Analog Devices Inc./Maxim Integrated MAX1090BEEI+

Overview

MAX1090BEEI+ from Maxim Integrated is a 10-bit successive-approximation ADC with integrated +2.5V reference, 8-channel single-ended / 4-channel pseudo-differential analog input multiplexer, byte-wide parallel (8+2) interface, and software-configurable unipolar/bipolar operation. It operates from a single +5V analog supply and supports digital logic levels from +2.7V to +5.5V via VLOGIC, targeting battery-powered data-acquisition systems requiring low power and compact size.

For engineers reviewing the MAX1090BEEI+ datasheet, MAX1090BEEI+ pinout, MAX1090BEEI+ application, or MAX1090BEEI+ equivalent, key selection criteria include its -40°C to +85°C industrial temperature grade, ±1 LSB INL, 400ksps max sampling rate with 2.5mA active current, and QSOP-28 package compatibility with system-level timing, power-down sequencing, and analog input channel routing constraints.

Technical Context

The MAX1090BEEI+ implements a charge-redistribution SAR architecture with an internal track-and-hold stage offering 6MHz full-power bandwidth and 350kHz full-linear bandwidth. Its control byte (D7–D0) configures acquisition mode (internal/external), clock source (internal/external), unipolar/bipolar range, and channel selection - enabling flexible integration into µP-based systems without external timing components.

It features dual power-down modes reducing supply current to <2µA in shutdown, fast wake-up (2µs), and tri-state INT output synchronized to CS. The VLOGIC pin decouples digital I/O voltage from analog supply, supporting mixed-voltage system interfacing while maintaining ±0.5 LSB DNL and no missing codes over temperature.

Key Specifications

Pinout & Package

MAX1090BEEI+ is housed in a 28-pin QSOP package (5.3mm × 10.2mm, 0.65mm pitch), optimized for high-density PCB layouts in industrial and portable instrumentation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX1090ACEI+, the MAX1090BEEI+ trades ±0.5 LSB INL for guaranteed -40°C to +85°C operation and broader supply tolerance; versus ADS7822U, it delivers 2-bit higher resolution, parallel interface speed, integrated reference, and true industrial temperature capability - making it irreplaceable in ruggedized embedded systems.

Availability

MAX1090BEEI+ is available at Aetrix Electronics and suitable for industrial control systems, portable medical devices, 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) designs precision analog, mixed-signal, and power management ICs for demanding industrial, automotive, and communications applications.

The MAX1090BEEI+ belongs to Maxim's low-power, high-accuracy data-conversion product line, engineered specifically for space- and power-constrained systems needing integrated reference, flexible input configuration, and robust industrial-grade operation.

FAQ

What is the operating temperature range of the MAX1090BEEI+?

The MAX1090BEEI+ is rated for industrial operation from -40°C to +85°C. This specification is confirmed in the Ordering Information table of the datasheet, where the "E" suffix denotes the extended temperature grade. Unlike the "C" grade (0°C to +70°C), the MAX1090BEEI+ maintains ±1 LSB INL and full 400ksps performance across this full range, making it suitable for deployment in harsh environments such as factory floors or outdoor metering equipment.

Does the MAX1090BEEI+ require an external clock to operate?

No, the MAX1090BEEI+ supports both internal and external clock modes. When configured for internal clock mode (D7=1, D6=0 in the control byte), the device uses an on-chip oscillator - eliminating the need for an external clock source. In that mode, the CLK pin must be tied to VDD or GND to prevent floating. External clock mode (D7=D6=1) accepts 100kHz–7.6MHz TTL/CMOS signals, providing precise aperture control for undersampling applications.

How does the HBEN pin function on the MAX1090BEEI+?

The HBEN (High Byte Enable) pin on the MAX1090BEEI+ controls multiplexing of the 10-bit conversion result onto the 8-bit data bus. When HBEN = 1, D0/D8 and D1/D9 carry the two most significant bits (MSBs); when HBEN = 0, D0–D7 carry the eight least significant bits (LSBs). This allows full 10-bit reads in two consecutive cycles without requiring a 10-bit wide bus, simplifying interface to standard 8-bit microcontrollers.

Can the MAX1090BEEI+ interface directly with a 3.3V microcontroller?

Yes, the MAX1090BEEI+ can interface directly with a 3.3V microcontroller using its VLOGIC pin. By connecting VLOGIC to +3.3V, all digital outputs (D7–D0, INT, RD, WR, CS, HBEN) are referenced to that voltage, ensuring compatible logic thresholds and eliminating external level shifters. The datasheet specifies VLOGIC operation from +2.7V to +5.5V, and output drive strength remains fully specified at 3.3V with VOH ≥ 2.8V and VOL ≤ 0.4V under load.

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

The COM (Common) pin on the MAX1090BEEI+ serves as the zero-reference point for single-ended analog inputs and the negative input reference in pseudo-differential mode. In single-ended operation, all channels (CH0–CH7) are measured relative to COM, which must be held stable to ±0.5 LSB during conversion. In pseudo-differential mode, COM is not used; instead, pairs like CH0/CH1 form differential inputs. The COM pin must be decoupled with low-ESR capacitance if driven externally.