Analog Devices Inc./Maxim Integrated DS1706SEUA+T&R

Overview

DS1706SEUA+T&R from Maxim Integrated is a 3.3V ±10% microprocessor supervisory circuit with active-low reset, watchdog timer, and non-maskable interrupt functions in an 8-pin µSOP package. It monitors VCC, detects software hangs via strobe input, and responds to pushbutton override - delivering 130 ms minimum reset pulse width and 1 s watchdog timeout for embedded control systems requiring reliable power-up/power-down sequencing.

For engineers reviewing the DS1706SEUA+T&R datasheet, DS1706SEUA+T&R pinout, DS1706SEUA+T&R application, or DS1706SEUA+T&R equivalent, key selection considerations include its 3.3V supply monitoring tolerance, industrial temperature range (–40°C to +85°C), µSOP-8 footprint compatibility with MAX705/MAX706, and integrated NMI generation at 1.25 V trip point on the IN pin.

Technical Context

The DS1706SEUA+T&R implements three independent monitoring functions: precision VCC detection (trip point 2.85–3.00 V, ±10% tolerance), debounced pushbutton reset with guaranteed 130 ms active-low RST pulse, and a 1-second watchdog timer triggered by ST input transitions. Its internal bandgap reference enables accurate voltage sensing at the IN pin, supporting external resistor dividers for upstream supply monitoring.

It generates two critical system signals: an active-low reset (RST) asserted during undervoltage or power-up (held ≥130 ms), and a non-maskable interrupt (NMI) pulsed for ≥200 µs when the monitored supply crosses the 1.25 V threshold. The WDS output asserts low upon watchdog timeout, enabling fail-safe recovery logic without processor intervention.

Key Specifications

Pinout & Package

DS1706SEUA+T&R is housed in an 8-pin µSOP (118-mil body width) package, RoHS-compliant and lead(Pb)-free per ordering suffix "+". Pin assignments are identical across DS1705/DS1706 family variants in this package type.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX706TESA+, DS1706SEUA+T&R trades ±5% accuracy for wider tolerance and lower cost in less-regulated 3.3V systems; versus TPS3808G18DBVR, it delivers integrated NMI and watchdog functionality without external components - reducing BOM count and board area.

Availability

DS1706SEUA+T&R is available at Aetrix Electronics and suitable for industrial automation, medical instrumentation, automotive electronics, and smart metering applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for DS1706SEUA+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) designs precision analog, mixed-signal, and power management ICs for industrial, communications, and computing markets.

The DS1706SEUA+T&R belongs to the MicroMonitor™ family - engineered specifically for microprocessor reliability in harsh environments, combining power monitoring, watchdog, and interrupt functions in a single compact package.

FAQ

What is the exact VCC trip point range for DS1706SEUA+T&R?

The DS1706SEUA+T&R has a guaranteed VCC trip point range of 2.85 V to 3.00 V, corresponding to ±10% tolerance around a nominal 3.3V supply. This specification is validated across the full industrial temperature range (–40°C to +85°C) and ensures reliable reset assertion before microprocessor malfunction occurs. The DS1706SEUA+T&R uses an internal temperature-compensated reference to maintain this accuracy without external calibration.

Does DS1706SEUA+T&R provide both active-high and active-low reset outputs?

No, DS1706SEUA+T&R provides only an active-low reset output (RST). It does not include the active-high *RST output found in DS1706L or DS1706P variants. The DS1706SEUA+T&R is specifically configured for /RST and /WDS operation, matching the DS1706EUA and DS1706TEUA pinouts. This simplifies design for systems requiring standard low-active reset signaling.

How does the watchdog timer in DS1706SEUA+T&R interact with the reset signal?

The DS1706SEUA+T&R watchdog timer starts timing only after RST becomes inactive (i.e., after power-up stabilization). If the ST input is not strobed low within 1.0–2.2 seconds, WDS asserts low for ≥130 ms - but this does not directly trigger RST. RST remains controlled solely by VCC level, PBRST, or power-up timing. Thus, WDS serves as a diagnostic flag, while RST handles hard system reset, enabling layered fault response in the DS1706SEUA+T&R architecture.

Can DS1706SEUA+T&R monitor a 5V supply?

No, DS1706SEUA+T&R is specified exclusively for 3.3V systems with ±10% tolerance (2.85–3.00 V trip). For 5V monitoring, Maxim offers DS1706EUA (±10%) or DS1705EUA (±5%). Attempting to use DS1706SEUA+T&R on a 5V rail would result in continuous RST assertion, as VCC exceeds its maximum operating voltage of 5.5V only marginally - but more critically, its trip point is not calibrated for 5V regulation. Always match the DS1706SEUA+T&R variant to the target supply voltage.

Is DS1706SEUA+T&R pin-compatible with MAX706 devices?

Yes, DS1706SEUA+T&R is pin-compatible with the MAX706 in 8-pin SOIC and µSOP packages, including identical pin functions and electrical behavior for RST, WDS, PBRST, ST, IN, NMI, VCC, and GND. This compatibility allows drop-in replacement in existing MAX706-based designs without PCB modification, provided the ±10% 3.3V trip point meets system requirements. The DS1706SEUA+T&R maintains the same timing parameters (e.g., 130 ms reset pulse) as the MAX706 family.