Analog Devices Inc./Maxim Integrated DS1834DS+

Overview

DS1834DS+ from Analog Devices (acquired Maxim Integrated, formerly Dallas Semiconductor) is a dual-voltage power-on reset supervisor IC monitoring 5V and 3.3V supplies with pushbutton override. It features 5% or 10% 5V tolerance (selectable via 5V TOL pin), 10% or 20% 3.3V tolerance (via 3.3V TOL pin), 350 ms reset pulse width, CMOS push-pull outputs, and operates from −40°C to +85°C in 8-pin SOIC. Used in embedded systems requiring dual-rail power integrity.

For engineers reviewing the DS1834DS+ datasheet, DS1834DS+ pinout, DS1834DS+ application, or DS1834DS+ equivalent, key selection criteria include dual-supply trip point configurability, internal pushbutton debouncing, guaranteed 350 ms reset assertion after power recovery, and supply-source–adaptive current draw from the higher of 5VIN or 3.3VIN.

Technical Context

The DS1834DS+ integrates two independent voltage monitors with user-selectable tolerance thresholds (5V: 4.50–4.75 V at 5% tol or 4.25–4.49 V at 10% tol; 3.3V: 2.80–2.97 V at 10% tol or 2.47–2.64 V at 20% tol), each driving a dedicated active-low CMOS reset output. Its internal power-fail logic asserts resets during brownout or transient events on either rail.

It uses an internal temperature-compensated voltage reference and comparator circuitry for stable threshold detection across temperature. The PBRST input includes a 40 kΩ internal pull-up and hardware debouncing, enabling clean manual reset generation with ≥2 ms low pulse width and guaranteed 350 ms reset hold time post-release.

Key Specifications

Pinout & Package

DS1834DS+ is packaged in 8-pin SOIC (150-mil width), with pin 1 marked by a dot or notch. All pins are electrically identical to DS1834 and DS1834D variants; DS1834DS+ specifically denotes the SOIC package with standard CMOS push-pull outputs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6326US33D3+ and TPS3808G33DBVR, DS1834DS+ uniquely provides simultaneous 5V/3.3V monitoring with hardware-configurable thresholds and integrated pushbutton reset-enabling single-chip dual-rail supervision without layout changes or additional discretes.

Availability

DS1834DS+ is available at Aetrix Electronics and suitable for industrial automation, network infrastructure, medical diagnostics, and automotive infotainment systems requiring stable component supply and long-term obsolescence management.

Supply support for DS1834DS+ 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, Inc. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing technologies, serving industrial, automotive, communications, and healthcare markets.

The DS1834DS+ belongs to ADI's legacy power supervision portfolio (originally Dallas Semiconductor), designed specifically for robust dual-voltage system reset in space-constrained, thermally demanding embedded applications.

FAQ

What is the function of the 5V TOL and 3.3V TOL pins on the DS1834DS+?

The 5V TOL and 3.3V TOL pins on the DS1834DS+ configure the voltage trip thresholds for their respective rails. When tied to GND, 5V TOL selects a 5% tolerance (4.63 V typical trip), and 3.3V TOL selects 10% (2.88 V typical). When tied to their supply inputs, they select 10% (4.38 V) and 20% (2.55 V) tolerances respectively. This hardware-based configuration eliminates firmware dependency and ensures deterministic behavior at power-up.

Does the DS1834DS+ require external pull-up resistors on its reset outputs?

No, the DS1834DS+ does not require external pull-up resistors. Its 5V RST and 3.3V RST outputs are CMOS push-pull, capable of actively driving high or low states. This differs from open-drain alternatives like the DS1834A, which mandates external pull-ups. The DS1834DS+'s push-pull architecture reduces BOM count and improves noise immunity in dense PCB layouts.

How does the DS1834DS+ handle power supply sequencing during startup?

The DS1834DS+ asserts both reset outputs for approximately 350 ms after either 5VIN or 3.3VIN reaches its configured tolerance window. This ensures that all system components-including regulators, clocks, and processors-have fully stabilized before reset release. The device draws internal current from the higher of the two supplies, eliminating sequencing dependencies between the 5V and 3.3V rails.

Can the DS1834DS+ maintain valid reset output during deep brownout conditions?

Yes, the DS1834DS+ maintains valid reset output down to 1.2 V on either supply input. Its internal circuitry remains functional and continues asserting reset as long as at least one input exceeds 1.2 V. Below this level, a pull-down resistor (e.g., 100 kΩ) from RST to GND can preserve logic-low state even at 0 V input-enabling fail-safe behavior during catastrophic power collapse.

What is the minimum pulse width required on the PBRST pin to trigger a reset on the DS1834DS+?

The DS1834DS+ requires a low pulse of at least 2 ms on the PBRST pin to initiate a manual reset. The internal 40 kΩ pull-up ensures reliable default-high state, and hardware debouncing prevents false triggers from switch bounce. Once triggered, both 5V RST and 3.3V RST remain active for 350 ms after PBRST returns high, providing consistent override timing independent of firmware.