Analog Devices Inc./Maxim Integrated MAX149ACPP

Overview

MAX149ACPP from Maxim Integrated is a 10-bit, 8-channel serial analog-to-digital converter (ADC) with integrated track/hold, software-configurable unipolar/bipolar and single-ended/differential inputs, internal 2.5V reference, and SPI/QSPI/MICROWIRE-compatible 4-wire interface. It operates from a single +2.7V to +5.25V supply, achieves 133ksps sampling rate, and draws only 1.2mA at 3V - enabling use in portable data loggers, battery-powered medical instruments, and low-power process control systems.

For engineers reviewing the MAX149ACPP datasheet, MAX149ACPP pinout, MAX149ACPP application, or MAX149ACPP equivalent, this page delivers verified technical context, exact pin functions, real-world application mappings, and validated alternative parts - all grounded in the official MAX149ACPP specification and package documentation.

Technical Context

The MAX149ACPP employs successive-approximation register (SAR) architecture with an integrated track/hold circuit, supporting both internal clock mode (1.8MHz typical) and external serial clock mode (up to 2.0MHz). Its analog front-end allows flexible input configuration: 8 single-ended or 4 pseudo-differential channels, with COM pin serving as common-mode reference and zero-code anchor.

It features dual power-down modes - full shutdown (<1µA) and fast power-down (30–70µA for MAX149), both programmable via control byte PD bits. The internal 2.5V reference (±0.5 LSB INL, ±30ppm/°C TC) is buffered and adjustable via REFADJ (±1.5% range), eliminating need for external reference components in most designs.

Key Specifications

Pinout & Package

MAX149ACPP is housed in a 20-pin plastic DIP (PDIP) package with 0.3-inch body width, RoHS-compliant and lead-free per + suffix designation. Pin spacing is 0.1 inch, compatible with standard through-hole prototyping and industrial PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 10-bit serial ADC applications.

Compared with ADS7822U and MAX11126ETE+, the MAX149ACPP uniquely combines 20-pin PDIP packaging, internal 2.5V reference, 8-channel MUX, and three-level SHDN control - making it optimal for cost-sensitive, repairable, and low-component-count industrial instrumentation.

Availability

MAX149ACPP is available at Aetrix Electronics and suitable for portable data logging, battery-powered medical devices, and industrial process control applications requiring stable component supply, long-lifecycle support, and through-hole manufacturability.

Supply support for MAX149ACPP 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 MAX148/MAX149 product line was designed for low-power, multi-channel data acquisition in space- and energy-constrained systems - emphasizing integrated functionality (MUX, T/H, ref, interface) to minimize external components and PCB area.

FAQ

What is the operating temperature range for MAX149ACPP?

The MAX149ACPP is rated for 0°C to +70°C ambient operation, as indicated by the "C" grade suffix in its ordering code. This commercial-grade temperature range is validated across all electrical specifications including INL (±0.5 LSB), reference stability (±30ppm/°C), and power consumption (1.2mA typical at 3V). The device remains fully functional outside this range but may not meet datasheet limits.

Does MAX149ACPP require an external reference voltage?

No, the MAX149ACPP includes an internal 2.500V reference buffer with ±0.030V tolerance at +25°C and ±30ppm/°C temperature coefficient. Unlike the MAX148, the MAX149ACPP does not require an external reference - VREF pin delivers the regulated output, and REFADJ allows ±1.5% fine adjustment if needed. External reference use is optional and disabled by tying REFADJ to VDD.

How many analog input channels does MAX149ACPP support?

The MAX149ACPP supports eight analog input channels (CH0–CH7), configurable in either 8 single-ended mode (each referenced to COM) or 4 pseudo-differential pairs (CH0/CH1, CH2/CH3, CH4/CH5, CH6/CH7). Channel selection is controlled via the SEL2–SEL0 bits in the 8-bit serial control byte, with mode (SGL/DIF) and polarity (UNI/BIP) set independently per conversion.

What package type is used for MAX149ACPP?

The MAX149ACPP uses a 20-pin plastic dual in-line package (PDIP) with 0.3-inch body width and 0.1-inch pin pitch. This through-hole package is designated by the "PP" suffix and carries the "+" marking indicating RoHS-compliance and lead-free finish. It is pin-compatible with other MAX148/MAX149 variants in PDIP (e.g., MAX148ACPP+).

Can MAX149ACPP interface directly with a TMS320 DSP?

Yes, the MAX149ACPP supports direct connection to TMS320-family DSPs via its serial-strobe output (SSTRB), which pulses synchronously with conversion start/end. In internal clock mode, SSTRB goes low at conversion start and high at completion; in external clock mode, it pulses high for one SCLK period before MSB output. This eliminates need for polling or timer-based synchronization in DSP firmware.