MCP3422A1-E/MC

Analog To Digital Converters (ADC) Overview

The MCP3422A1-E/MC is an 18-bit Delta-Sigma analog-to-digital converter featuring two differential input channels and an I²C serial interface. It integrates a 2.048V internal voltage reference, a programmable gain amplifier (PGA) with gains of 1, 2, 4, or 8, and an on-board oscillator. The device supports data rates of 3.75, 15, 60, or 240 samples per second corresponding to resolutions of 18, 16, 14, or 12 bits. It operates on a single supply voltage ranging from 2.7V to 5.5V and includes self-calibration for offset and gain errors during each conversion cycle.

Analog To Digital Converters (ADC) Feature Summary

• 18-bit resolution with differential inputs and integrated 2.048V reference
• Programmable Gain Amplifier (PGA) offering gains of 1x, 2x, 4x, or 8x
• I²C interface supporting Standard (100 kHz), Fast (400 kHz), and High Speed (3.4 MHz) modes
• Low power consumption: 135 µA typical in continuous mode at 3V

Analog To Digital Converters (ADC) Applications

• Portable instrumentation and consumer goods
• Temperature sensing using RTDs, thermistors, and thermocouples
• Bridge sensing for pressure, strain, and force measurements
• Weigh scales and battery fuel gauges

Analog To Digital Converters (ADC) Procurement Notes

Verify the package type matches the required PCB footprint, as the MCP3422 series is available in DFN-8, MSOP-8, and SOIC-8 packages. Confirm that the fixed I²C address configuration meets system bus requirements, as the MCP3422 lacks external address selection pins unlike the MCP3423/4 variants. Ensure pull-up resistors are selected appropriately for the chosen I²C clock speed.

Analog To Digital Converters (ADC) Selection Notes

Select this component when high accuracy and low noise are required for dual-channel differential signals. The fixed I²C address limits deployment to one device per bus segment unless level shifting or multiplexing is used. Consider the PGA settings to match the input signal amplitude to the ±2.048V reference range. Verify that the source impedance is low enough to charge the internal sampling capacitor within the conversion time.

Analog To Digital Converters (ADC) Part Context

This part belongs to the MCP342X family of low-power, high-resolution ADCs from Microchip Technology. Unlike the MCP3423 and MCP3424, which feature configurable I²C addresses via Adr0 and Adr1 pins, the MCP3422 has a factory-programmed fixed address. All electrical characteristics, including resolution, data rates, and power consumption, remain identical across the family members.

Analog To Digital Converters (ADC) Replacement Considerations

Direct pin-compatible replacements include other MCP3422 variants with different suffixes indicating package or temperature grade changes. Cross-family substitution with MCP3423 or MCP3424 requires addressing the I²C address conflict due to the fixed address of the MCP3422.