Analog Devices Inc./Maxim Integrated MAX1090BEEI

Overview

MAX1090BEEI from Maxim Integrated is a 10-bit successive-approximation analog-to-digital converter (SAR ADC) with integrated +2.5V reference, byte-wide parallel (8+2) interface, and software-configurable 8-channel single-ended or 4-channel pseudo-differential input multiplexer. It operates from a single +5V analog supply and supports digital logic levels from +2.7V to +5.5V via VLOGIC. Designed for battery-powered data acquisition, it delivers 400ksps sampling at 2.5mA supply current and features 2µs wake-up from shutdown.

For engineers reviewing the MAX1090BEEI datasheet, MAX1090BEEI pinout, MAX1090BEEI application, or MAX1090BEEI equivalent, key selection criteria include its ±1 LSB INL over –40°C to +85°C, internal track-and-hold with 6MHz full-power bandwidth, tri-state INT output, and QSOP-28 package compatibility with industrial temperature-grade variants of the MAX1090 family.

Technical Context

The MAX1090BEEI implements a charge-redistribution SAR architecture with an internal 10-bit capacitive DAC and a track-and-hold stage featuring 350kHz full-linear and 6MHz full-power bandwidth. Its control logic accepts an 8-bit configuration byte defining channel address (A2–A0), unipolar/bipolar mode, single-ended/pseudo-differential mode, acquisition mode (internal/external), and power-down state.

Conversion timing is clock-dependent: 13 cycles per conversion, supporting external clocks from 100kHz to 7.6MHz or internal clock mode (3.6µs conversion time). The HBEN pin enables high-byte (D8/D9) or low-byte (D0–D7) multiplexing on the parallel bus, and INT asserts low upon result readiness-tri-stating when CS goes high.

Key Specifications

Pinout & Package

MAX1090BEEI is housed in a 28-pin QSOP package with exposed pad (not thermally enhanced), footprint compatible with industry-standard 28QSOP land patterns. Pin 1 is marked by a dot; pin numbering follows standard counter-clockwise orientation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX1090ACEI, the MAX1090BEEI trades ±0.5 LSB INL for guaranteed –40°C to +85°C performance and broader industrial qualification; compared with ADS7822U, it provides higher resolution, parallel throughput, and reference integration at the cost of larger package and higher pin count.

Availability

MAX1090BEEI is available at Aetrix Electronics and suitable for industrial process monitoring, portable medical instrumentation, and energy metering applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX1090BEEI 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, automotive, and communications markets.

The MAX1090 series belongs to Maxim's precision data acquisition product line, designed specifically for low-power, multi-channel 10-bit SAR conversion in space-constrained, battery-operated, or thermally demanding systems.

FAQ

What is the operating temperature range of the MAX1090BEEI?

The MAX1090BEEI is rated for –40°C to +85°C operation, validated across this full industrial temperature range for parameters including INL (±1 LSB), DNL (±1 LSB), and reference voltage stability (±20ppm/°C). This makes the MAX1090BEEI suitable for deployment in harsh environments such as factory automation cabinets or outdoor energy meters where ambient extremes are expected.

Does the MAX1090BEEI require an external clock to operate?

No-the MAX1090BEEI supports both internal and external clock modes. In internal clock mode (configured via control byte bits D7/D6), it uses an on-chip oscillator delivering a fixed 3.6µs conversion time. External clock mode (D7=D6=1) accepts 100kHz–7.6MHz TTL/CMOS signals, enabling precise timing control and synchronization with system clocks. The CLK pin must be tied to VDD or GND in internal mode to prevent floating.

How does the HBEN pin affect data readout on the MAX1090BEEI?

The HBEN (High-Byte Enable) pin determines how the 10-bit conversion result is presented on the 8-bit data bus: when HBEN = 0, D0–D7 carry the 8 LSBs; when HBEN = 1, D0 carries D8 and D1 carries D9, allowing access to the two MSBs. This multiplexing avoids requiring a 10-bit bus and enables compatibility with standard 8-bit microprocessor data paths while preserving full 10-bit resolution.

Can the MAX1090BEEI interface directly with a 3.3V microcontroller?

Yes-the MAX1090BEEI's VLOGIC pin accepts +2.7V to +5.5V, so connecting VLOGIC to 3.3V configures all digital outputs (D0–D9, INT, RD, WR, CS) to 3.3V logic levels. Inputs remain 5V-tolerant, allowing direct connection to 3.3V µPs without level shifters. The analog supply (VDD) remains at +5V to maintain full dynamic range and reference accuracy.

What is the purpose of the COM pin on the MAX1090BEEI?

The COM (Common) pin serves as the analog ground reference for single-ended measurements and the negative input reference in pseudo-differential mode. In single-ended operation, it defines the zero-code voltage; in pseudo-differential mode, it establishes the common-mode point for paired channels (e.g., CH0/CH1). Stability of COM to ±0.5 LSB during conversion is mandatory-achieved via low-impedance routing and local decoupling-to prevent INL degradation.