Analog Devices Inc./Maxim Integrated MAX1202ACPP+

Overview

MAX1202ACPP+ from Maxim Integrated is a 12-bit, 8-channel serial analog-to-digital converter (ADC) designed for mixed 5V analog / 3V digital supply systems. It integrates an on-chip track/hold, 4.096V internal reference, SPI/MICROWIRE-compatible 4-wire interface, and supports unipolar/bipolar input modes with ±0.5 LSB INL (A-grade). It delivers 133 kSPS sampling rate at 1.5 mA operating current and enables sub-10 µA shutdown between conversions - ideal for battery-powered data acquisition in medical instruments and portable process controllers.

For engineers reviewing the MAX1202ACPP+ datasheet, MAX1202ACPP+ pinout, MAX1202ACPP+ application, or MAX1202ACPP+ equivalent, this page provides verified technical context, real-world design meaning of key specs, validated pin functions, confirmed alternative parts with documented differences, and precise application mapping - all derived from Maxim's official datasheet Rev 3 (2012) and product documentation.

Technical Context

The MAX1202ACPP+ uses successive-approximation register (SAR) architecture with integrated track/hold and internal 4.096V reference buffer. Its analog front-end supports both single-ended (8-channel) and pseudo-differential (4-channel) inputs, with configurable unipolar/bipolar ranges determined by REF voltage and control-byte settings.

It operates in dual clock modes: internal clock (1.7 MHz typical) or external serial clock up to 2 MHz. The 4-wire serial interface (CS, SCLK, DIN, DOUT + SSTRB strobe) is natively compatible with SPI (CPOL=0, CPHA=0) and MICROWIRE, enabling direct connection to TMS320-family DSPs without level-shifting or glue logic.

Key Specifications

Pinout & Package

MAX1202ACPP+ is housed in a 20-pin plastic dual in-line package (PDIP), RoHS-compliant and lead-free (+ suffix). Pin layout matches industry-standard 0.3-inch wide DIP footprint, compatible with through-hole prototyping and legacy PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7822U and MAX11126ETE+, the MAX1202ACPP+ uniquely combines internal 4.096V reference, 8-channel MUX, bipolar/single-ended flexibility, and PDIP packaging - making it optimal for legacy-compatible, low-BOM-count, mixed-voltage industrial data loggers.

Availability

MAX1202ACPP+ is available at Aetrix Electronics and suitable for portable medical sensors, industrial process monitoring, battery-powered test equipment, and automotive diagnostic tools requiring stable component supply and long-term obsolescence management.

Supply support for MAX1202ACPP+ 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

Maxim Integrated (now part of Analog Devices) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, medical, and communications applications.

The MAX1202 series belongs to Maxim's precision data acquisition portfolio, engineered for mixed 5V/3V supply environments where integration, low power, and reference stability are critical - especially in portable and distributed sensing systems.

FAQ

What is the maximum sampling rate achievable with MAX1202ACPP+?

The MAX1202ACPP+ achieves a maximum sampling rate of 133 kSPS when using a 2 MHz external serial clock and 15-clock conversion cycles. This rate is fixed by the internal SAR timing architecture and cannot be increased beyond 133 kSPS even with faster clocks, as the conversion requires exactly 12 decision cycles plus overhead. The MAX1202ACPP+ does not support oversampling or decimation modes.

Does MAX1202ACPP+ support true differential input mode?

No, the MAX1202ACPP+ implements pseudo-differential input architecture. In differential mode, only the positive input (IN+) is actively sampled; the negative input (IN-) serves as a stable reference point that must remain within ±0.1 LSB of GND. True differential sampling - where both inputs are simultaneously acquired - is not supported. This architecture simplifies design but requires careful grounding and bypassing of the IN- node.

Can MAX1202ACPP+ operate with a 3.3V analog supply?

No, the MAX1202ACPP+ requires a +5V ±5% analog supply (VDD) per its Absolute Maximum Ratings and Electrical Characteristics tables. While the digital interface is 3V-compatible via the VL pin, the analog core, reference buffer, and multiplexer are specified only for 5V operation. Using 3.3V on VDD will result in undefined behavior, failed conversions, or permanent damage.

How is the internal reference voltage trimmed on MAX1202ACPP+?

The internal 4.096V reference on MAX1202ACPP+ is trimmed using the REFADJ pin, which adjusts the reference buffer gain over a ±1.5% range. A resistor divider or DAC can be connected to REFADJ to fine-tune output voltage; the nominal gain is 1.68×, so applying 2.44V to REFADJ yields 4.096V at REF. No external trimming potentiometer is required for standard operation.

What happens to MAX1202ACPP+ outputs when CS is high?

When CS is high, both DOUT and SSTRB enter high-impedance (three-state) mode regardless of clock or data activity. This allows multiple MAX1202ACPP+ devices to share the same serial bus. The device also automatically powers down its analog circuitry after ~1 µs, reducing supply current to ~30 µA (fast power-down) unless SHDN is actively pulled low for full 2 µA shutdown.