Analog Devices Inc./Maxim Integrated DS1816R-5-U

Overview

DS1816R-5-U from Maxim Integrated (now Analog Devices) is a precision 3.3V microprocessor supervisory circuit with open-drain active-low reset output, 3.06V trip point (±5%), 150ms reset timeout, and internal 5kΩ pull-up resistor. It monitors VCC in embedded systems to ensure reliable power-on reset and brownout recovery.

For engineers reviewing the DS1816R-5-U datasheet, DS1816R-5-U pinout, DS1816R-5-U application, or DS1816R-5-U equivalent, key selection criteria include reset threshold accuracy, guaranteed reset pulse width, operating temperature range (-40°C to +85°C), SOT-23 package compatibility, and open-drain drive capability for shared bus reset signaling.

Technical Context

The DS1816R-5-U integrates a temperature-compensated voltage reference and comparator to detect VCC deviations beyond ±5% of nominal 3.3V (trip point 2.98–3.15V). Its internal timing circuit ensures a minimum 100ms and typical 150ms active-low reset assertion after power return.

It features an open-drain RST output with internal 5kΩ pull-up (3.5–7.5kΩ range), supports supply voltages from 1.2V to 5.5V, draws only 28–35µA quiescent current, and operates across industrial temperature range without external components.

Key Specifications

Pinout & Package

SOT-23-3 surface-mount package (3.0mm × 1.7mm × 1.3mm), RoHS-compliant, lead-free, and optimized for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor supervisory applications.

Compared with MAX6326–33D and TPS3808G33DBVR, the DS1816R-5-U provides cost-optimized, fixed-timing supervision with integrated pull-up and minimal BOM impact-ideal for high-volume industrial controllers where ±5% trip accuracy and 150ms hold meet functional safety targets without added complexity.

Availability

DS1816R-5-U is available at Aetrix Electronics and suitable for industrial PLC controllers, medical sensor nodes, smart energy meters, and automotive body control modules requiring stable component supply and long-term lifecycle support.

Supply support for DS1816R-5-U 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 (acquired Maxim Integrated in 2021) designs high-performance analog, mixed-signal, and power management ICs for precision sensing, signal conditioning, and system supervision.

The DS1816R-5-U belongs to Maxim's EconoReset™ family-engineered for cost-sensitive, space-constrained embedded systems needing reliable, single-chip power monitoring and reset generation without external timing components.

FAQ

What is the exact VCC trip point range for DS1816R-5-U?

The DS1816R-5-U has a guaranteed VCC trip point range of 2.98V to 3.15V at -40°C to +85°C, corresponding to ±5% tolerance around 3.06V nominal. This specification is tested and binned per device, ensuring consistent brownout detection behavior across all units of DS1816R-5-U in production lots.

Does DS1816R-5-U require an external pull-up resistor on the RST pin?

No, DS1816R-5-U includes an internal 5kΩ pull-up resistor on the RST pin. An external pull-up is only needed if the load capacitance or sink current exceeds the internal resistor's capability-typically when driving multiple devices or long traces. Most single-MCU applications operate correctly using the internal pull-up alone.

Can DS1816R-5-U be used with 5V microcontrollers?

Yes, DS1816R-5-U supports VCC supply voltages up to 5.5V and its open-drain RST output is compatible with 5V logic levels when pulled to the target MCU's VDD. The trip point remains fixed at ~3.06V, making it suitable for monitoring 3.3V rails in mixed-voltage systems containing 5V peripherals or MCUs.

What is the minimum reset pulse width guaranteed by DS1816R-5-U?

The DS1816R-5-U guarantees a minimum reset pulse width of 100ms and a typical value of 150ms after VCC returns to tolerance. This meets or exceeds JEDEC and common microcontroller requirements for power-up stabilization, and is fully characterized across temperature and supply voltage variations per the official DS1816R-5-U datasheet.

Is DS1816R-5-U available in TO-92 package?

No, DS1816R-5-U is specified and shipped exclusively in the SOT-23-3 package. While the DS1816 family includes TO-92 variants (e.g., DS1816R-5), the "-U" suffix denotes the SOT-23-3 variant per Maxim's part numbering convention and packaging documentation.