Microchip Technology MCP4821-E/MS

Overview

MCP4821-E/MS from Microchip Technology is a 12-bit buffered voltage-output DAC with rail-to-rail output amplifier, internal 2.048V reference (50 ppm/°C), SPI interface (20 MHz max), 4.5 µs settling time, and selectable 1x/2x gain. It operates from 2.7V to 5.5V over –40°C to +125°C and is used for precision sensor calibration and portable instrumentation.

For engineers reviewing the MCP4821-E/MS datasheet, MCP4821-E/MS pinout, MCP4821-E/MS application, or MCP4821-E/MS equivalent, key selection criteria include guaranteed monotonic 12-bit resolution, ±4 LSb INL at +125°C, hardware/software shutdown modes, LDAC-synchronized output latching, and MSOP-8 package compatibility with analog ground isolation requirements.

Technical Context

The MCP4821-E/MS implements a resistive string DAC architecture ensuring low DNL (±0.25 LSb typical), low ratio-metric temperature coefficient, and fast settling. Its double-buffered registers enable synchronous updates via the LDAC pin, while the internal Power-on Reset (POR) circuit ensures high-impedance output until valid configuration.

It integrates a precision CMOS output amplifier supporting rail-to-rail swing (0.01 V to VDD – 0.04 V), programmable gain (1x or 2x), and stable operation into 5 kΩ loads with 100 pF capacitance. The 2.048V internal reference features 125 ppm/°C TC over –40°C to 0°C and 45 ppm/°C over 0°C to +85°C.

Key Specifications

Pinout & Package

The MCP4821-E/MS is housed in an 8-pin MSOP package (3.0 mm × 4.9 mm, 0.65 mm pitch) with exposed thermal pad electrically tied to VSS. Pin 1 is VDD; pins are arranged counterclockwise with CS (2), SCK (3), SDI (4), LDAC (5), SHDN (6), VSS (7), and VOUT (8).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage-output DAC applications.

Compared with MCP4822-E/MS and MCP4921-E/MS, the MCP4821-E/MS offers optimal balance of single-channel simplicity, integrated reference stability, and extended-temperature performance-making it ideal for space-constrained, self-contained calibration nodes.

Availability

MCP4821-E/MS is available at Aetrix Electronics and suitable for sensor calibration, portable instrumentation, and precision set-point trimming requiring stable component supply across automotive, industrial, and medical device production programs.

Supply support for MCP4821-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 microcontroller, mixed-signal, analog, and Flash-IP solutions, serving automotive, industrial, consumer, and communications markets.

The MCP48xx family was designed specifically for high-accuracy, low-power digital-to-analog conversion in embedded systems where integration, temperature resilience, and SPI simplicity are critical-targeting calibration, trimming, and programmable reference applications.

FAQ

What is the maximum SPI clock frequency supported by the MCP4821-E/MS?

The MCP4821-E/MS supports SPI clock frequencies up to 20 MHz at +25°C. At extended temperatures (–40°C to +125°C), timing specifications remain valid per AC characteristics table; design margin should account for tHI/tLO minimums of 15 ns and setup/hold times of 15 ns/10 ns respectively. This allows reliable interfacing with modern ARM Cortex-M and PIC32 microcontrollers without clock division.

How does the MCP4821-E/MS handle power-on initialization?

The MCP4821-E/MS incorporates an internal Power-on Reset (POR) circuit that holds the output in high-impedance state (~500 kΩ) until VDD exceeds VPOR (1.85V min) and a valid 16-bit write command is received with LDAC meeting low-threshold conditions. This prevents undefined output transients during power ramp-up and ensures deterministic startup behavior in safety-critical systems.

Can the MCP4821-E/MS operate with a 3.3V supply and still achieve rail-to-rail output?

Yes. The MCP4821-E/MS operates from 2.7V to 5.5V and delivers rail-to-rail output swing: VOUT ranges from 0.01 V to VDD – 0.04 V with 1 LSb accuracy maintained across the full 10 mV to (VDD – 40 mV) window. At 3.3V supply, this yields usable output from 10 mV to 3.26 V-sufficient for most 3.3V-system references and sensor interfaces.

What is the purpose of the exposed thermal pad (EP) on the MCP4821-E/MS MSOP package?

The exposed thermal pad (EP) on the MCP4821-E/MS MSOP package is internally connected to VSS and must be soldered to a PCB copper pour tied to analog ground. It reduces thermal resistance (θJA = 211°C/W for MSOP), improves long-term reliability under continuous load, and enhances analog performance by lowering ground impedance and minimizing thermal drift in the output amplifier and reference circuitry.

Does the MCP4821-E/MS support simultaneous multi-DAC updates?

Yes. The MCP4821-E/MS uses double-buffered registers and an asynchronous LDAC pin to enable synchronized output updates across multiple devices. When LDAC is asserted low, all MCP4821-E/MS units sharing the same LDAC line update their VOUT simultaneously-eliminating inter-channel glitches in multi-axis control or phased-array systems.