Analog Devices Inc./Maxim Integrated DS1708EPA+

Overview

DS1708EPA+ from Maxim Integrated is a 5.0V ±10% microprocessor supervisory circuit that monitors VCC, senses external voltage via IN pin, and debounces pushbutton reset input (PBRST). It delivers active-low and active-high reset outputs (RST and RST), non-maskable interrupt (NMI), and guarantees ≥130ms reset pulse width. Used in industrial embedded systems requiring reliable power-up/power-down sequencing and early power-fail warning.

For engineers reviewing the DS1708EPA+ datasheet, DS1708EPA+ pinout, DS1708EPA+ application, or DS1708EPA+ equivalent, key selection criteria include VCC trip point accuracy (4.25–4.50V), dual reset polarity support, NMI timing (≥200ns pulse, 5µs detection delay), and compatibility with 3.3V/5.0V microprocessor supply rails under -40°C to +85°C operation.

Technical Context

The DS1708EPA+ integrates three independent monitoring functions: precision VCC threshold detection (4.25–4.50V), high-impedance IN-pin voltage sensing referenced to 1.25V internal bandgap, and debounced PBRST input with guaranteed 130ms reset assertion. All logic operates from a single 1.2–5.5V supply.

Its dual-reset architecture provides simultaneous active-low (RST) and active-high (RST) signals for direct interface with diverse microprocessor reset inputs, while NMI enables early power-fail warning with built-in 100µV hysteresis and noise immunity against <2µs transients at VCCTP.

Key Specifications

Pinout & Package

DS1708EPA+ is housed in an 8-pin plastic DIP (300-mil) package with standard through-hole footprint and 0.3-inch width. Pin assignments are fixed per mechanical drawing and validated across Maxim's DS1707/DS1708 family.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX708ESA+, DS1708EPA+ adds critical IN-pin monitoring for upstream supply health; versus TPS3823-50DBVR, it provides NMI-driven fail-safe response and dual-reset polarity-key for industrial systems requiring layered power integrity assurance.

Availability

DS1708EPA+ is available at Aetrix Electronics and suitable for industrial PLC controllers, medical diagnostic equipment, telecom remote terminal units, and energy metering gateways requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for DS1708EPA+ 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) is a semiconductor company specializing in analog, mixed-signal, and power management ICs for industrial, automotive, and communications markets.

The DS1708EPA+ belongs to Maxim's MicroMonitor™ family of supervisory circuits, designed specifically for robust microprocessor power integrity in mission-critical embedded systems operating across wide temperature and voltage ranges.

FAQ

What is the exact VCC trip point range for DS1708EPA+?

The DS1708EPA+ has a guaranteed VCC trip point range of 4.25V (minimum) to 4.50V (maximum) at -40°C to +85°C. This ±10% tolerance around 5.0V ensures reliable reset activation before microprocessor operational limits are exceeded. The DS1708EPA+ datasheet specifies this range under DC Electrical Characteristics, and it is validated across the full industrial temperature range. DS1708EPA+ does not support adjustable trip points - the threshold is fixed by internal precision reference design.

Does DS1708EPA+ support external voltage monitoring, and how is it implemented?

Yes, DS1708EPA+ supports external voltage monitoring via its IN pin, which compares an externally divided voltage against a precise 1.25V internal bandgap reference. A resistor divider (e.g., R1 = 26kΩ, R2 = 10kΩ) scales higher supply voltages (e.g., 11.88V max) down to the 1.25V trip threshold. The IN pin features ≤1µA leakage and built-in hysteresis to reject noise. DS1708EPA+ uses this function to provide early warning (via NMI) before VCC dropout occurs, enabling proactive system response.

What is the function of the two RST pins on DS1708EPA+?

DS1708EPA+ provides both RST (active-low, open-drain) and RST (active-high, push-pull) reset outputs to interface directly with microprocessors requiring either polarity. RST asserts low during power-up, power-down, or pushbutton events; RST asserts high under normal operation and goes low during reset. This eliminates external inverters or level translators. DS1708EPA+ guarantees ≥130ms minimum pulse width on both outputs, synchronized to VCC recovery or PBRST release.

Can DS1708EPA+ generate a reset pulse from a pushbutton without external components?

Yes, DS1708EPA+ includes internal debouncing and timing circuitry for the PBRST pin. When the pushbutton pulls PBRST low and is released, DS1708EPA+ automatically generates a clean, guaranteed ≥130ms reset pulse on both RST and RST outputs. No external RC network or Schmitt trigger is needed. DS1708EPA+ also supports connecting NMI to PBRST to auto-trigger reset upon external supply failure - a feature confirmed in Maxim's application diagrams.

Is DS1708EPA+ pin-compatible with other members of the DS1707/DS1708 family?

Yes, DS1708EPA+ shares identical pinout and package (8-pin DIP) with DS1707EPA+, DS1708REPA+, DS1708SEPA+, and DS1708TEPA+. All variants maintain the same PBRST/VCC/GND/IN/RST/RST/NC/NMI arrangement and electrical timing. However, trip points differ: DS1707EPA+ is 5V±5%, DS1708REPA+ is 3.3V±20%, etc. DS1708EPA+ is not pin-compatible with MAX707/MAX708 in SOIC or µSOP packages due to differing pin 5/6 assignments, though DIP versions are aligned.