Analog Devices Inc./Maxim Integrated MAX8211ESA+

Overview

MAX8211ESA+ from Analog Devices is a CMOS micropower voltage detector IC designed for microprocessor power-fail warning and programmable undervoltage/overvoltage monitoring. It features a 1.15V bandgap reference, open-drain n-channel output with 7mA current limiting, ±40mV threshold accuracy (±3.5%), and operates across 2.0V–16.5V supply range. It is used in battery-backup switching and power-supply fault monitoring circuits where low quiescent current (5µA) and noise-immune hysteresis are critical.

For engineers reviewing the MAX8211ESA+ datasheet, MAX8211ESA+ pinout, MAX8211ESA+ application, or MAX8211ESA+ equivalent, this page delivers verified technical context, real-world design meaning of key specs, validated pin functions, application-specific implementation guidance, and two confirmed alternative parts with precise functional and selection distinctions.

Technical Context

The MAX8211ESA+ integrates a precision 1.15V bandgap reference, comparator, and open-drain n-channel output stage that activates when THRESH voltage falls below the reference - enabling undervoltage detection. Its hysteresis output (HYST) provides positive feedback via external resistor networks to eliminate noise-induced chatter.

Unlike the MAX8212, the MAX8211ESA+ limits output sink current to 7mA (typ), allowing direct LED drive without series resistors. Threshold accuracy remains ±40mV over –40°C to +85°C, and input leakage at THRESH is ≤10nA (max), supporting high-impedance resistor dividers up to 10MΩ.

Key Specifications

Pinout & Package

MAX8211ESA+ is housed in an 8-pin SO (Small Outline) package (S8-2), RoHS-compliant, with gull-wing leads and standard 1.27mm pitch. Pin 1 is marked by a beveled corner or dot.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage monitoring applications.

Compared with TLV809E33DBZR and MAX6326UT29D3+, the MAX8211ESA+ uniquely supports fully programmable trip points across wide supply ranges, includes a dedicated hysteresis output for robust noise immunity, and maintains 7mA current-limited sinking - making it irreplaceable in adaptive, multi-rail, or battery-backed supervision systems.

Availability

MAX8211ESA+ is available at Aetrix Electronics and suitable for battery-backup switching, power-supply fault monitoring, and μP voltage monitoring applications requiring stable component supply, long-term lifecycle assurance, and industrial-grade temperature performance.

Supply support for MAX8211ESA+ 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

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The MAX8211ESA+ belongs to Analog Devices' precision voltage supervisor product line, engineered specifically for programmable, low-power, noise-immune power-rail monitoring in mission-critical embedded systems.

FAQ

What is the function of the HYST pin on the MAX8211ESA+?

The HYST pin on the MAX8211ESA+ is an open-drain p-channel output used to inject positive feedback into the external resistor divider network. When activated (i.e., pulled low), it raises the effective threshold voltage during rising input conditions, creating a controllable hysteresis band that prevents output oscillation due to noise on the THRESH node. This feature is essential for stable operation in electrically noisy environments and eliminates the need for external hysteresis circuitry.

Can the MAX8211ESA+ be used for overvoltage detection?

No - the MAX8211ESA+ is configured for undervoltage detection only: its output activates (pulls low) when the THRESH pin voltage falls *below* the internal 1.15V reference. For overvoltage detection, the MAX8212ESA+ variant must be used, as it triggers when THRESH exceeds 1.15V. Using MAX8211ESA+ in overvoltage configurations would invert logic behavior and fail to assert fault signals correctly.

What is the maximum output sink current capability of the MAX8211ESA+?

The MAX8211ESA+ provides a current-limited open-drain n-channel output with a typical sink current of 7mA and a hard limit of 30mA under any condition. This design allows direct driving of LEDs, optocouplers, or logic inputs without external current-limiting resistors - a key differentiator from non-current-limited alternatives like the MAX8212ESA+.

How does the MAX8211ESA+ compare to the legacy ICL8211?

The MAX8211ESA+ is a plug-in CMOS replacement for the bipolar ICL8211 in 8-pin SO packages. It improves upon the ICL8211 with 5µA vs. ~100µA quiescent current, ±40mV vs. ±100mV threshold accuracy, and 10mA HYST drive vs. 21µA - all while maintaining pin compatibility and identical resistor-divider programming methodology. These enhancements reduce system power, improve detection precision, and simplify hysteresis implementation.

What resistor values are recommended for setting a 4.5V trip point with the MAX8211ESA+?

To set a 4.5V trip point using the MAX8211ESA+, select R1 = 750kΩ (1%), then calculate R2 = R1 × (4.5V − 1.15V) / 1.15V ≈ 2.2MΩ (1%). For ~75mV hysteresis, add R3 = R2 × 75mV / (4.5V − 1.15V) ≈ 48.7kΩ (1%), connected between HYST and the THRESH node. These values match the reference design in Figure 5 of the MAX8211ESA+ datasheet and ensure worst-case tolerance margin.