Analog Devices Inc./Maxim Integrated MAX1228BCEP+T

Overview

MAX1228BCEP+T from Maxim Integrated is a 12-bit, 300ksps serial analog-to-digital converter with integrated temperature sensor (±1.2°C error over -40°C to +85°C), on-chip 16-entry FIFO, internal 4.096V reference, and SPI/QSPI/MICROWIRE-compatible 3-wire interface. It supports 12 single-ended or 6 true differential input channels in unipolar/bipolar modes and operates from a single +5V supply. It is used in industrial data-acquisition systems requiring channel scanning, internal averaging, and low-power system supervision.

For engineers reviewing the MAX1228BCEP+T datasheet, MAX1228BCEP+T pinout, MAX1228BCEP+T application, or MAX1228BCEP+T equivalent, key selection considerations include its 20-pin QSOP package, internal temperature sensing capability, FIFO-buffered scan mode operation, ±1 LSB INL/DNL accuracy, and compatibility with microprocessor-controlled acquisition sequences using external clocking up to 10MHz.

Technical Context

The MAX1228BCEP+T implements a fully differential successive-approximation register (SAR) ADC architecture with integrated track-and-hold, supporting both single-ended and true differential inputs. Its internal oscillator enables autonomous conversion timing in clock modes 00, 01, and 10, while clock mode 11 supports externally timed acquisitions at up to 300ksps using SCLK.

It features configurable input multiplexing across 12 analog inputs (AIN0–AIN11), with REF-/AIN10 and CNVST/AIN11 sharing pins for flexible reference and conversion-start routing. The device uses an internal 4.096V reference (±20ppm/°C TC) or accepts external differential references, and all conversions - including temperature measurements - are digitized to 12-bit resolution with no missing codes over temperature.

Key Specifications

Pinout & Package

MAX1228BCEP+T is housed in a 20-pin QSOP package (5.3mm × 10.2mm, 0.65mm pitch) with gull-wing leads and RoHS-compliant matte-tin plating. Pin 1 is marked by a beveled corner; the package is moisture-sensitive level 3 per J-STD-020.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multichannel, temperature-integrated ADC applications.

Compared with ADS7822U and AD7490BRUZ, the MAX1228BCEP+T uniquely integrates temperature sensing, FIFO buffering, and flexible clock-mode control in a 20-pin QSOP - enabling compact, self-contained data-acquisition subsystems without external timing or buffering logic.

Availability

MAX1228BCEP+T is available at Aetrix Electronics and suitable for industrial process monitoring, portable medical instrumentation, environmental data logging, and automated test equipment requiring stable component supply and long-term production continuity.

Supply support for MAX1228BCEP+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 industrial, medical, and communications applications.

The MAX1228BCEP+T belongs to Maxim's high-accuracy, low-power SAR ADC product line, engineered for embedded data-acquisition systems needing integrated diagnostics, multichannel flexibility, and minimal external component count.

FAQ

What is the operating temperature range for the MAX1228BCEP+T?

The MAX1228BCEP+T is specified for commercial-grade operation from 0°C to +70°C. This is indicated by the "C" suffix in the part number and confirmed in the Ordering Information table. It is not rated for extended industrial (-40°C to +85°C) operation - that grade is designated by the "E" suffix (e.g., MAX1228BEEP+). The internal temperature sensor remains functional across this 0°C to +70°C range with ±1.2°C accuracy.

Does the MAX1228BCEP+T require an external reference voltage?

No, the MAX1228BCEP+T does not require an external reference voltage. It includes a factory-trimmed internal 4.096V reference with ±20ppm/°C temperature coefficient, which is used by default for both analog-to-digital conversion and temperature sensing. An external differential reference can be applied via REF+ and REF-/AIN10 pins only if higher precision or custom scaling is needed - but doing so disables the internal reference and temperature sensor functionality.

How many analog input channels does the MAX1228BCEP+T support?

The MAX1228BCEP+T supports 12 single-ended analog input channels (AIN0 through AIN11) or 6 true differential input pairs (e.g., AIN0/AIN1, AIN2/AIN3, etc.). This is fixed by the device's silicon configuration and matches the "1228" family designation. Pins 12 (CNVST/AIN11) and 13 (REF-/AIN10) are multifunctional - they serve as analog inputs only when not configured as control signals in the setup register.

Can the MAX1228BCEP+T perform automatic channel scanning?

Yes, the MAX1228BCEP+T supports automatic channel scanning via its internal FIFO and programmable scan modes. Writing to the NSCAN1/NSCAN0 bits in the averaging register configures the number of channels (1–16) to be scanned sequentially. In clock modes 00 or 10, a single write to the conversion register initiates a full scan; results are stored in the 16-deep FIFO and read out via SPI without further host intervention until the FIFO is emptied.

What package type is used for the MAX1228BCEP+T?

The MAX1228BCEP+T uses a 20-pin QSOP (Quad Small Outline Package) with gull-wing leads, measuring 5.3mm × 10.2mm and featuring a 0.65mm lead pitch. The "P" in the suffix denotes QSOP packaging, distinct from the "N" (24-pin QSOP) or "Q" (28-pin TQFN) variants used for other members of the MAX1226/MAX1228/MAX1230 family. It is RoHS-compliant and lead-free.