Analog Devices Inc./Maxim Integrated DS1834

Overview

DS1834 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 supports systems with dual-rail power domains such as industrial controllers and embedded communication modules.

For engineers reviewing the DS1834 datasheet, DS1834 pinout, DS1834 application, or DS1834 equivalent, key selection criteria include dual-supply trip point configurability (5%–10% for 5V, 10%–20% for 3.3V), PBRST debounced manual reset timing, 350 ms reset timeout, and compatibility with 1.2 V minimum supply operation.

Technical Context

The DS1834 integrates two independent voltage monitors with user-selectable trip thresholds via dedicated TOL pins, enabling precise adaptation to system-specific 5V (4.50–4.75 V at 5% tol) and 3.3V (2.80–2.97 V at 10% tol) supply tolerances. Its internal power-fail detection logic generates reset signals only when either supply falls outside its configured window.

Reset assertion is synchronized across both rails during pushbutton events, with internal 40 kΩ pull-up and 2 ms debounce on PBRST. The device draws operating current from the higher of the two VIN inputs and maintains valid RST outputs down to 1.2 V using push-pull drivers - unlike the open-drain DS1834A variant requiring external pull-ups.

Key Specifications

Pinout & Package

DS1834 is available in 8-pin DIP (300-mil), 8-pin SOIC (150-mil), and 8-pin µ-SOP (118-mil) packages. All variants share identical pin mapping and function assignment.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6326 and TPS3808G33, the DS1834 delivers true dual-supply independence with zero external components, making it optimal for cost-sensitive, space-constrained designs where coordinated 5V/3.3V reset timing and pushbutton override are mandatory.

Availability

DS1834 is available at Aetrix Electronics and suitable for industrial PLC controllers, network router boards, medical diagnostic interfaces, and automotive infotainment head units requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for DS1834 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 system reliability.

The DS1834 belongs to Maxim's EconoReset family, engineered specifically for cost-effective, dual-rail power supervision in resource-constrained embedded systems without sacrificing accuracy or timing control.

FAQ

What is the reset polarity and output structure of the DS1834?

The DS1834 features active-low, push-pull reset outputs for both 5V RST and 3.3V RST. Unlike open-drain variants (e.g., DS1834A), it does not require external pull-up resistors. This design reduces component count and ensures defined logic levels across the full 1.2–5.5 V operating range, directly driving standard CMOS reset inputs without signal degradation.

How do the 5V TOL and 3.3V TOL pins configure trip thresholds?

The 5V TOL pin selects between 5% (when tied to GND, trip = 4.50–4.75 V) and 10% (when tied to 5VIN, trip = 4.25–4.49 V) tolerance for the 5V supply. Similarly, 3.3V TOL selects 10% (GND → 2.80–2.97 V) or 20% (3.3VIN → 2.47–2.64 V) for the 3.3V rail. These configurations are electrically validated and documented in the DS1834 datasheet Absolute Maximum and DC Characteristics tables.

Does the DS1834 support operation below 3.3V or 5V nominal supply levels?

Yes - the DS1834 operates from 1.2 V to 5.5 V on either input, with guaranteed functionality down to 1.2 V. Its internal reference and comparator remain accurate across this range, allowing valid reset assertion during brownout conditions where both 5VIN and 3.3VIN fall below nominal. This behavior is confirmed in the "Output Valid Conditions" section and Absolute Maximum Ratings table of the DS1834 datasheet.

What is the timing relationship between PBRST activation and reset assertion?

When PBRST is pulled low for ≥2 ms, both 5V RST and 3.3V RST go active immediately and remain asserted for 350 ms after PBRST returns high. This timing is internally generated and independent of supply slew rate. The 2 ms minimum pulse width and 350 ms timeout are production-tested parameters specified in the DS1834 AC Electrical Characteristics table under tPB and tRST.

Can the DS1834 be used in systems where 5V and 3.3V supplies power up at different rates?

Yes - the DS1834 monitors each supply independently. If 5VIN reaches tolerance first, its RST releases after 350 ms; 3.3V RST remains active until 3.3VIN stabilizes and satisfies its own trip condition. This staggered release prevents premature release of system reset when rails power up non-monolithically, a behavior verified in the DS1834 Power-Up Timing Diagram (Figure 9) and Operation section.