Analog Devices Inc./Maxim Integrated DS1706ESA+T&R

Overview

DS1706ESA+T&R from Maxim Integrated is a 5.0V ±10% microprocessor supervisory circuit that monitors VCC, provides pushbutton reset control, and implements a 1-second watchdog timer with WDS output. It delivers active-low reset (RST), non-maskable interrupt (NMI), and strobe input (ST) for embedded systems requiring reliable power-up sequencing and fault recovery in industrial environments.

For engineers reviewing the DS1706ESA+T&R datasheet, DS1706ESA+T&R pinout, DS1706ESA+T&R application, or DS1706ESA+T&R equivalent, key selection criteria include its 4.25V–4.50V VCC trip point, 130ms minimum reset pulse width, 1s watchdog timeout, -40°C to +85°C operation, and compatibility with 8-pin SOIC packaging.

Technical Context

The DS1706ESA+T&R integrates three independent monitoring functions: precision voltage detection using an internal 1.25V bandgap reference and comparator for VCC supervision; debounced pushbutton reset with guaranteed 130ms active-low RST assertion; and a monostable watchdog timer triggered by ST transitions, timing out after 1.0–2.2s to assert WDS low.

Its NMI output provides early power-fail warning with 200μs pulse width and 100μV hysteresis, while the IN pin enables external voltage sensing at user-defined points via resistor divider. All logic inputs (PBRST, ST) feature internal pull-ups (40kΩ/180kΩ typical), and outputs drive up to 10mA sink current at 0.4V.

Key Specifications

Pinout & Package

DS1706ESA+T&R is housed in an 8-pin SOIC (150-mil) package, RoHS-compliant and lead-free, with standard JEDEC MS-012AC outline and thermal pad omitted.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DS1706ESA+T&R, MAX706ESA+ offers drop-in replacement capability but omits the IN-sense function critical for predictive power failure response, while TPS3808G12DBVR trades integrated simplicity for configurability at the cost of added external parts and reduced fault coverage.

Availability

DS1706ESA+T&R is available at Aetrix Electronics and suitable for industrial automation, medical diagnostics, telecom infrastructure, and automotive infotainment systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for DS1706ESA+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, medical, communications, and computing applications.

The DS1706ESA+T&R belongs to the MicroMonitor™ family-engineered specifically for microprocessor supervision in harsh environments where deterministic reset behavior, early power-fail warning, and software watchdog enforcement are mandatory.

FAQ

What is the exact VCC trip point range for DS1706ESA+T&R?

The DS1706ESA+T&R has a factory-trimmed VCC trip point of 4.25V (minimum), 4.40V (typical), and 4.50V (maximum) at -40°C to +85°C. This ±10% tolerance around 5.0V ensures reliable reset activation before the microprocessor enters undefined operation, and is verified per Maxim's DS1705/DS1706 datasheet Rev 4/10, page 9.

Does DS1706ESA+T&R support both active-low and active-high reset outputs?

No, DS1706ESA+T&R provides only an active-low reset output (RST). The datasheet confirms this variant uses the "/RST" configuration (Ordering Info, page 11), distinguishing it from DS1706LESA+ which offers active-high RST. The DS1706ESA+T&R pinout shows RST as open-drain active-low, with no *RST terminal present.

How does the watchdog timer in DS1706ESA+T&R interact with the reset function?

The DS1706ESA+T&R watchdog timer starts timing only after RST becomes inactive (i.e., after power-up stabilization). A high-to-low transition on ST resets the 1.0–2.2s timeout; failure to do so triggers WDS low for ≥130ms. Crucially, WDS assertion does not directly drive RST-it signals fault condition externally, allowing system firmware to decide whether to initiate reset via PBRST or other means.

Can DS1706ESA+T&R monitor a 3.3V supply instead of 5.0V?

No, DS1706ESA+T&R is specifically configured for 5.0V ±10% monitoring (VCCTP = 4.25–4.50V). For 3.3V systems, Maxim offers variants like DS1706TESA+ (3.3V ±5%) or DS1706SESA+ (3.3V ±10%). Using DS1706ESA+T&R on 3.3V would result in permanent RST assertion since VCC remains below its 4.25V minimum trip point.

What is the purpose of the IN pin on DS1706ESA+T&R, and how is it used?

The IN pin on DS1706ESA+T&R is a high-impedance input referenced to an internal 1.25V bandgap, enabling external voltage monitoring upstream of VCC-such as at a DC-DC converter output or bulk capacitor. A resistor divider scales the target voltage to 1.25V at IN; when that voltage drops, NMI pulses low for ≥200μs, providing early warning before VCC itself fails.