18 Bit ADC - MCP3421 - I2C Driver ESP8266

MCP3421 is a single channel, low-noise, high accuracy delta-sigma A/D converter with differential inputs and up to 18 bits of resolution in a small SOT-23-6 package. The on-board precision 2.048V reference voltage enables an input range of ±2.048V differentially.

The device uses a two-wire I2C compatible serial interface and operates from a single power supply ranging from 2.7V to 5.5V, has a decent price and looks like a good companion for our ESP8266 module.

I have run some tests and it’s looking quite well for a cheap ADC

  1. Test done in filtered environment - stable voltage
    MCP3421 - I2C ADC - ESP8266 Driver - Test in filtered environment - YouTube

  2. Test done in noisy environment - using real bus unfiltered voltage
    MCP3421 - I2C ADC - ESP8266 Driver - Test in noisy environment - YouTube

  3. Test done in noisy environment - values are printed directly on CBDB DevBoard LCD Display
    MCP3421 - I2C ADC - ES

For more details : http://www.esp8266-projects.com/2015/04/18-bit-adc-mcp3421-i2c-driver-esp8266.html

MCP3421 - 1 - Adapter Board - 1.jpg

MCP3421 - 4_1 - ADC LCD Output Test - 4_1.jpg