Microchip Technology MCP3461-E/ST

Overview

MCP3461-E/ST from Microchip Technology is a single-channel, 16-bit delta-sigma analog-to-digital converter (ADC) with programmable gain (0.33x–64x), up to 153.6 ksps data rate, and integrated temperature sensor. It features 97.2 dB SINAD, ultra-low full shutdown current (< 5 µA), and operates across –40°C to +125°C for precision industrial sensing applications including pressure and strain transducers.

For engineers reviewing the MCP3461-E/ST datasheet, MCP3461-E/ST pinout, MCP3461-E/ST application, or MCP3461-E/ST equivalent, key selection criteria include differential input support, SPI interface timing compliance at 20 MHz, RMS effective resolution ≥15.5 bits, burnout current sources for sensor diagnostics, and secure register locking via 8-bit key.

Technical Context

The MCP3461-E/ST implements a second-order delta-sigma modulator with analog gain stage followed by SINC3 digital filtering and 16-bit offset/gain calibration registers. Its internal sequencer (SCAN mode) supports automatic multiplexed conversions using a 24-bit timer, eliminating MCU intervention during continuous acquisition.

Security is enforced via dual 16-bit CRCs-one for SPI data and one for configuration integrity-and an 8-bit secure key lock for the register map. The device accepts either internal RC oscillator (3.3–6.6 MHz) or external clock (1–20 MHz), with dedicated IRQ pin for synchronization and MCLKIN/IRQ/MDAT pin sharing configurable per mode.

Key Specifications

Pinout & Package

Package: 20-Lead TSSOP (6.5 mm × 4.4 mm × 1 mm), leaded, RoHS-compliant. Exposed pad not present in TSSOP variant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS1263IPW and MCP3561-E/ST, the MCP3461-E/ST uniquely combines secure register locking, burnout diagnostics, and SCAN-mode autonomy-making it optimal for certified industrial field devices requiring reduced firmware overhead and tamper-resistant configuration.

Availability

MCP3461-E/ST is available at Aetrix Electronics and suitable for precision sensor transducers, factory automation I/O modules, and portable instrumentation requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MCP3461-E/ST 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 MCP3461-E/ST belongs to Microchip's precision delta-sigma ADC product line, engineered specifically for high-accuracy sensor signal conditioning in space-constrained, thermally demanding applications where diagnostic integrity and configuration security are mandatory.

FAQ

What is the maximum SPI clock frequency supported by the MCP3461-E/ST?

The MCP3461-E/ST supports up to 20 MHz SPI clock frequency when DVDD is ≥2.7 V, and up to 10 MHz when DVDD is between 1.8 V and 2.7 V. Timing parameters-including tSU (5 ns), tHD (10 ns), and tDO (25 ns)-are fully characterized across this range and meet industrial noise immunity requirements with Schmitt-triggered inputs.

Does the MCP3461-E/ST include hardware-based security features?

Yes, the MCP3461-E/ST includes multiple hardware security features: 16-bit CRC validation for both SPI data transfers and configuration writes, plus register map lock enabled by an 8-bit secure key. These features prevent unauthorized reconfiguration and ensure data integrity in secure industrial communication networks-critical for deployments governed by IEC 62443.

Can the MCP3461-E/ST perform automatic channel scanning without MCU intervention?

Yes, the MCP3461-E/ST supports SCAN mode with an integrated 24-bit timer and internal conversion sequencer. Once configured, it autonomously cycles through selected channels (e.g., CH0 → temperature sensor → CH0) with programmable inter-channel delays, reducing host MCU load and enabling deterministic sampling in real-time control loops.

What is the purpose of the burnout current sources in the MCP3461-E/ST?

The burnout current sources in the MCP3461-E/ST inject a known current (typically ~200 nA) into CH0 and CH1 to detect open-circuit or short-circuit conditions in connected sensors. This enables real-time wire-break diagnostics in pressure, load cell, or RTD applications-eliminating the need for external test circuitry and improving system reliability certification.

How does the MCP3461-E/ST handle reference voltage configuration?

The MCP3461-E/ST uses differential reference inputs (REFIN+ and REFIN−) to define its full-scale range as ±VREF/GAIN. VREF must be between 0.6 V and AVDD, with REFIN− typically tied to AGND for single-ended operation. The device supports ratiometric measurements and rejects supply variations with –76 dB AVDD PSRR (gain-dependent), ensuring stable scaling across voltage fluctuations.