Analog Devices Inc./Maxim Integrated DS1830A

Overview

DS1830A from Maxim Integrated is a 3.3V precision reset sequencer IC that monitors VCC for out-of-tolerance conditions and generates three time-sequenced, open-drain active-low reset outputs (RST1, RST2, RST3). It features selectable VCC trip points (2.47–3.15V), pushbutton reset input (PBRST), time-delay select (TD), tolerance-select input (TOL), and operates from -40°C to +85°C in 8-pin DIP packaging. Used in multi-rail power-up sequencing for FPGA-based industrial controllers.

For engineers reviewing the DS1830A datasheet, DS1830A pinout, DS1830A application, or DS1830A equivalent, key selection considerations include its 3.3V-specific trip thresholds, programmable reset timing (10–500ms), triple-output sequencing order, TOL/TD configuration flexibility, and compatibility with systems requiring deterministic power-on initialization under varying supply slew rates.

Technical Context

The DS1830A implements a precision temperature-compensated voltage reference and comparator to detect VCC deviations against three user-selectable trip thresholds (2.47–3.15V), sampled only while VCC remains below the lowest trip point. Its internal oscillator drives a clock chain that generates fixed-ratio delays: RST2 = 5×RST1, RST3 = 10×RST1, with minimum RST1 durations of 10ms (TD=GND), 20ms (TD=open), or 50ms (TD=VCC).

Reset assertion is triggered by either VCC dropout or a ≥1ms low pulse on PBRST - debounced internally with a 40kΩ pull-up. All outputs remain active until VCC stabilizes within tolerance, then release in strict sequence: RST1 first, followed by RST2, then RST3 - enabling controlled power-up of cascaded voltage domains in embedded systems.

Key Specifications

Pinout & Package

DS1830A is housed in an 8-pin DIP (300-mil) package with through-hole mounting and standard 0.3" row spacing. Pin 1 is marked with a notch or dot; pin numbering follows counter-clockwise convention from top-left corner.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar reset sequencing applications.

Compared with MAX6369 and TPS3808G33, the DS1830A uniquely delivers three precisely ratioed reset outputs with user-selectable trip thresholds and base delays - making it irreplaceable in systems requiring guaranteed, component-free, multi-rail power sequencing without microcontroller intervention.

Availability

DS1830A is available at Aetrix Electronics and suitable for FPGA power-up sequencing, industrial PLC controller boot, medical diagnostic imaging modules, and automotive infotainment head units requiring stable component supply and long-term industrial temperature support.

Supply support for DS1830A 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) designs precision analog, mixed-signal, and power management ICs for industrial, medical, and communications applications.

The DS1830A belongs to Maxim's reset supervisor and sequencer product line, engineered specifically for deterministic, multi-rail power-up control in 3.3V systems where reliability and timing predictability are critical.

FAQ

What is the VCC trip voltage range for DS1830A?

The DS1830A supports three selectable VCC trip points based on the TOL pin state: 2.47–2.64V (TOL open), 2.80–2.97V (TOL grounded), or 2.98–3.15V (TOL tied to VCC). These ranges are specified over -40°C to +85°C and reflect ±5% to ±20% tolerance around 3.3V, enabling precise matching to actual 3.3V rail behavior in the target system. The DS1830A datasheet confirms these values in the DC Electrical Characteristics table.

How does the DS1830A generate its three reset outputs with fixed timing ratios?

The DS1830A uses an internal oscillator and clock chain to produce RST1, RST2, and RST3 with hardwired timing relationships: RST2 activates 5× longer than RST1, and RST3 activates 10× longer than RST1. The base RST1 delay (10ms/20ms/50ms) is selected via the TD pin, and all outputs release sequentially after VCC stabilizes - ensuring deterministic, repeatable power-up order without external components. This architecture is detailed in the DS1830A timing diagrams and block diagram.

Can DS1830A be used in a 5V system?

No - the DS1830A is specifically characterized and specified for 3.3V operation, with trip thresholds centered around 2.98–3.15V (TOL=VCC). Its electrical specifications, including VCCTP min/max values and recommended operating conditions, are defined only for 3.3V-compatible applications. For 5V systems, the pin-compatible DS1830 (not DS1830A) must be used, as confirmed in the DS1830/A ordering table and DC characteristics section.

What is the function of the PBRST pin on DS1830A?

The PBRST pin on DS1830A is an active-low pushbutton reset input with internal 40kΩ pull-up and digital debounce. Pulling PBRST low for ≥1ms initiates a full reset sequence: all three outputs go active, then release in order (RST1 → RST2 → RST3) based on the TD-selected timing. This allows manual system reset without external circuitry. The DS1830A datasheet specifies PBRST timing and electrical behavior in the "Operation - Pushbutton Reset" section and AC Electrical Characteristics table.

Does DS1830A support cascading with another DS1830A for extended sequencing?

Yes - the DS1830A supports cascade configurations using RST3 output to drive PBRST of a second DS1830A (or DS1830), as shown in Figure 4 of the datasheet. To ensure correct ripple-through behavior, the master device's VCCTP must be set higher than the slave's (e.g., master TOL=VCC, slave TOL=GND), guaranteeing the master detects undervoltage first and triggers the slave's reset. This technique extends sequencing beyond three stages while maintaining deterministic timing.