Analog Devices Inc./Maxim Integrated MAX706ATEUA+

Overview

MAX706ATEUA+ from Maxim Integrated is an active-low microprocessor supervisory circuit in 8-pin µMAX package, providing reset generation (200ms delay), watchdog timer (1.6s timeout), 1.25V power-fail comparator input, and debounced manual-reset input. It monitors +3V/+3.3V supplies with 3.08V reset threshold and operates over –40°C to +85°C for battery-powered instrumentation and embedded controllers.

For engineers reviewing the MAX706ATEUA+ datasheet, MAX706ATEUA+ pinout, MAX706ATEUA+ application, or MAX706ATEUA+ equivalent, this page delivers verified electrical parameters, validated pin functions, confirmed operating conditions, and real-world use cases - all specific to the MAX706ATEUA+ variant with 3.08V reset threshold and industrial temperature range.

Technical Context

The MAX706ATEUA+ implements a precision voltage-monitoring architecture with internal 3.08V reset threshold (±1.5% tolerance), guaranteed RESET assertion down to VCC = 1V, and integrated 1.25V reference for external PFI monitoring. Its watchdog timer resets on WDI edge transitions and disables automatically when WDI is left open or driven high-impedance (<600nA leakage).

Reset pulse width is fixed at 200ms (min 90ms, max 300ms over temperature), and the active-low RESET output drives CMOS/TTL loads with VOL ≤ 0.3V at 1.2mA sink current. The device draws only 100µA quiescent current at VCC = 3.3V and supports supply voltages from 3.15V to 5.5V.

Key Specifications

Pinout & Package

MAX706ATEUA+ uses the 8-pin µMAX package (U8-1), measuring 3mm × 3mm with exposed pad for thermal performance. Pin 1 is marked by dot; pin numbering follows standard SO/µMAX counterclockwise convention.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor supervisory applications.

Compared with MAX706TEUA+, MAX706ATEUA+ offers identical functionality and is its direct replacement in new designs; compared with TPS3808G33DBVR, MAX706ATEUA+ provides integrated watchdog and PFI capability at higher quiescent current but broader system protection scope.

Availability

MAX706ATEUA+ is available at Aetrix Electronics and suitable for battery-powered equipment, industrial microcontroller controllers, and embedded computing systems requiring stable component supply, long-term lifecycle support, and guaranteed industrial-temperature operation.

Supply support for MAX706ATEUA+ 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 and mixed-signal ICs for power, sensing, and interface applications in industrial, automotive, and communications markets.

The MAX706 family targets cost-sensitive, space-constrained µP systems needing reliable power monitoring and fault recovery - optimized for +3V/+3.3V domains with minimal external components.

FAQ

What is the reset threshold voltage for MAX706ATEUA+?

The MAX706ATEUA+ has a factory-trimmed reset threshold of 3.08V (VCC falling), with ±1.5% accuracy over temperature. This value is specified in the Electrical Characteristics table under "Reset Threshold (VCC Falling)" for MAX70_T/MAX706AT variants. It ensures reliable reset assertion just before +3.3V systems enter brownout, and is distinct from the 2.63V or 2.93V thresholds used in other MAX706 suffix variants.

Does MAX706ATEUA+ include a watchdog timer, and how is it enabled?

Yes, MAX706ATEUA+ includes a 1.6s watchdog timer that asserts WDO low if no edge transition occurs on WDI within the timeout period. The timer is always active unless WDI is left open or driven into high-impedance state with leakage <600nA - a feature unique to the MAX706AT series. No external enable signal is required; toggling WDI resets the timer, and asserting MR or dropping VCC below threshold also resets it.

Can MAX706ATEUA+ monitor a secondary power supply like +12V or negative voltage?

Yes, MAX706ATEUA+ can monitor secondary supplies using its PFI input. For +12V, connect PFI to a resistive divider that outputs 1.25V when the +12V rail reaches the desired trip point (e.g., 11V). For negative supplies, use the Figure 8 circuit where PFI is referenced to VCC and the comparator inverts the sense - PFO goes high when the negative rail drops. Accuracy depends on resistor tolerance and PFI input current (±25nA max).

What is the minimum VCC level at which MAX706ATEUA+ guarantees RESET assertion?

MAX706ATEUA+ guarantees RESET remains asserted (low) down to VCC = 1.0V at TA = –40°C to +85°C. Below 1V, the RESET output becomes high-impedance. This behavior is documented in the "RESET and RESET Outputs" section and ensures fail-safe reset hold during deep brownout - critical for preventing µP execution errors in low-voltage transients.

Is MAX706ATEUA+ pin-compatible with other MAX706 variants in the µMAX package?

Yes, all MAX706P/R/S/T, MAX706AP/AR/AS/AT, and MAX708R/S/T variants share identical 8-pin µMAX (U8-1) pinouts and mechanical footprint. However, function differs: MAX706ATEUA+ provides active-low RESET and WDO, while MAX706P variants provide active-high RESET and lack WDI/WDO. Always verify reset polarity and feature set - pin compatibility does not imply functional interchangeability.