Analog Devices Inc./Maxim Integrated DS1831C

Overview

DS1831C from Maxim Integrated is a multisupply voltage monitor IC that supervises up to four system rails: 2.5V supply, 3.3V supply, and two user-configurable sense inputs (IN1, IN2). It provides dual open-drain reset outputs (RST2.5V, RST3.3V), non-maskable interrupts (NMI1, NMI2), master pushbutton reset (MPBRST), and configurable tolerance (±5%, ±10%, ±15% for 2.5V; ±5%, ±10%, ±20% for 3.3V) and reset delay (10ms/100ms/1s). It operates from −40°C to +85°C in 16-pin DIP or SO packages and is used in embedded systems requiring robust power sequencing and fault detection.

For engineers reviewing the DS1831C datasheet, DS1831C pinout, DS1831C application, or DS1831C equivalent, this page delivers verified specifications, validated pin functions, confirmed reset timing behavior, tolerance configuration logic, and real-world use cases for multi-rail industrial and telecom power monitoring.

Technical Context

The DS1831C uses an internal 1.25V temperature-compensated bandgap reference to compare input voltages against programmable trip points. Its dual comparator architecture enables independent monitoring of IN2.5V and IN3.3V with selectable tolerances via TOL2.5V/TOL3.3V pins, and independent reset delays via TD2.5V/TD3.3V pins - each supporting GND/float/VCC configurations for 10ms/100ms/1s delays.

Internal power is sourced from the higher of IN2.5V or IN3.3V (≥1.0V required for operation); both must exceed 1.5V for accurate voltage monitoring. The device asserts active-low open-drain resets during undervoltage conditions and maintains them for the selected delay after recovery. Pushbutton inputs (PBRST2.5V, PBRST3.3V, MPBRST) are internally pulled up to their respective supply rails with 100kΩ resistors and debounced.

Key Specifications

Pinout & Package

DS1831C is available in 16-pin 300mil DIP and 16-pin 150mil SO packages. Both share identical pin numbering and function mapping.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multisupply monitoring applications.

Compared with MAX6369 and TPS3808G33, DS1831C uniquely integrates dual-rail supervision, user-configurable tolerance/delay, two NMI channels, and three pushbutton interfaces - making it irreplaceable in systems requiring coordinated multi-voltage fault response and diagnostic visibility.

Availability

DS1831C is available at Aetrix Electronics and suitable for telecom infrastructure, industrial automation, medical imaging, and automotive infotainment applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for DS1831C 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 semiconductor company specializing in precision analog, mixed-signal, and power management ICs for industrial, communications, and computing markets.

The DS1831C belongs to Maxim's MicroMonitor™ family - designed specifically for high-reliability multi-rail power supervision in systems where coordinated reset timing, fault logging, and manual override capability are critical.

FAQ

What voltage rails does the DS1831C monitor?

The DS1831C monitors two primary supply rails: the 2.5V supply (IN2.5V) and the 3.3V supply (IN3.3V). It also provides two additional user-configurable sense inputs (IN1 and IN2) that can monitor other system voltages - such as 5V or 12V - using external resistor dividers scaled to the internal 1.25V reference. This allows DS1831C to supervise up to four distinct voltage domains in a single package.

How does the DS1831C determine its internal power source?

The DS1831C draws internal operating current from the higher of the two supply inputs: IN2.5V or IN3.3V. At least one of these inputs must be ≥1.0V for basic device operation, and both must exceed 1.5V for accurate voltage monitoring functionality. The internal bias circuitry automatically selects the dominant rail - eliminating the need for external power switching or OR-ing diodes in dual-supply systems.

Can the DS1831C generate different reset delays for the 2.5V and 3.3V rails?

Yes, the DS1831C supports independent reset delay configuration for each monitored rail. The TD2.5V pin sets the active duration of RST2.5V (10ms/100ms/1000ms), while TD3.3V sets RST3.3V's delay using identical logic. This enables precise power sequencing - for example, holding the 3.3V reset active longer than the 2.5V reset to allow slower peripherals to stabilize before processor release.

What is the function of the NMI1 and NMI2 pins on the DS1831C?

NMI1 and NMI2 are open-drain non-maskable interrupt outputs tied to the IN1 and IN2 sense inputs. When the voltage at IN1 or IN2 drops below the 1.25V internal reference (with 100µV hysteresis), the corresponding NMI pin pulses low for ≥20µs. These signals provide early fault indication before full reset assertion - enabling firmware to log events, trigger diagnostics, or initiate controlled shutdown without processor masking.

Does the DS1831C require external pull-up resistors on its outputs?

Yes, all DS1831C outputs - including RST2.5V, RST3.3V, NMI1, NMI2, and MPBRST - are open-drain and require external pull-up resistors to establish valid high-level logic states. A typical value is 10kΩ connected to the appropriate supply rail (e.g., 3.3V for RST3.3V). Pull-ups are mandatory for proper reset signaling and interrupt generation; omission will result in undefined or floating output behavior.