Analog Devices Inc./Maxim Integrated MAX6865UK27D6L+T

Overview

The MAX6865UK27D6L+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in 5-pin SOT23 package, combining voltage monitoring (2.700V factory-trimmed reset threshold), manual reset input (MR), and watchdog timer (209s typical timeout) with 170nA typical supply current. It asserts an active-high push-pull RESET output during VCC brownout, MR assertion, or watchdog timeout, maintaining reset for 600–1200ms after recovery - ideal for battery-powered glucose monitors and portable medical devices.

For engineers reviewing the MAX6865UK27D6L+T datasheet, MAX6865UK27D6L+T pinout, MAX6865UK27D6L+T application, or MAX6865UK27D6L+T equivalent, key selection criteria include its ultra-low ICC (170nA typ), guaranteed RESET validity down to VCC = +1.1V, 209s watchdog timeout (L-suffix), and D6 reset timeout (600–1200ms), all in lead-free SOT23-5 packaging.

Technical Context

This device implements a precision bandgap-based voltage monitor with ±2.5% threshold accuracy over -40°C to +85°C, coupled with a digital watchdog timer that clears on any WDI edge (rising or falling) and expires if WDI remains static beyond 209s (typ). The internal reset timeout generator uses RC-based timing with temperature-compensated stability (±1% normalized tRP variation).

The MR input features 10kΩ internal pullup, 1µs minimum pulse width support, and 200ns glitch rejection; RESET output is push-pull active-high, referenced to VCC, with VOH ≥ 0.8×VCC (ISOURCE = 500µA) and VOL ≤ 0.3V (ISINK = 1.2mA at VCC ≥ 2.38V).

Key Specifications

Pinout & Package

Package: 5-pin SOT23-5, lead-free, surface-mount. Compact footprint (2.9mm × 1.6mm × 1.1mm) optimized for space-constrained portable designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6864UK27D6L+T, the MAX6865UK27D6L+T provides direct compatibility with active-high reset µPs without level-shifting; versus TPS3836K27DBVR, it delivers 15× lower ICC and critical watchdog functionality essential for autonomous medical firmware.

Availability

MAX6865UK27D6L+T is available at Aetrix Electronics and suitable for glucose monitors, patient loggers, smart hearing aids, wearable fall detectors, and portable diagnostic equipment requiring stable component supply across extended product lifecycles.

Supply support for MAX6865UK27D6L+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, mixed-signal, and power-management ICs for demanding industrial, medical, and communications applications.

The MAX68xx family delivers nanopower supervisory solutions targeting battery-operated medical and portable electronics, emphasizing ultra-low ICC, guaranteed brownout immunity, and integrated watchdog functionality in minimal footprints.

FAQ

What is the exact reset threshold voltage of the MAX6865UK27D6L+T?

The MAX6865UK27D6L+T has a factory-trimmed reset threshold voltage of 2.700V, with ±2.5% tolerance over the full -40°C to +85°C operating range. This value is confirmed in Table 2 (Threshold Suffix Guide) of the datasheet, where suffix "27" corresponds to 2.700V nominal. The MAX6865UK27D6L+T maintains this accuracy without external calibration.

Does the MAX6865UK27D6L+T support active-high reset output?

Yes, the MAX6865UK27D6L+T provides an active-high push-pull RESET output - confirmed in the Pin Description section (page 8) and Selector Guide (page 16). Unlike MAX6864 variants, the MAX6865UK27D6L+T drives RESET high during reset assertion and low when deasserted, eliminating need for external inverters in systems with active-high reset inputs.

What is the watchdog timeout period for the MAX6865UK27D6L+T?

The MAX6865UK27D6L+T features a watchdog timeout period of 209s typical (L-suffix), with min/max values of 95s and 487s respectively. This is specified in Table 3 (Watchdog Timeout) and applies across the full temperature range. The timer clears on any WDI edge and expires only if WDI remains static beyond this interval.

What reset timeout period does the "D6" suffix indicate in MAX6865UK27D6L+T?

The "D6" suffix in MAX6865UK27D6L+T specifies a minimum reset timeout period of 600ms, with typical and maximum values of 900ms and 1200ms respectively (Table 4). This duration ensures reliable µP and peripheral initialization after power recovery, MR assertion, or watchdog expiration - critical for complex boot sequences in medical firmware.

Is the MAX6865UK27D6L+T available in lead-free packaging?

Yes, the "+T" suffix in MAX6865UK27D6L+T explicitly denotes lead-free packaging per Maxim's ordering convention (Ordering Information, page 15). The device complies with RoHS requirements and uses matte-tin terminations on the 5-pin SOT23-5 package, suitable for standard Pb-free reflow profiles.