Microchip Technology MCP3421EV

Overview

MCP3421EV from Microchip Technology Inc. is a dedicated evaluation board for the MCP3421A0T-E/OT 18-bit delta-sigma analog-to-digital converter (ADC) in SOT-23-6 package. It provides direct access to VDD, GND, SDA, SCL, VIN+, VIN− test pads and supports I²C communication at up to 400 kHz. Designed for rapid ADC characterization, it enables configuration of continuous/conversion modes, 18-bit resolution, and 1× PGA gain via I²C commands using the PICkit Serial Analyzer.

For engineers reviewing the MCP3421EV datasheet, MCP3421EV pinout, MCP3421EV application, or MCP3421EV equivalent, this board serves as a validated hardware platform to verify I²C register writes, read conversion data (e.g., 0x0105AD = 1.0307 V), validate timing behavior including RDY bit assertion, and assess real-world sensor interface performance without custom PCB design.

Technical Context

The MCP3421EV implements a fixed-hardware interface to the MCP3421A0T-E/OT ADC, with factory-programmed I²C address 0xD0 (1101000b). It includes on-board 4.99 kΩ pull-up resistors on SDA/SCL, decoupling capacitors (0.1 µF and 10 µF), and LED D1 for VDD presence indication. No microcontroller is integrated - all I²C control must be supplied externally.

It supports both single-ended (VIN+ to GND, VIN− tied to GND) and differential input configurations. The board accepts external VDD (2.7–5.5 V) or derives power from the PICkit Serial Analyzer via JP1 jumper, with no voltage regulation or level-shifting circuitry present.

Key Specifications

Availability

MCP3421EV is available at Aetrix Electronics and suitable for precision sensor evaluation, industrial data acquisition prototyping, and embedded ADC validation requiring stable component supply, traceable sourcing, and documented reference design support.

Supply support for MCP3421EV 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 U.S.-based semiconductor company specializing in microcontrollers, analog devices, and development tools, certified to ISO/TS-16949:2002 and ISO 9001:2000.

The MCP3421EV belongs to Microchip's evaluation board product line, designed specifically to accelerate functional validation and firmware integration of the MCP3421 family of high-resolution I²C ADCs in sensor and measurement applications.

FAQ

What is the primary function of the MCP3421EV?

The MCP3421EV is an evaluation board built exclusively to demonstrate and validate the operation of the MCP3421A0T-E/OT 18-bit I²C ADC. It provides physical access to all critical signals - VDD, GND, SDA, SCL, VIN+, and VIN− - enabling engineers to perform real-time configuration, conversion readback, timing analysis, and sensor interface testing without designing custom hardware. The MCP3421EV does not contain any processing logic or firmware.

Does the MCP3421EV include a microcontroller?

No, the MCP3421EV does not include a microcontroller. It is a passive interface board centered around the MCP3421A0T-E/OT ADC IC. All I²C communication must be initiated externally - typically using the PICkit Serial Analyzer (P/N DV164122) or another I²C master device. The board contains only passive components (resistors, capacitors, LED) and the target ADC.

What is the I²C address of the MCP3421 on the MCP3421EV board?

The MCP3421 device on the MCP3421EV board has a fixed I²C address of 0xD0 (binary 1101000), with the R/W bit cleared for write operations. This address is factory-programmed and cannot be changed, as A2, A1, and A0 pins are hardwired to GND. Confirmation is provided in Section 1.2.1 of DS51793A and verified by the script examples (e.g., "D0" in WriteBlockAddrA8).

Can the MCP3421EV operate without the PICkit Serial Analyzer?

Yes, the MCP3421EV can operate without the PICkit Serial Analyzer. Users may supply their own I²C master (e.g., MCU, FPGA, or logic analyzer with I²C capability), provide external VDD (2.7–5.5 V) to the VDD test pad, and connect to SDA/SCL/VIN+/VIN−/GND. The board includes on-board pull-up resistors, so no external I²C bus termination is required. The PICkit Serial Analyzer is only one supported interface option.

What does the RDY bit indicate during data reads on the MCP3421EV?

During an I²C read sequence on the MCP3421EV, the fourth byte returned contains the RDY bit. When RDY = 0, the preceding three data bytes represent the most recent completed conversion. When RDY = 1 (as seen in the fifth repeated byte), the ADC is actively performing a new conversion and the latest result is not yet ready. This behavior is intrinsic to the MCP3421A0T-E/OT and is observable on the MCP3421EV using oscilloscope waveforms or script-based reads.