Analog Devices Inc./Maxim Integrated MAX706PESA+

Overview

MAX706PESA+ from Maxim Integrated is an active-high reset, +3V microprocessor supervisory circuit with integrated watchdog timer, 1.25V power-fail comparator, and manual reset input. It monitors VCC for power-up, brownout, and power-down conditions; asserts RESET for ≥200ms; features 1.6s watchdog timeout; and operates over -40°C to +85°C in 8-pin SO package. Used in battery-powered portable instruments requiring reliable µP reset under fluctuating supply conditions.

For engineers reviewing the MAX706PESA+ datasheet, MAX706PESA+ pinout, MAX706PESA+ application, or MAX706PESA+ equivalent, this page delivers verified functional identity, exact reset threshold (2.63V), active-high RESET behavior, watchdog disable capability via WDI high-impedance state, and confirmed 8-pin SO (S8-2) packaging - all critical for BOM validation and schematic integration.

Technical Context

The MAX706PESA+ implements a precision voltage monitor with 2.63V reset threshold (±1.5% typical accuracy) and 20mV hysteresis, guaranteeing RESET assertion down to VCC = 1V. Its internal 1.6s watchdog timer resets on WDI edge transitions and disables automatically when WDI is left open or driven high-impedance (<600nA leakage), distinguishing it from non-A variants.

A dedicated 1.25V reference feeds the PFI comparator for independent power-fail or low-battery detection, while the debounced TTL/CMOS-compatible MR input supports pushbutton or logic-triggered reset with 500ns minimum pulse width at VCC = 3V. RESET output is strictly active-high with guaranteed VOH ≥ 0.8×VCC (ISOURCE = 500µA) and VOL ≤ 0.3V (ISINK = 1.2mA).

Key Specifications

Pinout & Package

MAX706PESA+ is housed in an 8-pin SOIC package (S8-2), 3.9mm × 4.9mm body, 1.27mm pitch, lead-free compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX706RCSA+, MAX706PESA+ eliminates external level-shifting for active-high µP reset pins; compared with TPS3808G125DBVR, it adds watchdog supervision at the cost of higher quiescent current - a trade-off justified in systems requiring autonomous firmware recovery.

Availability

MAX706PESA+ is available at Aetrix Electronics and suitable for battery-powered instrumentation, industrial controllers, medical diagnostics, and embedded gateways requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX706PESA+ 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 management, sensing, and interface applications in industrial, automotive, and communications markets.

The MAX706 family delivers low-cost, highly integrated µP supervisory functions - including reset generation, watchdog monitoring, and power-fail detection - specifically optimized for +3V/+3.3V embedded systems with stringent reliability and footprint requirements.

FAQ

What is the reset threshold voltage of the MAX706PESA+?

The MAX706PESA+ has a guaranteed reset threshold of 2.63V (VCC falling), with ±1.5% typical tolerance and 20mV hysteresis. This value is factory-trimmed and specified over the full -40°C to +85°C operating range. The threshold ensures reliable reset assertion before most +3.3V µPs exit their valid operating window, and MAX706PESA+ guarantees RESET remains asserted down to VCC = 1V for fail-safe behavior during deep brownout.

Does the MAX706PESA+ have a watchdog timer, and how is it configured?

Yes, the MAX706PESA+ includes a 1.6s watchdog timer with WDI input and WDO output. A rising or falling edge on WDI resets the timer; absence of edges for >1.6s asserts WDO low. Crucially, the watchdog function disables automatically when WDI is left open or driven into high-impedance (leakage <600nA), enabling safe deactivation during µP sleep modes without external circuitry - a key differentiator from non-A variants like MAX706R.

What is the function of the PFI and PFO pins on the MAX706PESA+?

PFI is the power-fail comparator input, internally referenced to a precise 1.25V bandgap. When external voltage at PFI falls below 1.25V, PFO (active-low) asserts to signal impending supply failure. This allows flexible use cases: monitoring unregulated rails for early warning, detecting low battery via resistor divider, or triggering µP interrupts. PFO sinks current when active and requires no external pull-up due to its open-drain structure.

Is the RESET output of the MAX706PESA+ active-high or active-low?

The RESET output of the MAX706PESA+ is strictly active-high, as indicated by the "P" suffix in the part number. It drives high during power-up, brownout, or manual reset, and remains high for ≥200ms after fault clearance. This eliminates the need for external inverters when interfacing with µPs that require high-level reset assertion - unlike MAX706R (active-low) or MAX708R (dual active-high/low outputs).

What package type and temperature range does the MAX706PESA+ use?

The MAX706PESA+ is supplied in an 8-pin SOIC package (S8-2 footprint, 3.9mm × 4.9mm), lead-free and RoHS-compliant. It is fully specified for operation from -40°C to +85°C, making it suitable for industrial and extended-temperature embedded applications. The "E" in the suffix denotes the extended temperature grade, and "SA" confirms the SOIC packaging - distinct from PDIP ("PA") or µMAX ("UA") variants.