Analog Devices Inc./Maxim Integrated DS1708RESA+T&R

Overview

DS1708RESA+T&R from Maxim Integrated is a 3.3V ±20% supply voltage supervisor IC with dual active-high/active-low reset outputs, non-maskable interrupt (NMI), and pushbutton reset debouncing. It monitors VCC, an external sense point (IN), and PBRST to ensure microprocessor reliability during power transients and failures in industrial embedded systems. Key confirmed parameters: 2.55V–2.70V VCC trip point (DS1708R variant), 130ms minimum reset pulse width, -40°C to +85°C operating range, 8-pin SOIC package, and 50µA typical operating current at VCC < 3.6V.

For engineers reviewing the DS1708RESA+T&R datasheet, DS1708RESA+T&R pinout, DS1708RESA+T&R application, or DS1708RESA+T&R equivalent, this page delivers verified functional identity, precise reset thresholds, NMI timing behavior, pushbutton debounce characteristics, and direct compatibility context with MAX707/MAX708 - all critical for power sequencing validation and fail-safe system design.

Technical Context

The DS1708RESA+T&R implements a precision bandgap-referenced comparator architecture to monitor VCC against a fixed 2.63V nominal trip point (VCCTP = 2.55V/2.63V/2.70V) and the IN pin against a 1.25V internal reference. Its dual RST outputs provide simultaneous active-high and active-low reset signals with guaranteed 130ms minimum assertion time on power-up and power-down.

It integrates three independent monitoring paths: VCC supply tracking, high-impedance external voltage sensing via IN, and debounced pushbutton input (PBRST). The NMI output generates a 200µs minimum pulse with 100µV hysteresis when the IN voltage falls below 1.25V, enabling early power-fail warning before reset activation.

Key Specifications

Pinout & Package

DS1708RESA+T&R is housed in an 8-pin SOIC (150-mil) package with gull-wing leads, RoHS-compliant, and rated for industrial temperature operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor applications.

Compared with DS1708RESA+T&R, MAX708ESA+ offers simpler 5V-only supervision without sense flexibility, while TPS3808G18DBVR trades NMI functionality and SOIC robustness for tighter tolerance and smaller size - making DS1708RESA+T&R optimal for 3.3V systems requiring both precision reset timing and deterministic early-warning signaling.

Availability

DS1708RESA+T&R is available at Aetrix Electronics and suitable for industrial PLC controllers, medical diagnostic equipment, telecom radio units, and automotive infotainment head units requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for DS1708RESA+T&R 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 high-performance analog, mixed-signal, and power management solutions for industrial, communications, and computing markets.

The DS1707/DS1708 family was designed specifically for fail-safe microprocessor supervision in harsh environments, integrating VCC monitoring, external voltage sensing, and pushbutton control into a single compact IC to replace discrete reset circuits.

FAQ

What is the exact VCC trip point range for DS1708RESA+T&R?

The DS1708RESA+T&R is the DS1708R variant, specified with a VCC trip point of 2.55V (minimum), 2.63V (typical), and 2.70V (maximum) at -40°C to +85°C. This 20% tolerance window is calibrated for 3.3V nominal systems and is measured under recommended DC operating conditions with VCC between 1.2V and 5.5V. The DS1708RESA+T&R datasheet confirms these values in the "DC Electrical Characteristics" table under VCCTP for DS1708R.

Does DS1708RESA+T&R support external voltage monitoring, and how is it implemented?

Yes, DS1708RESA+T&R supports external voltage monitoring via its IN pin, which compares the applied voltage against an internal 1.25V bandgap reference (1.20V–1.30V range). A resistor divider network connects the target supply to IN, enabling programmable trip points - for example, monitoring a 12V rail by setting R1/R2 to produce 1.25V at the IN pin when the rail reaches 10.8V. The DS1708RESA+T&R datasheet provides the exact calculation formula and example in Figure 5.

How does the NMI output of DS1708RESA+T&R differ from the RST outputs in timing and function?

The NMI output of DS1708RESA+T&R generates a short, precise 200µs minimum low pulse when the IN voltage crosses the 1.25V threshold, serving as an early warning before full reset. In contrast, RST and RST remain asserted for ≥130ms once VCC drops below its trip point. This staged response allows DS1708RESA+T&R to initiate graceful shutdown (e.g., saving state) via NMI, then enforce hard reset via RST after power collapse - a key differentiator from basic reset supervisors.

Is DS1708RESA+T&R pin-compatible with the MAX707/MAX708 series, and what does that mean for PCB design?

Yes, DS1708RESA+T&R is pin-compatible with MAX707/MAX708 in 8-pin SOIC packages, sharing identical pin assignments for PBRST, VCC, GND, IN, RST, RST, NC, and NMI. This means DS1708RESA+T&R can be substituted onto existing MAX707/MAX708 layouts without PCB modification - provided the system operates at 3.3V ±20% and requires the same dual-reset and NMI functionality. The DS1708RESA+T&R datasheet explicitly states this compatibility in the Features section.

What is the guaranteed reset pulse width for DS1708RESA+T&R, and under what conditions is it enforced?

The DS1708RESA+T&R guarantees a minimum reset pulse width of 130ms for both RST and RST outputs, enforced during both power-up (VCC rising) and power-down (VCC falling) events. This timing is specified across the full -40°C to +85°C temperature range and for VCC between 1.2V and 5.5V. The DS1708RESA+T&R datasheet confirms this in the "AC Electrical Characteristics" table under parameter tRST and tRPU, with typical values of 205ms and maximum of 285ms.