Analog Devices Inc./Maxim Integrated DS1811R-15/T&R

Overview

DS1811R-15/T&R from Maxim Integrated (now Analog Devices) is a precision voltage-monitoring supervisory IC that provides active-low reset signaling for microprocessors during power-up, power-down, and brownout events. It features a 4.13 V typical VCC trip point, 150 ms reset timeout, open-drain RST output with internal 5.5 kΩ pull-up, and operates from -40°C to +85°C in SOT-23 package. Used in embedded control systems requiring reliable power-fail detection and processor reset sequencing.

For engineers reviewing the DS1811R-15/T&R datasheet, DS1811R-15/T&R pinout, DS1811R-15/T&R application, or DS1811R-15/T&R equivalent, key selection criteria include trip voltage tolerance (±15%), reset pulse width consistency, open-drain drive capability, supply voltage range (1.2–5.5 V), and industrial temperature operation without external timing components.

Technical Context

The DS1811R-15/T&R implements a precision bandgap voltage reference and comparator-based monitoring circuit to detect when VCC falls below its factory-trimmed threshold of 4.00–4.24 V (15% tolerance). Its internal timing circuit ensures a guaranteed 100–300 ms reset assertion after VCC recovery, independent of external capacitors.

It delivers an open-drain RST output capable of sinking ≥10 mA at 0.4 V, with internal 3.5–7.5 kΩ pull-up resistor. The device draws only 30–40 µA quiescent current and supports supply voltages as low as 1.2 V, enabling compatibility with modern low-voltage microcontrollers.

Key Specifications

Pinout & Package

SOT-23-3 surface-mount package (2.92 mm × 1.3 mm × 1.0 mm), 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 MAX6326–41D and TPS3808G15, the DS1811R-15/T&R offers lowest BOM cost via integrated pull-up and relaxed tolerance-ideal for cost-sensitive industrial controls where ±15% trip variation is acceptable and open-drain flexibility suffices.

Availability

DS1811R-15/T&R is available at Aetrix Electronics and suitable for industrial automation, smart metering, and point-of-sale terminal designs requiring stable component supply, long-term manufacturability, and proven field reliability in temperature-varying environments.

Supply support for DS1811R-15/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) is a global leader in high-performance analog, mixed-signal, and digital signal processing technologies, serving industrial, automotive, communications, and healthcare markets.

The DS1811R-15/T&R belongs to Maxim's EconoReset™ family of supervisory ICs, designed specifically for cost-optimized, single-chip power-monitoring and reset generation in resource-constrained embedded systems.

FAQ

What is the exact VCC trip voltage range for DS1811R-15/T&R?

The DS1811R-15/T&R has a factory-set VCC trip point range of 4.00 V to 4.24 V, corresponding to a ±15% tolerance around the typical 4.13 V threshold. This range is specified under DC electrical characteristics at -40°C to +85°C and applies across the full 1.2–5.5 V supply range. The value is laser-trimmed during production and does not require external calibration.

Does DS1811R-15/T&R require an external pull-up resistor on the RST pin?

No, DS1811R-15/T&R includes an internal pull-up resistor ranging from 3.5 kΩ to 7.5 kΩ (typical 5.5 kΩ), eliminating the need for an external component in most applications. An external pull-up may be added only if the target MCU reset input requires stronger high-level drive or faster rise time than the internal resistor provides.

How long is the reset pulse duration after VCC returns to tolerance for DS1811R-15/T&R?

The DS1811R-15/T&R asserts the RST pin low for 100–300 ms after VCC rises above the trip threshold, with a typical duration of 150 ms. This fixed timeout is generated by an internal timer and does not depend on external capacitors or resistors, ensuring consistent reset hold time across operating conditions.

Can DS1811R-15/T&R operate with supply voltages below 3.3 V?

Yes, DS1811R-15/T&R supports supply voltages from 1.2 V to 5.5 V. Its internal voltage reference and comparator remain functional down to 1.2 V, making it suitable for low-voltage microcontrollers and battery-powered systems-even when VCC is derived from partially discharged cells or energy-harvesting sources.

Is DS1811R-15/T&R pin-compatible with other DS181x series devices?

Yes, DS1811R-15/T&R shares identical SOT-23-3 pinout (RST/VCC/GND) and functional behavior with DS1810, DS1812, DS1813, DS1815, DS1816, DS1817, and DS1818 variants. Only the trip voltage and tolerance differ between part numbers; all share the same timing, output structure, and package dimensions.