Analog Devices Inc./Maxim Integrated DS1706RESA

Overview

DS1706RESA from Maxim Integrated is a 3.3V ±20% supply voltage supervisor IC with active-low reset (/RST), watchdog status output (/WDS), and non-maskable interrupt (NMI) for microprocessor systems. It monitors VCC, detects power transients, debounces pushbutton reset, and provides 130ms minimum reset pulse width and 1s watchdog timeout. Used in embedded controllers requiring reliable power-up sequencing and fail-safe restart.

For engineers reviewing the DS1706RESA datasheet, DS1706RESA pinout, DS1706RESA application, or DS1706RESA equivalent, key selection criteria include its 3.3V ±20% trip point (VCCTP = 2.85–3.00V), industrial temperature range (–40°C to +85°C), SOIC-8 package, and compatibility with pushbutton override and external voltage sensing via IN pin.

Technical Context

The DS1706RESA implements three independent monitoring functions: precision VCC detection using an internal bandgap reference (VTP = 1.25V), pushbutton reset debouncing with guaranteed 130ms active-low RST pulse, and a 1-second watchdog timer triggered by ST input strobes. Its NMI output provides early warning of power decay before reset assertion.

All logic outputs are CMOS-compatible with rail-to-rail swing; /RST and /WDS drive low with 10mA sink capability, while inputs (PBRST, ST, IN) feature internal pull-ups (40kΩ/180kΩ typical). The device operates across 1.2V–5.5V supply range but is configured specifically for 3.3V ±20% monitoring per ordering code RESA.

Key Specifications

Pinout & Package

DS1706RESA 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 MAX706TESA and TPS3808G18DBVR, DS1706RESA uniquely integrates VCC supervision, NMI, pushbutton reset, and watchdog in one SOIC-8 device with 3.3V ±20% tolerance-ideal for cost-sensitive, function-rich industrial controllers where board space and BOM count matter.

Availability

DS1706RESA is available at Aetrix Electronics and suitable for industrial automation, medical diagnostics, smart metering, and automotive telematics requiring stable component supply and long-term lifecycle support.

Supply support for DS1706RESA 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 DS1706RESA belongs to the MicroMonitor™ family-engineered to provide integrated power supervision, reset control, and watchdog safety for microprocessor-based systems operating in harsh environments.

FAQ

What is the exact VCC trip point range for DS1706RESA?

The DS1706RESA has a guaranteed VCC trip point (VCCTP) of 2.85V (min) to 3.00V (max), corresponding to ±20% tolerance around 3.3V nominal. This range is specified over the full industrial temperature range (–40°C to +85°C) and ensures reliable reset assertion during brownout conditions. The DS1706RESA datasheet confirms this value under "DC Electrical Characteristics" for the DS1706S variant, which matches the RESA ordering code.

Does DS1706RESA support external voltage monitoring beyond VCC?

Yes, DS1706RESA supports external voltage monitoring via its IN pin, which features a precise 1.25V internal reference comparator. By connecting a resistor divider from the target supply to IN, users can monitor voltages up to ~11.88V (at VCC = 3.3V). The DS1706RESA datasheet provides the calculation formula and example in Figure 5, confirming this capability is fully functional and characterized for the DS1706RESA variant.

What is the watchdog timeout behavior of DS1706RESA?

The DS1706RESA watchdog timer times out after 1.0–2.2 seconds if the ST input is not strobed low before expiration. Upon timeout, /WDS goes active-low for ≥130ms. The timer starts when /RST becomes inactive (i.e., after power-up stabilization), and each ST falling edge resets the counter. This behavior is explicitly defined in the DS1706RESA datasheet's AC Electrical Characteristics table (tTD parameter) and Operation section.

Is DS1706RESA pin-compatible with MAX705/MAX706?

Yes, DS1706RESA is pin-compatible with the MAX705 and MAX706 in 8-pin SOIC packages, as confirmed in the "Features" section of the DS1706RESA datasheet: "Pin-compatible with the MAXIM MAX705/MAX706 in 8-pin DIP, 8-pin SOIC, and -SOP." All eight pins (PBRST, VCC, GND, IN, NMI, ST, /RST, /WDS) map identically in function and position between DS1706RESA and MAX706ESA.

What is the maximum allowable voltage on the IN pin of DS1706RESA?

The IN pin of DS1706RESA must not exceed VCC, as stated in the datasheet: "Proper operation … requires that the voltage at the IN pin be limited to VCC." While the absolute maximum rating allows up to VCC + 0.5V on I/O pins, the functional specification mandates IN ≤ VCC to prevent damage or incorrect sensing. This constraint is critical when designing external dividers and is explicitly called out in the "Operation" section for DS1706RESA.