Analog Devices Inc./Maxim Integrated MAX187BCWE+T

Overview

MAX187BCWE+T from Maxim Integrated is a 12-bit successive-approximation analog-to-digital converter (ADC) with integrated 4.096V buffered reference, single +5V supply operation, 75ksps throughput rate, ±½ LSB integral nonlinearity (A-grade), and 3-wire SPI/QSPI/MICROWIRE-compatible serial interface - used in portable data loggers and isolated sensor interfaces where low power and small footprint are critical.

For engineers reviewing the MAX187BCWE+T datasheet, MAX187BCWE+T pinout, MAX187BCWE+T application, or MAX187BCWE+T equivalent, this page delivers verified electrical specs, package mapping to 16-pin wide SO, functional pin roles, real-world use cases, and two validated alternative ADCs for unipolar 0–4.096V measurement systems requiring <10 µA shutdown current and internal reference capability.

Technical Context

The MAX187BCWE+T implements an 8.5-clock-cycle SAR architecture with on-chip track/hold (1.5 µs acquisition time), internal bandgap reference trimmed to 4.096V ±0.5%, and unipolar input range referenced to REF. It uses no external hold capacitor and achieves 70dB SINAD at 10kHz input with 80dB SFDR.

Its serial interface operates with SCLK up to 5MHz, requires only CS, SCLK, and DOUT lines, and outputs MSB-first data preceded by a high EOC bit - compatible with SPI mode 0 (CPOL=0, CPHA=0) and QSPI without additional framing logic.

Key Specifications

Pinout & Package

MAX187BCWE+T is housed in a 16-pin wide SO (SOIC-W) package with exposed pad (not electrically connected), 7.5 mm × 10.3 mm body, 1.27 mm pitch, and moisture sensitivity level 3. Pin functions are validated per Maxim's official pin description table and functional diagram.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7822U and MAX11131AUT+T, the MAX187BCWE+T uniquely combines 5V-native operation, three-level SHDN control for flexible reference selection, and broad serial protocol compatibility - making it optimal for retrofitting legacy 5V microcontroller systems with minimal layout change.

Availability

MAX187BCWE+T is available at Aetrix Electronics and suitable for portable data logging, remote DSP, isolated data acquisition, and high-accuracy process control requiring stable component supply across industrial temperature ranges (–40°C to +85°C).

Supply support for MAX187BCWE+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) is a semiconductor company specializing in precision analog, mixed-signal, and power management ICs for industrial, medical, and communications applications.

The MAX187 series was designed specifically for low-power, space-constrained 12-bit data acquisition systems requiring integrated reference and simple 3-wire interfacing - targeting portable instrumentation and distributed sensor networks.

FAQ

What is the reference voltage accuracy of the MAX187BCWE+T over temperature?

The MAX187BCWE+T features an internal 4.096V buffered reference with ±0.5% initial accuracy at +25°C and ±0.076V (±1.85%) total variation over the full –40°C to +85°C operating range (MAX187BE grade). This corresponds to ±30 ppm/°C typical tempco, enabling stable 1 mV/LSB scaling without recalibration in most field-deployed systems.

Can the MAX187BCWE+T operate with an external reference while retaining its internal reference functionality?

No - the MAX187BCWE+T uses SHDN pin state to select reference mode: pulling SHDN high enables the internal 4.096V reference, while floating SHDN disables it and allows external reference application at the REF pin. Both modes cannot be active simultaneously; the internal reference is physically disconnected when SHDN is floating.

What is the minimum acquisition time required between consecutive conversions on the MAX187BCWE+T?

The MAX187BCWE+T requires a minimum 1.5 µs track/hold acquisition time (tACQ) after CS goes high before the next CS falling edge initiates a new conversion. This interval ensures full settling of the internal hold capacitor; violating it degrades AC performance and may cause missing codes, especially with high-source-impedance sensors.

Does the MAX187BCWE+T support daisy-chained SPI configurations?

No - the MAX187BCWE+T does not support daisy-chaining. Its serial interface uses a dedicated DOUT line per device and requires individual CS control. Multiple MAX187BCWE+T units must be connected in parallel with separate CS lines driven by GPIO or decoder logic; shared SCLK and DOUT lines are permissible only if CS is asserted one-at-a-time.

How does the MAX187BCWE+T handle input overvoltage conditions on the AIN pin?

The MAX187BCWE+T includes internal clamping diodes on AIN, allowing safe operation with inputs from GND – 0.3V to VDD + 0.3V. However, for accurate conversion near full scale, AIN must remain within GND to VDD + 50mV. Exceeding this range by more than 50mV requires limiting input current to ≤2mA to prevent accuracy degradation or long-term reliability risk.