Analog Devices Inc./Maxim Integrated MAX6863UK26

Overview

The MAX6863UK26 from Maxim Integrated is a nanopower microprocessor supervisory circuit in a 5-pin SOT23 package, featuring pin-selectable 10ms/150ms reset timeout, active-low open-drain reset output, manual reset input (MR), and factory-trimmed 2.625V reset threshold (suffix "26"). It monitors VCC down to 1.1V, draws only 170nA typical supply current, and is used in battery-powered medical devices like glucose monitors to ensure reliable power-on reset and brownout protection.

For engineers reviewing the MAX6863UK26 datasheet, MAX6863UK26 pinout, MAX6863UK26 application, or MAX6863UK26 equivalent, this page delivers verified specifications, validated pin functions, confirmed timing behavior under VCC transients, and real-world substitution guidance for portable low-power embedded systems.

Technical Context

The MAX6863UK26 implements a voltage-monitoring comparator with 2.5% threshold hysteresis, a digital reset timeout generator with pin-selectable D1 (10ms min) or D3 (150ms min) delay, and an internally pulled-up MR input with 250ns assertion delay and 200ns glitch rejection. Its CT pin selects between two fixed timeout periods without external components.

It guarantees valid reset assertion down to VCC = 1.1V, exhibits immunity to VCC transients ≤40µs at 100mV overdrive, and supports noise-immune manual reset via a 10kΩ internal pullup - eliminating need for external debounce circuitry in handheld medical or portable instrumentation.

Key Specifications

Pinout & Package

Package: 5-pin SOT23-5 (lead-free compatible), footprint-compatible with TPS3836/TPS3837/TPS3838 series.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6863UK26, MAX6862UK26 trades level-shifting capability for simpler active-high drive, while TPS3836K26DBVR sacrifices nanopower operation and timeout flexibility for broader distributor availability and TI's long-term supply assurance.

Availability

MAX6863UK26 is available at Aetrix Electronics and suitable for glucose monitors, patient vital sign loggers, handheld diagnostic scanners, and wearable drug delivery pumps requiring stable component supply across extended production lifecycles.

Supply support for MAX6863UK26 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, medical, and communications applications.

The MAX6854–MAX6869 family was engineered specifically for ultra-low-power microprocessor supervision in battery-critical portable medical and instrumentation systems - prioritizing nanoscale ICC, robust VCC transient immunity, and hardware-configurable timing.

FAQ

What is the exact reset threshold voltage of MAX6863UK26?

The MAX6863UK26 has a factory-trimmed reset threshold of 2.625V, with ±2.5% tolerance over temperature (-40°C to +85°C). This value is defined by the "26" suffix per Maxim's Threshold Suffix Guide (Table 2), and is measured during VCC fall. The device guarantees valid reset assertion down to VCC = 1.1V, making it suitable for systems with steep brownout profiles.

How does the CT pin configure the reset timeout period on MAX6863UK26?

On the MAX6863UK26, the CT pin selects between two minimum reset timeout periods: connect CT to GND for 10ms (D1), or to VCC for 150ms (D3). This selection is sampled at reset deassertion and holds until the next reset event. The timing values are 10/15/25ms (min/typ/max) for D1 and 150/225/300ms for D3, per Table 1 and Table 4 in the datasheet.

What type of reset output does MAX6863UK26 provide, and how is it interfaced?

The MAX6863UK26 provides an active-low open-drain RESET output (Pin 4). It requires an external pullup resistor to the target µP's I/O voltage rail (e.g., 1.8V or 3.3V). This configuration enables level-shifting and avoids contention when multiple supervisors share a common reset bus. The output sinks ≥50µA with VOL ≤0.3V when asserted, per electrical characteristics at VCC ≥1.1V.

Does MAX6863UK26 include a watchdog timer function?

No, the MAX6863UK26 does not include a watchdog timer. It belongs to the MAX6861/MAX6862/MAX6863 subgroup, which features manual reset (MR) and pin-selectable reset timeout (CT) but omits WDI functionality. Watchdog capability is present only in MAX6864–MAX6869 variants (e.g., MAX6864UK26D3S), which add Pin 1 as WDI and support 3.3s or 209s timeout options.

Is MAX6863UK26 pin-compatible with other supervisory ICs?

Yes, the MAX6863UK26 is pin-compatible with the TPS3836/TPS3837/TPS3838 series from Texas Instruments in the SOT23-5 package. Pin mapping (CT=Pin1, GND=Pin2, MR=Pin3, RESET=Pin4, VCC=Pin5) matches exactly. However, functional differences exist - including lower ICC (170nA vs. ~1.2µA), pin-selectable timeout (vs. fixed), and different reset threshold tolerances - so electrical validation is required before drop-in replacement.