Analog Devices Inc./Maxim Integrated DS1834DU

Overview

DS1834DU from Maxim Integrated (now Analog Devices) is a dual-voltage supervisor IC that monitors 5V and 3.3V power supplies with independent tolerance selection, pushbutton reset input, and CMOS push-pull reset outputs. It asserts active-low resets for each rail during out-of-tolerance conditions or manual override, maintains reset for 350 ms after recovery, and draws internal power from the higher of the two supply inputs. Used in embedded systems with dual-rail power domains requiring reliable power-on and brownout reset sequencing.

For engineers reviewing the DS1834DU datasheet, DS1834DU pinout, DS1834DU application, or DS1834DU equivalent, key selection criteria include dual-supply monitoring capability, selectable 5% / 10% / 20% trip-point tolerances per rail, 350 ms reset timeout, pushbutton debouncing, and operation across -40°C to +85°C industrial temperature range.

Technical Context

The DS1834DU integrates two independent voltage comparators with precision temperature-compensated references, enabling simultaneous monitoring of 5VIN and 3.3VIN rails. Each rail's trip point is configurable via dedicated TOL pins tied to GND or the respective supply, yielding 5%/10% (5V) or 10%/20% (3.3V) tolerance options.

It features an internally debounced PBRST input that forces both RST outputs active for ~350 ms after release, and uses a dynamic power-selection circuit that draws operating current exclusively from the higher of the two supply inputs. Reset outputs are CMOS push-pull (not open-drain), eliminating external pull-ups required by the DS1834A variant.

Key Specifications

Pinout & Package

DS1834DU is supplied in an 8-pin SOIC (150-mil) package with standard JEDEC MS-012AC footprint and 1.27 mm pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-voltage supervisor applications.

Compared with MAX6369CSA+ and TPS3808G33DBVR, the DS1834DU provides unique dual-rail independence, hardware-configurable tolerances, integrated pushbutton debouncing, and push-pull outputs-reducing design complexity and component count in systems requiring coordinated 5V/3.3V reset sequencing.

Availability

DS1834DU is available at Aetrix Electronics and suitable for industrial PLC controllers, medical diagnostic equipment, telecom line cards, and automotive infotainment head units requiring stable component supply and long-term lifecycle support.

Supply support for DS1834DU 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 (formerly Maxim Integrated) is a global leader in high-performance analog, mixed-signal, and power management semiconductors, serving industrial, automotive, communications, and healthcare markets.

The DS1834DU belongs to Maxim's EconoReset™ family of voltage supervisors, designed specifically for cost-effective, space-constrained dual-rail systems requiring reliable power-on and brownout reset without software intervention.

FAQ

What is the function of the 5V TOL and 3.3V TOL pins on the DS1834DU?

The 5V TOL and 3.3V TOL pins configure the trip-point tolerance for their respective supply rails. When tied to GND, 5V TOL selects ±5% tolerance (4.50–4.75 V), and 3.3V TOL selects ±10% (2.80–2.97 V). When tied to their supply voltage, they select ±10% (5V) or ±20% (3.3V). This hardware-based configuration eliminates firmware dependency and supports field-programmable reset thresholds in the DS1834DU.

Does the DS1834DU require external pull-up resistors on its RST outputs?

No, the DS1834DU does not require external pull-up resistors. Its 5V RST and 3.3V RST outputs are CMOS push-pull drivers capable of actively driving high or low. This differs from the DS1834A variant, which uses NMOS open-drain outputs and mandates external pull-ups. The DS1834DU's architecture reduces BOM count and simplifies layout for both reset lines.

How does the DS1834DU handle power sequencing when both 5VIN and 3.3VIN are present?

The DS1834DU dynamically selects the higher of the two supply inputs (5VIN or 3.3VIN) to power its internal circuitry. This ensures stable operation during asymmetric power-up or brownout sequences-for example, when 5V rises before 3.3V or vice versa. Both RST outputs remain functional as long as at least one supply exceeds 1.2 V, and the DS1834DU maintains valid reset states even during deep undervoltage conditions.

What is the reset timeout duration for the DS1834DU, and is it adjustable?

The DS1834DU asserts reset for 200–500 ms after a supply returns to tolerance or after PBRST release, with typical duration of 350 ms. This timeout is fixed by internal timing circuitry and is not user-adjustable via external components. The value ensures sufficient time for power stabilization and processor core initialization before releasing reset, meeting common microcontroller requirements without design iteration.

Can the DS1834DU operate with only one supply voltage applied?

Yes, the DS1834DU operates with only 5VIN or only 3.3VIN applied, provided the active supply is ≥1.2 V. If only 5VIN is present, the 3.3V RST output remains inactive (high), and vice versa. The PBRST function remains fully operational regardless of which supply is active. This flexibility supports legacy or hybrid systems where dual-rail operation is optional, and the DS1834DU retains full supervision capability on the powered rail.