Analog Devices Inc./Maxim Integrated DS1817-5+T&R

Overview

DS1817-5+T&R from Maxim Integrated (now Analog Devices) is a precision voltage-monitoring supervisory IC that provides active-high reset signaling for microprocessors during power failure or brownout events. It features a 3.0V nominal trip point (2.98–3.15V), 150ms reset pulse width, push-pull output, and operates from -40°C to +85°C in SOT-23 package - used in embedded systems requiring reliable power-on reset and supply monitoring.

For engineers reviewing the DS1817-5+T&R datasheet, DS1817-5+T&R pinout, DS1817-5+T&R application, or DS1817-5+T&R equivalent, key selection criteria include its 5% VCC tolerance window, guaranteed 100–250ms reset assertion time, active-high CMOS output drive capability, and compatibility with 3.0V/3.3V logic systems.

Technical Context

The DS1817-5+T&R integrates a temperature-compensated bandgap reference and comparator to detect VCC deviations beyond ±5% of 3.0V. Its internal timing circuit ensures reset remains asserted for ≥100ms after VCC recovery, with typical hold time of 150ms and maximum of 250ms.

It delivers push-pull CMOS-level RST output capable of sourcing 350µA at 2.4V and sinking 10mA at 0.4V, with quiescent current under 35µA. The device requires no external components and supports direct connection to microcontroller reset inputs without pull-up resistors.

Key Specifications

Pinout & Package

SOT-23 surface-mount package (3-pin, 1.3mm × 2.9mm footprint), RoHS-compliant, tape-and-reel format (T&R).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage-monitoring reset applications.

Compared with MAX6326–UR31T and TPS3808G33DBVR, the DS1817-5+T&R offers tighter ±5% tolerance at 3.0V, guaranteed 150ms reset hold, and true push-pull drive - making it optimal for cost-sensitive, space-constrained 3.0V microcontroller reset applications where minimal BOM and fixed timing are critical.

Availability

DS1817-5+T&R is available at Aetrix Electronics and suitable for industrial control, smart metering, and IoT edge sensor applications requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for DS1817-5+T&R 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 reliability-critical systems.

The DS1817-5+T&R belongs to Maxim's EconoReset™ family - engineered for cost-effective, single-function power-supply monitoring and reset generation in resource-constrained embedded platforms.

FAQ

What is the exact VCC trip point range for DS1817-5+T&R?

The DS1817-5+T&R has a guaranteed VCC trip point range of 2.98V to 3.15V at -40°C to +85°C, corresponding to 3.0V ±5%. This specification is tested and binned per unit, ensuring tight tolerance compliance without external calibration. The DS1817-5+T&R uses an internal temperature-compensated reference to maintain this accuracy across its full operating temperature range.

Does DS1817-5+T&R require an external pull-up resistor on the RST pin?

No, the DS1817-5+T&R features a push-pull active-high output stage that actively drives the RST pin high during reset assertion and low during normal operation. This eliminates the need for an external pull-up resistor, reducing component count and simplifying layout. The DS1817-5+T&R can directly interface with standard CMOS/TTL reset inputs without additional passive components.

What is the reset timeout duration of DS1817-5+T&R after VCC recovery?

The DS1817-5+T&R holds the RST output active for 100–250ms after VCC returns to within tolerance, with a typical value of 150ms. This guaranteed minimum hold time ensures adequate stabilization of both the power supply and connected microprocessor before release from reset. The DS1817-5+T&R implements this timing internally with no external capacitor or configuration required.

Can DS1817-5+T&R operate with supply voltages below 3.0V?

Yes, the DS1817-5+T&R functions across a VCC range of 1.2V to 5.5V, but its 3.0V ±5% trip point remains valid only when VCC is stable within that operational window. Below ~2.0V, internal circuitry may not sustain accurate monitoring; however, the DS1817-5+T&R continues asserting reset as long as VCC stays out-of-tolerance. Its low 35µA quiescent current supports extended operation during brownout conditions.

Is DS1817-5+T&R compatible with 3.3V microcontrollers?

Yes, the DS1817-5+T&R is fully compatible with 3.3V microcontrollers: its RST output swings rail-to-rail (0V to VCC) and meets CMOS logic thresholds across the 1.2V–5.5V supply range. With a 3.3V VCC, the DS1817-5+T&R's 2.98–3.15V trip point provides robust brownout detection while maintaining noise margin. Its push-pull output ensures clean signal edges without rise-time degradation.