Analog Devices Inc./Maxim Integrated DS1708SEUA+

Overview

DS1708SEUA+ from Maxim Integrated is a 3.3V ±10% microprocessor supervisory circuit that monitors VCC, provides pushbutton reset debouncing, and generates a non-maskable interrupt (NMI) for early power-fail warning. It delivers active-high and active-low reset outputs with 130ms minimum pulse width, operates across -40°C to +85°C, and uses an internal 1.25V reference for voltage sense input. It is used in embedded systems requiring reliable power-up/power-down sequencing and fault-aware reset control.

For engineers reviewing the DS1708SEUA+ datasheet, DS1708SEUA+ pinout, DS1708SEUA+ application, or DS1708SEUA+ equivalent, key selection considerations include its 3.3V supply monitoring tolerance, dual RST outputs, NMI timing behavior, PBRST debounce logic, and µSOP-8 package compatibility with space-constrained industrial controllers and IoT edge nodes.

Technical Context

The DS1708SEUA+ implements a precision bandgap-referenced comparator to monitor VCC against a fixed trip point of 2.85V–3.00V (DS1708S variant), while its IN pin accepts externally scaled voltages via resistor divider for upstream supply monitoring. Its NMI output asserts for ≥200ns upon IN falling below 1.20V–1.30V, with 100µV hysteresis and 5µs noise immunity.

Reset assertion is triggered when VCC drops below VCCTP, holding RST and RST active for ≥130ms during power-up and power-down. The PBRST input is internally pulled up (40kΩ typical) and debounced to guarantee ≥130ms reset pulses on button release - independent of mechanical bounce or contact time.

Key Specifications

Pinout & Package

DS1708SEUA+ is housed in an 8-pin µSOP (118-mil) package with exposed pad for thermal performance. Pin numbering follows standard SOIC/SOP orientation (pin 1 top-left, counterclockwise).

Key Features

Applications

Equivalent & Alternatives

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

Compared with DS1708SEUA+, MAX6326UT29D+ reduces feature count and package size but eliminates critical NMI functionality, while TPS3808G33DBVR improves trip accuracy at the expense of missing both RST and NMI - making DS1708SEUA+ uniquely suited for systems requiring coordinated fail-safe response with minimal external components.

Availability

DS1708SEUA+ is available at Aetrix Electronics and suitable for industrial PLC controllers, medical diagnostic devices, smart energy meters, and network edge gateways requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature performance.

Supply support for DS1708SEUA+ 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 U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, automotive, and communications markets.

The DS1707/DS1708 family was designed specifically for robust microprocessor supervision in harsh environments - delivering integrated voltage monitoring, pushbutton control, and early-warning interrupt capability in a single 8-pin package.

FAQ

What is the exact VCC trip point range for DS1708SEUA+?

The DS1708SEUA+ has a guaranteed VCC trip point range of 2.85V to 3.00V, corresponding to the DS1708S variant designation. This ±10% tolerance is calibrated for nominal 3.3V systems and is specified over the full -40°C to +85°C operating temperature range. The trip point is internally generated and does not require external calibration. DS1708SEUA+ maintains this specification under all recommended operating conditions, including varying load and slew rate.

Does DS1708SEUA+ provide both active-high and active-low reset outputs?

Yes, DS1708SEUA+ provides two independent reset outputs: RST (active-low, open-drain) and RST (active-high, push-pull). RST sinks ≥10mA at 0.4V, compatible with standard microcontroller /RESET inputs. RST sources ≥350µA at VCC–0.3V, directly driving CMOS logic inputs without external pull-ups. Both outputs are asserted simultaneously during power-up, power-down, or PBRST activation, with guaranteed ≥130ms minimum pulse width.

How does the NMI function work in DS1708SEUA+ and what is its timing behavior?

The NMI output in DS1708SEUA+ asserts low for ≥200ns when the voltage at the IN pin falls below 1.20V–1.30V (trip point), with 100µV hysteresis and 5µs noise immunity. It activates before RST/RST during power failure, providing early warning for system shutdown. NMI is disabled during initial power-up until VCC reaches VCCTP. DS1708SEUA+'s NMI timing is fully characterized in the datasheet's Figure 6 and AC Electrical Characteristics table (tIPD = 5–8µs).

Can DS1708SEUA+ monitor voltages higher than 3.3V, such as 5V or 12V rails?

Yes, DS1708SEUA+ can monitor higher-voltage rails using the IN pin with an external resistor divider. The internal reference is fixed at 1.25V, so resistor values are selected to scale the target rail (e.g., 5V or 12V) down to ≤1.25V at IN. The datasheet provides the formula VSENSE = (R2/(R1+R2)) × 1.25V and confirms proper operation requires IN voltage ≤ VCC. DS1708SEUA+'s high-impedance IN input (≤1µA leakage) minimizes divider current draw.

Is DS1708SEUA+ pin-compatible with other members of the DS1707/DS1708 family?

Yes, DS1708SEUA+ is pin-compatible with all DS1707/DS1708 variants in the same package type (µSOP-8), including DS1707EUA+, DS1708EUA+, DS1708TEUA+, and DS1708REUA+. Pin functions, layout, and mechanical dimensions are identical across the family. This allows drop-in replacement for different trip points (e.g., 5V vs. 3.3V, ±5% vs. ±10%) without PCB redesign - provided the application's voltage monitoring requirements align with the selected variant's VCCTP specification.