Analog Devices Inc./Maxim Integrated MAX147ACAP+T

Overview

MAX147ACAP+T from Maxim Integrated is a 12-bit, 8-channel serial analog-to-digital converter (ADC) with software-configurable unipolar/bipolar and single-ended/differential inputs, 133ksps conversion rate, ±0.5 LSB INL, and +2.7V to +5.25V single-supply operation - used in portable data loggers and battery-powered medical instruments.

For engineers reviewing the MAX147ACAP+T datasheet, MAX147ACAP+T pinout, MAX147ACAP+T application, or MAX147ACAP+T equivalent, this page delivers verified electrical specs, real-world timing behavior, package-confirmed pin functions, and validated alternative ADCs for low-power, multi-channel sampling systems requiring external reference flexibility and SPI/QSPI/MICROWIRE compatibility.

Technical Context

The MAX147ACAP+T implements successive-approximation architecture with integrated track/hold, supporting both internal clock (for autonomous conversion control) and external serial clock (for precise timing synchronization). Its analog front-end enables pseudo-differential sampling via CH0–CH7 multiplexer pairs (e.g., CH0/CH1), with COM pin defining zero-code reference in single-ended mode.

It features a reference-buffer amplifier with ±1.5% REFADJ adjustment range and requires an external 2.5V reference applied at VREF - unlike the MAX146 which integrates an internal 2.5V reference. Power management includes hardware SHDN pin and software-selectable full/fast power-down modes, enabling sub-60µA supply current at reduced sampling rates.

Key Specifications

Pinout & Package

MAX147ACAP+T is housed in a 20-pin SSOP (Shrink Small Outline Package) with 0.65mm lead pitch, RoHS-compliant, and rated for 0°C to +70°C industrial operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7822U and MAX11131ETE+, the MAX147ACAP+T uniquely balances wide supply range (+2.7V to +5.25V), external reference control, and 133ksps performance - making it optimal for portable, multi-voltage, and precision-calibrated systems where reference sourcing and power efficiency are co-priorities.

Availability

MAX147ACAP+T is available at Aetrix Electronics and suitable for portable data logging, battery-powered medical instruments, and industrial process monitoring requiring stable component supply and long-term lifecycle assurance.

Supply support for MAX147ACAP+T 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) designs precision analog, mixed-signal, and power management ICs for demanding industrial, medical, and communications applications.

The MAX146/MAX147 product line targets low-power, multi-channel data acquisition systems requiring flexible input configuration, serial interface simplicity, and robust performance across extended temperature and supply ranges.

FAQ

What is the reference configuration requirement for MAX147ACAP+T?

The MAX147ACAP+T requires an external 2.5V reference applied to the VREF pin. Unlike the MAX146, it does not include an internal reference. To disable the internal reference buffer, REFADJ must be tied to VDD. This configuration ensures accurate, system-level reference control and avoids reliance on the device's internal buffer, which is absent in the MAX147 family.

Does MAX147ACAP+T support differential input mode, and how is it configured?

Yes, MAX147ACAP+T supports pseudo-differential input mode using four channel pairs: CH0/CH1, CH2/CH3, CH4/CH5, and CH6/CH7. Configuration is done via the 8-bit control byte written to DIN - setting SGL/DIF = 0 and selecting appropriate SEL2–SEL0 bits per Table 3 in the datasheet. The negative input (IN−) must remain stable within ±0.5 LSB relative to AGND during conversion.

What is the maximum sampling rate achievable with MAX147ACAP+T, and what limits it?

The MAX147ACAP+T achieves a maximum conversion rate of 133ksps using a 2MHz external serial clock with 15 clock cycles per conversion. This rate is limited by the internal successive-approximation DAC settling time and track/hold acquisition window (tACQ = 1.5µs minimum). Higher clock frequencies do not increase throughput due to fixed internal timing constraints.

How does the SHDN pin function on MAX147ACAP+T, and what are its three states?

The SHDN pin on MAX147ACAP+T provides three distinct operating states: pulled low → full shutdown (1µA supply current); left floating → external compensation mode for REFADJ (enabling use of low-ESR ceramic caps); pulled high → internal compensation mode. This three-level control allows precise power management and reference stability tuning without additional external components.

Can MAX147ACAP+T interface directly with a TMS320-series DSP, and what signal enables that?

Yes, MAX147ACAP+T interfaces directly with TMS320-family DSPs using its SSTRB (serial strobe) output. SSTRB pulses high for one SCLK period before the MSB of the conversion result is shifted out on DOUT - providing a hardware-synchronized timing signal that aligns with the DSP's external interrupt or DMA trigger, eliminating software polling latency in real-time control loops.