Analog Devices Inc./Maxim Integrated DS1811-15/T&R

Overview

DS1811-15/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 failure or brownout events. It features a 4.13 V typical VCC trip point, 150 ms guaranteed reset pulse width, 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 controllers requiring reliable power-on reset and supply monitoring.

For engineers reviewing the DS1811-15/T&R datasheet, DS1811-15/T&R pinout, DS1811-15/T&R application, or DS1811-15/T&R equivalent, key selection criteria include trip voltage tolerance (±15%), reset timeout consistency, open-drain drive capability, thermal stability across industrial temperature range, and compatibility with 5 V logic systems requiring glitch-free reset assertion.

Technical Context

The DS1811-15/T&R integrates a temperature-compensated bandgap reference and comparator to detect VCC deviations below its factory-trimmed 4.13 V threshold. Upon detection, it asserts RST low immediately; after VCC recovery, it holds RST active for 150 ms (min 100 ms, max 300 ms) to ensure system stabilization.

Its open-drain output supports wired-OR configurations and interfaces directly with TTL/CMOS inputs. The internal 5.5 kΩ pull-up resistor eliminates external components in standard 5 V systems, while leakage current remains below 40 µA across full operating range.

Key Specifications

Pinout & Package

SOT-23-3 surface-mount package with 1.3 mm × 2.9 mm footprint and 0.95 mm height; RoHS-compliant, lead-free finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809SEUR+T and TPS3808G15DBVR, the DS1811-15/T&R delivers fixed 150 ms reset hold and integrated pull-up in minimal SOT-23-3 form - ideal for cost-sensitive, space-constrained 5 V microprocessor reset applications where ±15% trip tolerance is sufficient.

Availability

DS1811-15/T&R is available at Aetrix Electronics and suitable for industrial control systems, smart metering platforms, and network infrastructure equipment requiring stable component supply and long-term manufacturability.

Supply support for DS1811-15/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) designs high-performance analog, mixed-signal, and power management ICs for precision sensing, signal conditioning, and system supervision.

The DS1811-15/T&R belongs to the EconoReset family - engineered for cost-effective, single-supply voltage monitoring in resource-constrained embedded systems where reliability and simplicity outweigh programmability.

FAQ

What is the exact VCC trip point specification for DS1811-15/T&R?

The DS1811-15/T&R has a guaranteed VCC trip point range of 4.00 V to 4.24 V, with a typical value of 4.13 V. This ±15% tolerance is laser-trimmed at wafer test and applies across the full -40°C to +85°C operating temperature range. The DS1811-15/T&R uses this threshold to assert reset when the monitored 5 V supply falls below specification, ensuring deterministic behavior in industrial power environments.

Does DS1811-15/T&R require an external pull-up resistor on the RST pin?

No, the DS1811-15/T&R includes an internal 5.5 kΩ pull-up resistor on the open-drain RST output, eliminating the need for an external component in standard 5 V systems. This feature reduces BOM count and PCB area. An external pull-up may be added only if interfacing with higher-voltage logic (e.g., 12 V) or driving high-capacitance buses exceeding 10 pF.

How long does DS1811-15/T&R hold the reset signal active after VCC returns to tolerance?

The DS1811-15/T&R holds the RST signal active for 100–300 ms after VCC recovers to within tolerance, with a typical duration of 150 ms. This guaranteed timeout ensures microprocessors and supporting circuitry fully stabilize before release. The timing is internally generated and independent of external capacitors or resistors, providing consistent behavior across units and temperatures.

Can DS1811-15/T&R operate with supply voltages below 5 V?

Yes, the DS1811-15/T&R operates over a VCC range of 1.2 V to 5.5 V, though its 4.13 V trip point makes it most suitable for monitoring 5 V rails. At lower VCC (e.g., 3.3 V), the device remains functional but cannot assert reset - it will not trigger unless VCC exceeds the trip threshold. For 3.3 V systems, a variant like DS1811-33 would be appropriate.

What package type is supplied with DS1811-15/T&R?

The DS1811-15/T&R is supplied in the SOT-23-3 surface-mount package (1.3 mm × 2.9 mm × 0.95 mm), tape-and-reel format (T&R). This compact, RoHS-compliant package supports automated assembly and offers thermal performance suitable for industrial ambient conditions. Pinout matches standard SOT-23 pin 1 = RST, pin 2 = VCC, pin 3 = GND.