MCP3421 18 Bit ADC

MCP3421 18-Bit ADC

I2C Interface and Onboard Reference

The 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. The MCP3421 device performs conversions at rates of 3.75, 15, 60 or 240 samples per second depending on user controllable configuration bit settings using the two-wire I2C™ compatible serial interface. This device has an onboard programmable gain amplifier (PGA). User can select the PGA gain of x1, x2, x4, or x8 before the analog-to-digital conversion takes place. This allows the MCP3421 device to convert a smaller input signal with high resolution. The device has two conversion modes:

1. Continuous mode 
   
2. One-Shot mode.
   

In One-Shot mode, the device enters a low current standby mode automatically after one conversion. This reduces current consumption greatly during idle periods. The MCP3421 device can be used for various high accuracy analog-to-digital data conversion applications where ease of use, low power consumption and small footprint are major considerations.

Features of MCP3421

• 18-bit resolution
  
• Small 6-lead SOT-23 packaging
  
• Differential input operation
  
• On-board voltage reference with 5 ppm/°C drift
  
• On-board PGA, gains of 1, 2, 4, 8
  
• Programmable data rate options
  

1. 3.75 SPS (18 bits)
   
2. 15 SPS (16 bits)
   
3. 60 SPS (14 bits)
   
4. 240 SPS (12 bits)
   

• INL 10 ppm of FSR max
  
• Low current consumption, 145 µA at 3V
  
• One-shot or continuous conversion options
  
• Supports I2C™ serial interface
  
• Extended temperature range: -40°C to +125°C