Analog Devices Inc./Maxim Integrated DS1815R-20

Overview

DS1815R-20 from Maxim Integrated (now Analog Devices) is a precision voltage-monitoring reset IC with push-pull active-low output, designed for microprocessor supervision in power-constrained systems. It asserts reset for 150ms after V_CC returns to tolerance, features ±20% V_CC trip point accuracy (2.47V–2.64V), operates from -40°C to +85°C, and uses a temperature-compensated reference for stable detection across voltage and temperature. It is commonly deployed in embedded controllers requiring reliable power-up sequencing.

For engineers reviewing the DS1815R-20 datasheet, DS1815R-20 pinout, DS1815R-20 application, or DS1815R-20 equivalent, key selection considerations include its 20% trip tolerance, push-pull output drive capability (10mA sink), 35µA typical supply current, SOT-23/TO-92 package options, and guaranteed reset assertion down to 0V V_CC.

Technical Context

The DS1815R-20 implements a comparator-based power monitor using an internal precision temperature-compensated voltage reference to detect V_CC deviations against a fixed threshold. Its reset timing is internally generated-no external capacitor required-and guarantees minimum 100ms and maximum 250ms active-reset duration after V_CC recovery.

It delivers a CMOS-compatible push-pull RST output capable of sinking 10mA while sourcing 350µA, enabling direct interface with microcontroller reset inputs without pull-up resistors. The device remains functional down to 0V V_CC, ensuring valid reset assertion during brownout and full power-down conditions.

Key Specifications

Pinout & Package

DS1815R-20 is available in both TO-92 and SOT-23 packages. Both variants share identical 3-pin configuration and pin functions.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6326–23D and TPS3808G12DBVR, the DS1815R-20 offers factory-trimmed 20% trip accuracy with zero external components, push-pull output eliminating pull-up resistors, and guaranteed 150ms reset hold-all in a proven industrial SOT-23 footprint ideal for cost-sensitive 3.3V microcontroller supervision.

Availability

DS1815R-20 is available at Aetrix Electronics and suitable for industrial PLC controllers, smart metering modules, point-of-sale terminals, and IoT edge sensor nodes requiring stable component supply and long-term manufacturability.

Supply support for DS1815R-20 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 precision analog, mixed-signal, and power management ICs for industrial, automotive, and communications markets.

The DS1815R-20 belongs to Maxim's EconoReset™ family-low-cost, single-supply voltage supervisors targeting cost-sensitive microprocessor reset applications where simplicity, reliability, and minimal external components are critical.

FAQ

What is the exact V_CC trip point range for DS1815R-20?

The DS1815R-20 has a guaranteed V_CC trip point range of 2.47V (minimum) to 2.64V (maximum) at -40°C to +85°C, corresponding to its ±20% tolerance specification. This range is factory-trimmed and does not require external calibration. The DS1815R-20 achieves this accuracy using an internal temperature-compensated voltage reference, ensuring stability across operating conditions.

Does DS1815R-20 require an external pull-up resistor on the RST pin?

No, the DS1815R-20 features a push-pull output stage that actively drives RST high when not asserted, eliminating the need for an external pull-up resistor. This reduces BOM count and PCB area. The DS1815R-20 can source up to 350µA and sink up to 10mA, making it compatible with standard CMOS reset inputs without additional components.

How long is the reset pulse duration of DS1815R-20 after V_CC recovers?

The DS1815R-20 guarantees a reset pulse duration between 100ms and 250ms after V_CC returns to within tolerance. The typical value is 150ms, and timing is fully internal-no external capacitor or resistor is required. This ensures consistent reset hold time across temperature and supply variations, critical for reliable microprocessor initialization in the DS1815R-20.

Can DS1815R-20 operate with V_CC below 1.0V?

Yes, the DS1815R-20 remains functional and asserts RST down to 0V V_CC, as confirmed in the "RST VALID TO 0 VOLTS VCC" application diagram. Its internal circuitry continues monitoring and asserting reset even during deep brownout or full power collapse, ensuring the DS1815R-20 releases reset only after V_CC rises above the 2.47–2.64V trip window and sustains for the internal timing period.

What package options are available for DS1815R-20?

The DS1815R-20 is offered in both TO-92 and SOT-23 packages. Both share identical pinout (RST-V_CC-GND) and electrical specifications. The SOT-23 variant supports automated surface-mount assembly and saves board space; the TO-92 version is suited for through-hole prototyping or legacy designs. No performance or timing differences exist between the two packages for the DS1815R-20.