Analog Devices Inc./Maxim Integrated MAX6865UK16D5L+T

Overview

The MAX6865UK16D5L+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in 5-pin SOT23 package, combining voltage monitoring (1.575V reset threshold), manual reset input (MR), and watchdog timer (209s typical timeout) with ultra-low 170nA supply current. It asserts an active-high push-pull RESET signal during VCC brownout, MR assertion, or watchdog timeout, and holds reset for 600ms minimum after recovery - ideal for battery-powered glucose monitors and portable medical devices.

For engineers reviewing the MAX6865UK16D5L+T datasheet, MAX6865UK16D5L+T pinout, MAX6865UK16D5L+T application, or MAX6865UK16D5L+T equivalent, key selection criteria include its factory-trimmed 1.575V reset threshold, 209s watchdog timeout (L-suffix), 600ms reset timeout (D5), active-high push-pull output, and guaranteed reset validity down to VCC = +1.1V.

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 and expires if WDI remains static beyond 209s (typ). The internal reset timeout generator uses a temperature-stable RC oscillator with <±10% variation across temperature.

The MR input features 10kΩ internal pullup, 1µs minimum pulse width support, and 200ns glitch rejection; RESET output delivers VOH ≥ 0.8×VCC at 500µA source current and VOL ≤ 0.3V at 1.2mA sink - compatible with 1.2V–5.5V logic domains without level-shifting.

Key Specifications

Pinout & Package

Package: 5-pin SOT23-5 (lead-free, +T suffix), 2.9mm × 1.6mm footprint, 1.1mm height - compatible with high-density portable PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6864UK16D5L+T and TPS3836K33DBVR, the MAX6865UK16D5L+T uniquely combines ultra-low 170nA current, 1.575V threshold, active-high RESET, and 209s watchdog - enabling longer battery life and broader voltage compatibility in portable medical and wearable systems.

Availability

MAX6865UK16D5L+T is available at Aetrix Electronics and suitable for glucose monitors, patient monitors, MP3 players, and smart wearables requiring stable component supply with long-term lifecycle support.

Supply support for MAX6865UK16D5L+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 MAX6854–MAX6869 family delivers nanopower supervision for battery-critical systems, with emphasis on ultra-low ICC, wide VCC range, and integrated watchdog functionality - targeting portable healthcare and consumer electronics.

FAQ

What is the reset threshold voltage of the MAX6865UK16D5L+T?

The MAX6865UK16D5L+T has a factory-trimmed reset threshold of 1.575V, with ±2.5% tolerance over -40°C to +85°C. This value is encoded in the "16" suffix per Maxim's Threshold Suffix Guide (Table 2), making it suitable for monitoring 1.8V supplies where brownout detection must occur before LDO dropout. The MAX6865UK16D5L+T guarantees valid reset assertion down to VCC = +1.1V.

Does the MAX6865UK16D5L+T include a watchdog timer, and what is its timeout period?

Yes, the MAX6865UK16D5L+T includes a watchdog timer with a typical timeout period of 209s, indicated by the "L" suffix in the part number. The timer clears on any rising or falling edge at the WDI pin and expires only if WDI remains static beyond this period. This long timeout supports firmware operations like sensor calibration or wireless firmware updates without triggering spurious resets.

What type of reset output does the MAX6865UK16D5L+T provide?

The MAX6865UK16D5L+T provides an active-high push-pull reset output on Pin 1. Unlike open-drain variants, it does not require an external pullup resistor. It sources up to 500µA while deasserted (VOH ≥ 0.8×VCC) and sinks up to 1.2mA while asserted (VOL ≤ 0.3V), ensuring robust interfacing with modern µP reset inputs across 1.2V–5.5V supply ranges.

How is the reset timeout period configured on the MAX6865UK16D5L+T?

The reset timeout period is factory-configured and fixed at 600ms (minimum), denoted by the "D5" suffix. This value is selected from Table 4 (Reset Timeout Periods) and cannot be adjusted externally. The 600ms duration ensures sufficient hold time for complete µP initialization, including PLL lock, memory self-test, and peripheral configuration sequences.

What is the supply current consumption of the MAX6865UK16D5L+T under typical operating conditions?

The MAX6865UK16D5L+T consumes just 170nA typical supply current at +25°C with VCC = 2.5V and no reset asserted - confirmed in the Electrical Characteristics table. This ultra-low ICC enables multi-year operation on standard coin-cell batteries (e.g., CR2032) in always-on portable medical devices, with minimal impact on shelf life or runtime.