Analog Devices Inc./Maxim Integrated MAX6865UK17D4L+T

Overview

The MAX6865UK17D4L+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in a 5-pin SOT23 package, featuring ultra-low 170nA typical supply current, factory-trimmed 1.665V reset threshold (suffix "17"), 1200ms minimum reset timeout (suffix "D4"), and 209s typical watchdog timeout (suffix "L"). It integrates voltage monitoring, manual reset input (MR), and watchdog timer (WDI) to ensure reliable µP startup and fault recovery in battery-critical systems.

For engineers reviewing the MAX6865UK17D4L+T datasheet, MAX6865UK17D4L+T pinout, MAX6865UK17D4L+T application, or MAX6865UK17D4L+T equivalent, this device is selected for ultra-low-power brownout detection, manual system reset initiation, and long-interval watchdog supervision in portable medical and handheld electronics where VCC operation down to +1.1V and transient immunity are essential.

Technical Context

The MAX6865UK17D4L+T implements a precision bandgap-based voltage monitor with ±2.5% reset threshold accuracy over temperature, coupled with a digitally timed reset timeout generator (1200ms min) and a low-frequency RC-based watchdog timer (209s typ). Its MR input features internal 10kΩ pullup and 250ns MR-to-reset delay, while WDI accepts 150ns minimum pulses and clears the watchdog on any edge transition.

This device asserts an active-high push-pull RESET output when VCC falls below 1.665V, MR is pulled low, or the watchdog expires - holding RESET high for ≥1200ms after recovery. Guaranteed RESET validity to VCC = +1.1V and immunity to ≤40µs VCC transients at 100mV overdrive enable robust operation in noisy, low-voltage environments.

Key Specifications

Pinout & Package

Package: 5-pin SOT23-5, lead-free, surface-mount, footprint-compatible with industry-standard 5-lead SOT23.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6864UK17D4L+T and TPS3836K33DBVR, the MAX6865UK17D4L+T uniquely delivers active-high RESET, ultra-low 170nA current, and 209s watchdog in one 5-pin SOT23 - making it optimal for space-constrained, battery-sensitive medical devices requiring both precise brownout detection and long-interval runtime supervision.

Availability

MAX6865UK17D4L+T is available at Aetrix Electronics and suitable for glucose monitors, patient monitors, handheld medical testers, and industrial hand scanners requiring stable component supply across extended production lifecycles.

Supply support for MAX6865UK17D4L+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 power, sensing, and connectivity in demanding industrial, medical, and automotive applications.

The MAX6854–MAX6869 family was engineered specifically for nanopower microprocessor supervision in battery-operated medical and portable electronics, emphasizing ultra-low ICC, guaranteed low-VCC operation, and configurable watchdog timing.

FAQ

What is the exact reset threshold voltage of the MAX6865UK17D4L+T?

The MAX6865UK17D4L+T has a factory-trimmed reset threshold voltage of 1.665V, with ±2.5% accuracy over the full -40°C to +85°C temperature range. This value is defined by the "17" suffix per Maxim's Threshold Suffix Guide (Table 2), and is verified in the Electrical Characteristics table under VTH parameter. The device guarantees valid RESET assertion down to VCC = +1.1V, supporting robust operation during deep brownout conditions.

Does the MAX6865UK17D4L+T include a watchdog timer, and what is its timeout period?

Yes, the MAX6865UK17D4L+T includes a watchdog timer with a typical timeout period of 209 seconds, indicated by the "L" suffix in the part number. This long-interval watchdog is designed for firmware with extended idle or processing loops. The timer clears on any rising or falling edge at the WDI pin and triggers a reset if WDI remains static beyond the timeout - providing runtime supervision without requiring high-frequency toggling.

What type of RESET output does the MAX6865UK17D4L+T provide, and how is it configured?

The MAX6865UK17D4L+T provides an active-high push-pull RESET output, as confirmed by its pin configuration (Pin 1 = RESET, functional description states "Active-High Push-Pull Reset Output"). This eliminates the need for an external pullup resistor and directly interfaces with µPs that require an active-high reset signal. The output is referenced to VCC and sources/sinks sufficient current to drive standard CMOS reset inputs across the full operating voltage range.

What is the minimum reset timeout period for the MAX6865UK17D4L+T, and how is it set?

The MAX6865UK17D4L+T has a fixed minimum reset timeout period of 1200ms, specified by the "D4" suffix per Table 4 (Reset Timeout Periods). This timeout begins when VCC rises above the 1.665V threshold or MR is deasserted, and ensures the reset signal remains asserted long enough for complete µP and peripheral initialization. Unlike pin-selectable variants (e.g., MAX6861), this timeout is factory-programmed and not user-adjustable.

How does the MAX6865UK17D4L+T handle short VCC transients, and what is its immunity specification?

The MAX6865UK17D4L+T is immune to short VCC transients up to 40µs in duration when the overdrive is 100mV - as shown in the "Maximum VCC Transient Duration vs. Reset Threshold Overdrive" graph (Figure MAX684 toc05). This transient immunity prevents false resets caused by switching noise or load dumps. The device achieves this via internal filtering and hysteresis (0.5% of VTH), ensuring reliable operation in electrically noisy portable systems without external RC snubbers.