Microchip Technology MCP3426A3T-E/MS

Overview

MCP3426A3T-E/MS from Microchip Technology is a 16-bit ΔΣ analog-to-digital converter with two differential input channels, on-board 2.048V ±0.05% voltage reference, programmable gain amplifier (x1/x2/x4/x8), and I²C interface supporting standard/fast/high-speed modes. It delivers 15 SPS at 16-bit resolution, achieves ±10 ppm INL, and operates from 2.7V to 5.5V supply across –40°C to +125°C for precision sensor signal acquisition in battery-powered instrumentation.

For engineers reviewing the MCP3426A3T-E/MS datasheet, MCP3426A3T-E/MS pinout, MCP3426A3T-E/MS application, or MCP3426A3T-E/MS equivalent, key selection considerations include its factory-programmed I²C address, MSOP-8 package with exposed thermal pad, self-calibrating offset/gain per conversion, differential input impedance of 2.25 MΩ (PGA=1), and low 9 µA standby current in 16-bit one-shot mode.

Technical Context

The MCP3426A3T-E/MS implements a delta-sigma modulation architecture with integrated 3.2 pF sampling capacitor, on-chip oscillator, and sinc filter. Its PGA precedes the modulator to amplify weak signals before digitization, enabling full-scale input ranges from ±256 mV (PGA=8) to ±2.048 V (PGA=1).

Each conversion triggers automatic offset and gain calibration using the internal 2.048V reference, eliminating need for external calibration across temperature and supply variations. The device supports both one-shot (auto-standby) and continuous conversion modes, with configurable resolution–speed trade-offs: 16-bit/15 SPS, 14-bit/60 SPS, or 12-bit/240 SPS.

Key Specifications

Pinout & Package

The MCP3426A3T-E/MS is housed in an 8-pin MSOP package with exposed thermal pad (EP), requiring connection to VSS for thermal and electrical integrity. Pin numbering follows standard MSOP orientation (pin 1 = CH1+, pin 8 = SCL).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar precision ADC applications.

Compared with ADS1115IDGSR and MCP3421A0T-E/CH, the MCP3426A3T-E/MS uniquely balances dual-channel capability, per-conversion self-calibration, and ultra-low standby power-making it optimal for compact, battery-operated dual-sensor systems demanding long-term accuracy without host intervention.

Availability

MCP3426A3T-E/MS is available at Aetrix Electronics and suitable for portable instrumentation, industrial temperature monitoring, and battery-powered weigh scale designs requiring stable component supply, guaranteed long-term sourcing, and full traceability.

Supply support for MCP3426A3T-E/MS includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology Inc. is a leading provider of microcontrollers, analog components, and Flash-IP solutions, serving industrial, automotive, and consumer markets with high-reliability silicon and development tools.

The MCP342X series was designed specifically for high-accuracy, low-power sensor signal conditioning in space-constrained and energy-sensitive applications-emphasizing integrated references, self-calibration, and robust I²C interfacing.

FAQ

What is the factory-programmed I²C address of the MCP3426A3T-E/MS?

The MCP3426A3T-E/MS has its I²C address permanently programmed at the factory and cannot be modified via external pins. Its default 7-bit address is 0x68 (1101000b), corresponding to the "A3" suffix in the part number. This fixed addressing simplifies system integration in single-ADC configurations and avoids address conflicts in multi-device I²C buses where other MCP342X variants use configurable Adr0/Adr1 pins.

How does the MCP3426A3T-E/MS achieve ±10 ppm INL performance?

The MCP3426A3T-E/MS achieves ±10 ppm integral non-linearity through a combination of laser-trimmed on-die resistors in its delta-sigma modulator path, matched capacitor arrays in the switched-capacitor front end, and per-conversion self-calibration that corrects residual offset and gain errors. This specification is verified at 15 SPS in 16-bit mode with PGA=1 and applies across the full –40°C to +85°C operating range, ensuring consistent linearity without external trimming.

Can the MCP3426A3T-E/MS operate with a 2.7 V supply while maintaining full 16-bit performance?

Yes, the MCP3426A3T-E/MS fully supports 2.7 V to 5.5 V single-supply operation and maintains its specified 16-bit resolution, ±10 ppm INL, and 15 SPS data rate at 2.7 V. Electrical characteristics-including reference accuracy (2.048 V ±0.05%), PGA gain error (0.1%), and supply current (135 µA typical in continuous mode)-are guaranteed across this entire voltage range, enabling direct compatibility with Li-ion battery discharge profiles.

What is the role of the exposed thermal pad (EP) on the MCP3426A3T-E/MS MSOP-8 package?

The exposed thermal pad (EP) on the MCP3426A3T-E/MS is electrically connected to VSS and must be soldered to a dedicated VSS copper pour on the PCB for effective heat dissipation and noise reduction. It lowers thermal resistance (θJA = 211°C/W for MSOP-8), stabilizes analog ground potential, and improves ESD robustness. Leaving EP unconnected degrades thermal performance and may cause gain/offset drift under sustained conversion loads.

Does the MCP3426A3T-E/MS support single-ended input configurations?

Yes, the MCP3426A3T-E/MS supports single-ended operation by connecting the CHn− pin (e.g., CH1− or CH2−) to VSS while applying the signal to the corresponding CHn+ pin (e.g., CH1+). This configuration uses half the differential full-scale range (e.g., 0–2.048 V with PGA=1) and reduces common-mode rejection, but retains all other specifications including self-calibration, PGA gain options, and I²C interface functionality.