Microchip Technology MCP3204-CI/P

Overview

MCP3204-CI/P from Microchip Technology Inc. is a 12-bit successive approximation analog-to-digital converter (ADC) with on-chip sample-and-hold, SPI serial interface, and four single-ended or two pseudo-differential input channels. It operates from 2.7V to 5.5V, delivers up to 100 ksps at 5V, and features ±2 LSB max INL and ±1 LSB max DNL - optimized for sensor interface and battery-powered data acquisition in industrial temperature range (–40°C to +85°C).

For engineers reviewing the MCP3204-CI/P datasheet, MCP3204-CI/P pinout, MCP3204-CI/P application, or MCP3204-CI/P equivalent, key selection criteria include its 12-bit resolution, SPI mode 0/1 compatibility, low 400 µA active current at 5V, 14-pin PDIP package, and guaranteed performance across –40°C to +85°C without external reference buffering.

Technical Context

The MCP3204-CI/P implements a SAR architecture with internal 20 pF sample capacitor and 1.5-clock-cycle acquisition time starting on the fourth rising CLK edge after the start bit. Its analog front-end supports programmable single-ended or pseudo-differential channel configuration via SPI command bits (SGL/DIFF + D2:D0), enabling flexible signal routing without hardware reconfiguration.

It uses a 4-wire SPI interface (CS/SHDN, CLK, DIN, DOUT) compatible with modes 0,0 and 1,1, with data output synchronized to falling CLK edges. The device enters standby (500 nA typical) when CS/SHDN is high, and its VREF input directly sets the full-scale range (0.25V to VDD), supporting both internal and external reference topologies.

Key Specifications

Pinout & Package

The MCP3204-CI/P is supplied in a 14-lead PDIP package (0.300" wide), with pin 1 marked by notch or dot. Pin functions are electrically validated per DS21298E and confirmed for this variant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-bit SAR ADC applications.

Compared with ADS7822U, MCP3204-CI/P offers integrated sample-and-hold and programmable pseudo-differential inputs at lower power, while MCP3204-I/P is functionally identical but shares the same industrial qualification - making MCP3204-CI/P the assured choice for harsh-environment designs.

Availability

MCP3204-CI/P is available at Aetrix Electronics and suitable for sensor interface, process control, and battery-operated systems requiring stable component supply, long-term manufacturability, and traceable sourcing from authorized channels.

Supply support for MCP3204-CI/P 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 global semiconductor company specializing in microcontrollers, analog devices, and interface ICs, with emphasis on reliability, longevity, and embedded-systems integration.

The MCP3204-CI/P belongs to Microchip's precision SAR ADC product line, designed specifically for cost-sensitive, low-power industrial and instrumentation applications where 12-bit accuracy, SPI simplicity, and robust temperature performance are essential.

FAQ

What is the maximum sampling rate of the MCP3204-CI/P at 3.3V supply?

The MCP3204-CI/P achieves a maximum sampling rate of 50 ksps when operated at VDD = 2.7V; at 3.3V, it supports up to 75 ksps (interpolated from datasheet curves and verified by Microchip's application note AN1126). This rate maintains full 12-bit linearity and ±2 LSB INL specification across the industrial temperature range. The MCP3204-CI/P clock frequency must be scaled accordingly - e.g., ~1.5 MHz at 3.3V - to ensure proper sample capacitor charging.

Does the MCP3204-CI/P require an external reference voltage?

No, the MCP3204-CI/P can operate with VREF tied to VDD for ratiometric measurements, or accept an external precision reference (0.25V to VDD). When using VDD as reference, the ADC's LSB size becomes VDD/4096 - ideal for sensor systems where excitation and reference share the same rail. The MCP3204-CI/P does not include an internal reference; external buffering is recommended for noisy environments or high-accuracy applications.

How is pseudo-differential mode configured on the MCP3204-CI/P?

Pseudo-differential mode is selected per-conversion by sending a 4-bit SPI command: start bit = 1, SGL/DIFF bit = 0, followed by D2:D0 = 000 to 111 (per Table 5-1 in DS21298E). For example, command "10000" configures CH0 as IN+ and CH1 as IN–. The MCP3204-CI/P then measures the difference (IN+ − IN–) with IN– limited to ±100 mV relative to VSS. This mode rejects common-mode noise without requiring a dedicated differential amplifier.

What is the purpose of the null bit in the MCP3204-CI/P SPI output stream?

The null bit is the first bit output on DOUT after the 4-bit command is received; it is always low and serves as a timing alignment marker indicating that conversion has completed and the 12-bit result (MSB first) follows immediately. This null bit ensures deterministic synchronization between host MCU and MCP3204-CI/P, especially critical when interfacing with hardware SPI peripherals that expect fixed-length frames. Its presence confirms successful command execution before data capture begins.

Can the MCP3204-CI/P be used with a 1.8V microcontroller SPI interface?

No - the MCP3204-CI/P's digital I/O thresholds require VIH ≥ 0.7×VDD and VIL ≤ 0.3×VDD. With VDD = 2.7V minimum, VIH ≥ 1.89V and VIL ≤ 0.81V, making direct 1.8V logic incompatible. Level translation (e.g., TXB0104 or discrete MOSFET buffer) is required between a 1.8V MCU and the MCP3204-CI/P. Alternatively, operate the MCP3204-CI/P at 3.3V and translate only the SPI lines, preserving its full 12-bit performance and industrial temperature rating.