Analog Devices Inc./Maxim Integrated MAX706TEPA+

Overview

MAX706TEPA+ from Maxim Integrated is an active-low microprocessor supervisory circuit designed for +3V to +5V systems, providing power-on reset, watchdog timeout (1.6s), 1.25V power-fail detection, and debounced manual reset. It asserts RESET when VCC falls below 3.08V or MR is pulled low, with guaranteed reset assertion down to VCC = 1V. Used in battery-powered portable instruments and industrial controllers requiring reliable brownout protection.

For engineers reviewing the MAX706TEPA+ datasheet, MAX706TEPA+ pinout, MAX706TEPA+ application, or MAX706TEPA+ equivalent, key selection considerations include its 3.08V reset threshold, -40°C to +85°C operating range, PDIP-8 package, active-low RESET output, and integrated watchdog timer with WDI disable capability.

Technical Context

The MAX706TEPA+ implements a precision voltage monitor with 3.08V reset threshold (±1.5% typical accuracy) and 20mV hysteresis, ensuring stable reset assertion during supply transients. Its internal watchdog timer resets on any WDI edge and times out after 1.6s (±40%), with automatic disable when WDI is left open or driven high-impedance (<600nA leakage).

A dedicated 1.25V comparator monitors PFI for power-fail or low-battery warning, while the MR input accepts TTL/CMOS-compatible pulses as short as 150ns at VCC = 5V. RESET remains asserted for 200ms after VCC exceeds threshold or MR release, with guaranteed logic-level drive down to VCC = 1V.

Key Specifications

Pinout & Package

MAX706TEPA+ is housed in an 8-pin plastic DIP (PDIP) package (package code P8-1), through-hole mountable with 0.3" width and standard 0.1" pin pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX706TEPA+, MAX706SEPA+ triggers reset 150mV earlier-critical for systems with marginal LDO headroom-while MAX706REPA+ provides 450mV additional dropout margin, making it preferable for noisy industrial rails where 3.08V may cause premature reset.

Availability

MAX706TEPA+ is available at Aetrix Electronics and suitable for battery-powered equipment, industrial controllers, and embedded computing applications requiring stable component supply across extended temperature ranges.

Supply support for MAX706TEPA+ 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 connectivity applications.

The MAX706 family delivers cost-effective, integrated µP supervision for +3V systems, targeting portable, industrial, and computing applications where reliability under brownout and watchdog coverage are essential.

FAQ

What is the reset threshold voltage for MAX706TEPA+?

The MAX706TEPA+ has a fixed reset threshold of 3.08V ±1.5%, specified for VCC falling conditions. This value is laser-trimmed during production and applies across the full -40°C to +85°C operating range. The threshold ensures reliable reset assertion before a +3.3V supply falls below the minimum operating voltage of most 3.3V microprocessors. MAX706TEPA+ does not support adjustable reset thresholds.

Does MAX706TEPA+ include a watchdog timer function?

Yes, MAX706TEPA+ integrates a watchdog timer with a nominal timeout period of 1.6s ±40%. The timer resets on any rising or falling edge at the WDI pin and asserts the WDO output low if no transition occurs within the timeout window. Unlike some variants, MAX706TEPA+ supports WDI disable-leaving WDI open or connecting it to a high-impedance tri-state output automatically disables the watchdog function.

What package type is used for MAX706TEPA+?

MAX706TEPA+ is supplied in an 8-pin plastic dual in-line package (PDIP) with 0.3" body width and standard 0.1" pin spacing (package code P8-1). This through-hole package supports wave soldering and prototyping on breadboards or perfboards. It is lead-free compliant and rated for operation from -40°C to +85°C.

Can MAX706TEPA+ monitor voltages other than VCC?

Yes, MAX706TEPA+ includes a dedicated PFI (Power-Fail Input) pin with an internal 1.25V reference comparator. By connecting PFI to a resistive divider from an unregulated supply (e.g., +12V or -5V), users can configure early-warning power-fail detection at custom thresholds. The PFO output asserts low when the divided voltage falls below 1.25V, enabling interrupts or secondary reset generation independent of VCC monitoring.

How does the manual reset (MR) input behave on MAX706TEPA+?

The MR input on MAX706TEPA+ is active-low and TTL/CMOS-compatible. Pulling MR below 0.6V for ≥150ns (at VCC = 5V) forces RESET low for 200ms, regardless of VCC level. An internal 70µA pull-up current allows direct connection to a pushbutton switch tied to ground. When unused, MR should be left unconnected or tied to VCC-floating MR does not cause spurious resets due to the defined input threshold and hysteresis.