Analog Devices Inc./Maxim Integrated MAX6386XS23D3+T

Overview

MAX6386XS23D3+T from Maxim Integrated is a low-power microprocessor supervisory circuit with open-drain active-low reset output, factory-set 2.31V reset threshold (±2.5% over −40°C to +125°C), 140ms minimum VCC reset timeout, and debounced manual reset input (MR) featuring internal 63kΩ pullup. It operates from 1.0V to 5.5V supply and consumes only 3μA at 1.8V, enabling reliable power monitoring in battery-powered embedded systems.

For engineers reviewing the MAX6386XS23D3+T datasheet, MAX6386XS23D3+T pinout, MAX6386XS23D3+T application, or MAX6386XS23D3+T equivalent, key selection criteria include its 2.31V reset threshold accuracy, 140ms reset timeout, MR input timing behavior, open-drain output compatibility with mixed-voltage systems, and SC70-4 package footprint constraints.

Technical Context

The MAX6386XS23D3+T implements a precision voltage comparator with ±2.5% threshold accuracy across −40°C to +125°C, coupled to a monostable timer that guarantees minimum 140ms reset assertion after VCC recovery. Its MR input accepts TTL/CMOS logic levels and features internal 63kΩ pullup, eliminating external components for basic manual reset functionality.

As an open-drain active-low reset device, it requires an external pullup resistor on the RESET line and supports level-shifting across voltage domains. The reset output remains valid down to VCC = 1.0V, ensuring deterministic behavior during brownout conditions without requiring auxiliary power rails.

Key Specifications

Pinout & Package

MAX6386XS23D3+T is housed in a RoHS-compliant 4-pin SC70 package (outline 21-0098, land pattern 90-0187), measuring 2.0mm × 2.1mm × 0.95mm. This compact footprint supports high-density PCB layouts in space-constrained portable electronics.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6326XR23D3+T and TPS3123E18DBVR, the MAX6386XS23D3+T uniquely combines factory-trimmed 2.31V threshold, 140ms timeout, debounced MR input, and open-drain output in a 4-pin SC70 package-enabling compact, low-power, and serviceable reset solutions where manual intervention and mixed-voltage compatibility are essential.

Availability

MAX6386XS23D3+T is available at Aetrix Electronics and suitable for industrial PLC I/O modules, automotive body control units, portable medical sensors, smart energy meters, and battery-powered instrumentation requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6386XS23D3+T 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 demanding industrial, automotive, and communications applications, emphasizing low power, high reliability, and small form factors.

The MAX6381–MAX6390 family delivers single/dual low-voltage microprocessor supervisory circuits optimized for space-constrained, battery-operated, and thermally harsh environments-prioritizing guaranteed reset behavior down to 1.0V and ±2.5% threshold accuracy over −40°C to +125°C.

FAQ

What is the exact reset threshold voltage of the MAX6386XS23D3+T and how stable is it over temperature?

The MAX6386XS23D3+T has a factory-set nominal reset threshold of 2.31V, with guaranteed tolerance of ±2.5% over the full operating temperature range of −40°C to +125°C. Its temperature coefficient is 60ppm/°C, meaning threshold drift is limited to approximately ±15mV across the entire range - sufficient for robust 2.5V rail supervision without external trimming.

Does the MAX6386XS23D3+T require an external pullup resistor on the RESET pin, and why?

Yes, the MAX6386XS23D3+T requires an external pullup resistor on the RESET pin because it features an open-drain active-low output. Without the pullup, the RESET line would float high during deassertion, risking undefined logic states. A typical value is 10kΩ to 100kΩ connected to the target microcontroller's I/O voltage rail (e.g., 3.3V), ensuring clean level translation and adequate sink current during reset assertion.

How does the manual reset (MR) input of the MAX6386XS23D3+T behave during and after activation?

When the MR input of the MAX6386XS23D3+T is pulled low, reset asserts immediately and remains asserted for the full 140ms timeout period after MR returns high. The input includes internal 63kΩ pullup and rejects glitches shorter than 100ns. MR can be driven directly by a momentary switch to GND or by CMOS/TTL logic, and no external debounce components are required for typical use cases.

Can the MAX6386XS23D3+T operate reliably at VCC = 1.2V, and what happens to the reset output below its specified minimum?

Yes, the MAX6386XS23D3+T is guaranteed to function correctly down to VCC = 1.0V, including valid reset assertion and deassertion. At VCC = 1.2V, the 2.31V reset threshold is still enforced relative to the internal reference, so reset will assert if VCC falls below 2.31V - though this condition cannot occur at 1.2V supply. Below 1.0V, reset behavior is not characterized; design practice mandates ensuring VCC never drops below 1.0V during operation.

Is the MAX6386XS23D3+T pin-compatible with older Maxim reset ICs like the MAX809 or MAX6326?

No, the MAX6386XS23D3+T is not pin-compatible with MAX809 (3-pin SOT23) or MAX6326 (3-pin SOT23), as it uses a 4-pin SC70 package with dedicated MR and GND pins. While functionally similar to MAX6326XR23D3+T (same threshold/timing), the MAX6386XS23D3+T adds MR functionality and changes pinout - requiring PCB layout revision for replacement.