Analog Devices Inc./Maxim Integrated DS1834AU

Overview

DS1834AU from Maxim Integrated (now Analog Devices) is a dual-voltage power-on reset supervisor IC monitoring both 5V and 3.3V supplies with independent tolerance selection, pushbutton reset input, and CMOS push-pull reset outputs. It asserts active-low resets for 350 ms after supply recovery and draws internal current from the higher of the two supply inputs. Used in embedded systems requiring dual-rail power integrity assurance.

For engineers reviewing the DS1834AU datasheet, DS1834AU pinout, DS1834AU application, or DS1834AU equivalent, key selection criteria include dual-supply trip point configurability (5%–10% for 5V, 10%–20% for 3.3V), guaranteed 350 ms reset pulse width, push-pull output drive capability, -40°C to +85°C operation, and 8-pin SOIC package compatibility.

Technical Context

The DS1834AU integrates two independent voltage monitors with selectable trip thresholds via dedicated TOL pins-5V TOL tied to GND sets 5% tolerance (4.50–4.75 V), tied to 5VIN sets 10% (4.25–4.49 V); 3.3V TOL tied to GND sets 10% (2.80–2.97 V), tied to 3.3VIN sets 20% (2.47–2.64 V). Internal precision temperature-compensated reference ensures stable threshold tracking across temperature.

It features an internally debounced PBRST input with 2 ms minimum low-time detection and forces both RST outputs active for ~350 ms after release. Reset outputs are CMOS push-pull (not open-drain), eliminating external pull-ups required by the DS1834A variant, and maintain valid logic states down to 1.2 V supply-extendable to 0 V with optional external RST-to-GND resistor.

Key Specifications

Pinout & Package

DS1834AU is supplied in an 8-pin SOIC (150-mil) package with standard JEDEC MS-012AC footprint. Pin functions are electrically identical across DS1834 variants; AU suffix denotes SOIC packaging per Maxim's ordering nomenclature.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-supply reset supervision applications.

Compared with MAX6326UT46D3+ and TPS3808G33DBVR, the DS1834AU uniquely provides simultaneous 5V/3.3V monitoring with user-configurable trip tolerances and integrated pushbutton reset-enabling consolidated supervision with zero additional passives, critical for cost-sensitive dual-rail embedded designs.

Availability

DS1834AU is available at Aetrix Electronics and suitable for industrial PLC controllers, medical diagnostic equipment, telecom base station cards, and automotive infotainment head units requiring stable component supply with guaranteed long-term availability.

Supply support for DS1834AU 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

Analog Devices (via acquisition of Maxim Integrated) designs high-performance analog, mixed-signal, and power management ICs for precision sensing, power integrity, and reliable system supervision.

The DS1834AU belongs to Maxim's EconoReset™ family-engineered for cost-effective, dual-rail power monitoring in resource-constrained embedded systems where simplicity, configurability, and minimal external components are essential.

FAQ

What is the function of the 5V TOL and 3.3V TOL pins on the DS1834AU?

The 5V TOL and 3.3V TOL pins on the DS1834AU configure the voltage trip tolerance for each supply rail. Connecting 5V TOL to GND selects a 5% tolerance (4.50–4.75 V), while tying it to 5VIN selects 10% (4.25–4.49 V). Similarly, 3.3V TOL to GND gives 10% (2.80–2.97 V), and to 3.3VIN gives 20% (2.47–2.64 V). This allows precise matching to actual regulator specifications without redesigning the DS1834AU circuit.

Does the DS1834AU require external pull-up resistors on its reset outputs?

No, the DS1834AU does not require external pull-up resistors because it features CMOS push-pull outputs. Unlike the DS1834A (which has open-drain NMOS outputs), the DS1834AU actively drives both high and low states on 5V RST and 3.3V RST pins. This eliminates BOM items, reduces layout complexity, and improves noise margin in electrically noisy environments where the DS1834AU is deployed.

How long does the DS1834AU hold reset after power is restored to tolerance?

The DS1834AU holds both reset outputs active for a guaranteed 200–500 ms (typical 350 ms) after either 5VIN or 3.3VIN returns to its selected in-tolerance window. This timing applies identically during power-up, power-down recovery, and after PBRST release. The DS1834AU's internal timer ensures deterministic reset release regardless of supply slew rate, preventing premature processor boot before power stabilization.

Can the DS1834AU operate if only one supply rail is present?

Yes, the DS1834AU can operate with only one supply rail active. Its internal bias circuit automatically draws current from the higher of 5VIN or 3.3VIN, and outputs remain valid as long as at least one input is ≥1.2 V. If both supplies drop below 1.2 V, an external 100 kΩ resistor from RST to GND maintains valid low-state output down to 0 V-a feature confirmed in DS1834AU's functional specification and widely used in battery-fail scenarios.

What is the maximum supply voltage the DS1834AU can tolerate on its 5VIN and 3.3VIN pins?

The DS1834AU has an absolute maximum rating of +7.0 V on the 5VIN pin and +3.3VIN + 0.5 V on the 3.3V RST pin, but its recommended operating range is 1.2 V to 5.5 V for both 5VIN and 3.3VIN inputs. Exceeding 5.5 V risks permanent damage, and operation above this limit is outside the characterized performance envelope defined in the DS1834AU datasheet's Recommended DC Operating Conditions table.