Analog Devices Inc./Maxim Integrated MAX6706ZKA+

Overview

MAX6706ZKA+ from Maxim Integrated is an active-high push-pull microprocessor supervisory IC designed for single-supply voltage monitoring in embedded systems. It provides a guaranteed-reset output down to VCC = 1V, 140ms reset timeout delay, 0.62V power-fail comparator input, and independent watchdog timer with 1.6s timeout - all in an 8-pin SOT23 package for space-constrained industrial controllers and white goods.

For engineers reviewing the MAX6706ZKA+ datasheet, MAX6706ZKA+ pinout, MAX6706ZKA+ application, or MAX6706ZKA+ equivalent, this device delivers precise +2.32V (±3%) VCC reset threshold, manual reset input with 50kΩ internal pullup, open-drain PFO output, and WDI/WDO timing compatibility with µP NMI and reset logic - critical for reliable power-up sequencing and brownout recovery.

Technical Context

The MAX6706ZKA+ implements a dual-comparator architecture: one fixed-threshold monitor for VCC (2.32V nominal) and a separate 0.62V reference-based comparator for PFI, enabling early power-fail warning via PFO. Its active-high RESET output is synchronized to VCC rise/fall transitions with guaranteed validity down to 1V, eliminating external level-shifting in low-voltage systems.

Watchdog functionality operates independently of reset generation: WDO asserts low on 1.6s WDI timeout or undervoltage conditions, and deasserts immediately upon valid WDI edge or MR assertion - supporting fail-safe NMI-driven fault handling without latch-up risk in A-version logic.

Key Specifications

Pinout & Package

Package: 8-pin SOT23 (K8+2 outline), surface-mount, RoHS-compliant lead-free (+T suffix).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6706ZKA+, the MAX6706ZKA-T offers identical performance but lacks RoHS compliance, while MAX6705ZKA+ provides matching supervision features with inverted reset polarity - making MAX6706ZKA+ the optimal choice for new designs requiring both lead-free compliance and active-high reset drive capability.

Availability

MAX6706ZKA+ is available at Aetrix Electronics and suitable for industrial controllers, white goods, and intelligent instruments requiring stable component supply across extended temperature ranges (-40°C to +125°C) and long product lifecycles.

Supply support for MAX6706ZKA+ 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 industrial, computing, and communications applications, with expertise in power management and reliability-critical supervision.

The MAX6701–MAX6708 family was engineered specifically for µP power monitoring in harsh environments - delivering guaranteed reset validity, immune-to-transient operation, and integrated watchdog/PFI functions in minimal SOT23 footprint.

FAQ

What is the exact reset threshold voltage for MAX6706ZKA+ and how does it vary with temperature?

The MAX6706ZKA+ has a nominal VCC reset threshold of 2.32V, specified from 2.24V (min) to 2.40V (max) over the full -40°C to +125°C operating range. Its temperature coefficient is 60ppm/°C, meaning threshold drift is ≤±1.8mV over a 30°C ambient shift - sufficient for stable operation in automotive under-hood or industrial cabinet environments where MAX6706ZKA+ is deployed.

Does MAX6706ZKA+ support active-high reset output, and what are its drive capabilities?

Yes, MAX6706ZKA+ features an active-high push-pull RESET output. It sources ≥500µA at VCC ≥2.7V (VOH ≥0.8×VCC) and sinks ≥1.2mA at VCC ≥2.55V (VOL ≤0.3V), enabling direct drive of most µP reset inputs without external components. This distinguishes MAX6706ZKA+ from active-low variants like MAX6705ZKA+ and simplifies interface design.

How does the watchdog timer in MAX6706ZKA+ behave during power-up and reset events?

In MAX6706ZKA+, the watchdog timer is cleared whenever RESET is asserted - whether by VCC drop, MR activation, or watchdog timeout. It only begins counting after RESET deasserts, preventing false timeouts during boot. WDO asserts low on timeout but deasserts immediately upon next WDI edge, ensuring no dead time between fault detection and recovery - a key reliability feature of the A-version architecture used in MAX6706ZKA+.

Can MAX6706ZKA+ monitor voltages other than VCC, and how is that implemented?

Yes, MAX6706ZKA+ monitors secondary voltages via its PFI pin, which connects to an internal 0.62V reference. By applying a resistor divider from the target voltage (e.g., +12V motor supply) to PFI, users set custom trip points - for example, a 19:1 divider triggers PFO at 11.8V. PFO's open-drain output can then signal µP interrupt lines, enabling predictive shutdown before main supply failure - a function confirmed in MAX6706ZKA+'s datasheet Figure 10.

What is the minimum VCC required for MAX6706ZKA+ to guarantee valid RESET output operation?

MAX6706ZKA+ guarantees RESET output validity down to VCC = 1V - meaning the active-high RESET pin remains a defined logic high (≥0.8×VCC) or low (≤0.4V) even as supply collapses. This is critical for fail-safe operation in battery-powered or brownout-prone systems, and is explicitly tested and specified in the Electrical Characteristics table for MAX6706ZKA+, unlike many competitors that degrade below 1.8V.