Analog Devices Inc./Maxim Integrated MXD1817UR23+

Overview

MXD1817UR23+ from Maxim Integrated is a low-power microprocessor reset supervisor IC with active-high push-pull RESET output, factory-set 2.31V reset threshold (±2.5% over temperature), 100ms minimum reset timeout, and operation down to VCC = +1V. It monitors +2.5V/+3.0V/+3.3V power supplies in portable and industrial embedded systems requiring reliable power-on reset and brownout protection.

For engineers reviewing the MXD1817UR23+ datasheet, MXD1817UR23+ pinout, MXD1817UR23+ application, or MXD1817UR23+ equivalent, key selection criteria include its active-high push-pull output drive capability, guaranteed reset validity at low VCC, precision threshold accuracy, transient immunity, and compatibility with space-constrained SOT23-3 layouts.

Technical Context

The MXD1817UR23+ integrates a precision voltage comparator with hysteresis, an internal 100ms reset timer, and a push-pull output stage. Its reset assertion logic triggers when VCC falls below 2.31V and holds RESET high for ≥100ms after VCC rises above threshold.

Designed for +2.5V–+3.3V systems, it guarantees correct RESET/RESET logic state down to VCC = +1V and rejects fast transients via built-in immunity circuitry. The device uses BiCMOS process technology and requires no external components for basic reset functionality.

Key Specifications

Pinout & Package

MXD1817UR23+ is housed in a 3-pin SOT23 package (U3-1 outline, land pattern 90-0179). Pin 1 is RESET (active-high push-pull output), Pin 2 is VCC (supply and threshold monitor input), and Pin 3 is GND.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MXD1817UR23+, MAX809TRD3+T demands board-level changes for signal polarity and pullup, while TPS3808G125DBVR trades simplicity and ultra-low ICC for adjustability-making MXD1817UR23+ optimal for cost-sensitive, space-constrained 3.3V systems needing guaranteed active-high timing.

Availability

MXD1817UR23+ is available at Aetrix Electronics and suitable for industrial controllers, portable instrumentation, set-top boxes, and battery-powered embedded systems requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for MXD1817UR23+ 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

Maxim Integrated (now part of Analog Devices) designs precision analog and mixed-signal ICs for industrial, computing, and communications markets.

The MXD1817UR23+ belongs to the MXD181x family of low-power μP reset supervisors, engineered specifically for reliable power-monitoring in space- and energy-constrained 2.5V/3.0V/3.3V embedded systems.

FAQ

What is the reset threshold voltage of the MXD1817UR23+ and how accurate is it over temperature?

The MXD1817UR23+ has a factory-set reset threshold of 2.31V with ±2.5% accuracy over the full operating temperature range of -40°C to +105°C. This specification is guaranteed by design and verified across temperature extremes, ensuring consistent brownout detection for 2.5V/3.0V/3.3V power rails without calibration. The MXD1817UR23+ maintains this accuracy using internal trimming and BiCMOS process stability.

Does the MXD1817UR23+ provide an active-high or active-low reset output, and what is its drive capability?

The MXD1817UR23+ features an active-high push-pull RESET output, meaning it drives the RESET pin high during reset assertion and low when released. It sources up to 350μA when asserted and sinks up to 10mA when deasserted at VOUT = 0.4V, eliminating the need for external pullup resistors. This configuration allows direct connection to microcontrollers requiring high-active reset signals, such as many ARM-based MCUs.

Can the MXD1817UR23+ operate reliably at very low supply voltages, and down to what level?

Yes, the MXD1817UR23+ is guaranteed to maintain correct RESET logic state down to VCC = +1.0V, as specified in its absolute maximum and operating characteristics. This ensures deterministic reset behavior during deep brownout or battery depletion scenarios. Unlike open-drain alternatives, its push-pull output remains well-defined across the entire 1.0V–5.5V supply range, making MXD1817UR23+ especially suitable for battery-powered applications where supply collapse must trigger controlled shutdown.

What is the reset timeout period of the MXD1817UR23+, and is it adjustable?

The MXD1817UR23+ provides a fixed reset timeout period of 100ms minimum, with typical values up to 150ms and a maximum of 250ms over temperature. This timeout is internally generated and non-adjustable, ensuring consistent reset hold time regardless of external component tolerances or layout parasitics. The fixed 100ms duration is optimized to meet μP initialization requirements for most 3.3V embedded systems, and MXD1817UR23+ delivers this timing without external capacitors or resistors.

Is the MXD1817UR23+ compatible with standard SOT23-3 footprints, and what is its package variant?

Yes, the MXD1817UR23+ uses the industry-standard 3-pin SOT23 package (outline U3-1, land pattern 90-0179), measuring 2.92mm × 1.3mm. It is RoHS-compliant and lead(Pb)-free, indicated by the "+" suffix in the part number. The SOT23-3 footprint ensures drop-in compatibility with existing layouts designed for similar supervisory ICs, and MXD1817UR23+ shares pinout and mechanical dimensions with other members of the MXD181x family in the same package.