrong\u003e0x30\u003c\/strong\u003e; the three DIP switches move it from 0x30 to 0x37, so up to eight boards share one bus. The front end's analog output VOUT and the ADC's ALERT pin are on the header too. There are libraries for Arduino and MicroPython, plus an ESP-IDF component and an ESPHome component.\u003c\/p\u003e","brand":"Soldered Electronics","offers":[{"title":"Default Title","offer_id":66392709955933,"sku":"333331","price":69.95,"currency_code":"EUR","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0990\/5029\/1549\/files\/333331_photo_459a7b.webp?v=1793960627","url":"https:\/\/soldered.com\/products\/soldered-electrochemical-h2s-gas-sensor-breakout-qwiic","provider":"Soldered Electronics","version":"1.0","type":"link"}