Analog Devices Inc./Maxim Integrated MAX6865UK17D1L+T

Overview

The MAX6865UK17D1L+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in a 5-pin SOT23 package, combining voltage monitoring (1.665V factory-trimmed reset threshold), manual reset input (MR), and watchdog timer (209s typical timeout) with ultra-low 170nA typical supply current. It asserts an active-high push-pull RESET signal during VCC brownout, MR assertion, or watchdog timeout, maintaining reset for 10ms minimum after recovery - ideal for battery-powered glucose monitors and portable medical devices requiring long shelf life and reliable power-on reset.

For engineers reviewing the MAX6865UK17D1L+T datasheet, MAX6865UK17D1L+T pinout, MAX6865UK17D1L+T application, or MAX6865UK17D1L+T equivalent, key selection considerations include its 1.665V reset threshold tolerance (±2.5%), guaranteed RESET validity down to VCC = +1.1V, 209s watchdog timeout (L-suffix), and compatibility with noisy low-voltage systems where transient immunity and sub-µA quiescent current are critical.

Technical Context

This device implements a precision bandgap-based voltage monitor with 0.5% hysteresis, a digital watchdog timer cleared on WDI edge transitions, and a dedicated MR input with 250ns propagation delay and 1µs minimum pulse width. Its internal 10kΩ MR pullup eliminates external components while supporting CMOS-logic-level manual reset initiation.

The active-high push-pull RESET output delivers VOH ≥ 0.8×VCC at ISOURCE = 500µA (VCC ≥ 2.38V) and VOL ≤ 0.3V at ISINK = 1.2mA (VCC ≥ 2.38V), ensuring robust interfacing with µP reset inputs across 1.2V–5.5V supply range. Reset assertion is guaranteed valid down to VCC = +1.1V, enabling operation in deep brownout conditions.

Key Specifications

Pinout & Package

Package: 5-pin SOT23-5, lead-free, surface-mount.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6865UK17D1L+T, the MAX6864UK16D1L+T offers a lower reset threshold for tighter 1.65V rail monitoring, while the TPS3836K33DBVR provides fixed-threshold simplicity at the cost of 20× higher supply current and no watchdog - making MAX6865UK17D1L+T optimal for battery-critical medical and portable applications requiring both precision brownout detection and firmware supervision.

Availability

MAX6865UK17D1L+T is available at Aetrix Electronics and suitable for portable medical devices, battery-powered instrumentation, and low-power embedded controllers requiring stable component supply, long-term lifecycle support, and lead-free compliance.

Supply support for MAX6865UK17D1L+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 high-performance analog and mixed-signal ICs for power, sensing, and interface applications in industrial, medical, and consumer markets.

The MAX68xx family targets ultra-low-power microprocessor supervision, delivering nanopower operation, factory-trimmed thresholds, and integrated watchdog functionality for battery-constrained portable electronics.

FAQ

What is the exact reset threshold voltage of the MAX6865UK17D1L+T?

The MAX6865UK17D1L+T has a factory-trimmed reset threshold of 1.665V with ±2.5% tolerance over temperature (−40°C to +85°C). This value is confirmed in Table 2 (Threshold Suffix Guide) of the datasheet, where suffix "17" corresponds to 1.623V/1.665V/1.707V min/typ/max. The typical 1.665V threshold is optimized for monitoring 1.8V supply rails with adequate dropout margin.

Does the MAX6865UK17D1L+T support active-high or active-low reset output?

The MAX6865UK17D1L+T features an active-high push-pull RESET output, as confirmed by its pin description (Pin 1 = RESET, "Active-High Push-Pull Reset Output") and Selector Guide entry. This eliminates the need for an external pullup resistor and directly interfaces with µP reset pins expecting high-asserted reset signals, distinguishing it from open-drain or active-low variants in the MAX68xx family.

What is the watchdog timeout period for the MAX6865UK17D1L+T?

The MAX6865UK17D1L+T uses the "L" watchdog suffix, providing a typical timeout period of 209s (min 95s, max 487s) as specified in Table 3 (Watchdog Timeout). This long timeout is designed for firmware with extended idle or calibration phases, and the timer resets on any WDI edge - ensuring robust supervision without excessive interrupt overhead.

Can the MAX6865UK17D1L+T operate reliably below 1.8V supply?

Yes, the MAX6865UK17D1L+T operates from 1.2V to 5.5V and guarantees valid RESET assertion down to VCC = +1.1V, as stated in the Electrical Characteristics table. Its 170nA typical supply current and functional reset behavior at 1.2V make it suitable for single-cell Li-ion (2.5–4.2V) and NiMH (0.9–1.4V per cell) applications where supply voltage sags during peak load.

How does the manual reset (MR) input function on the MAX6865UK17D1L+T?

The MR input on the MAX6865UK17D1L+T is active-low with an internal 10kΩ pullup to VCC. Driving MR low for ≥1µs asserts RESET for the full 10ms timeout period, even after MR returns high. Glitch rejection is 200ns, and propagation delay (MR-to-RESET) is 250ns. Leaving MR unconnected defaults to high, disabling manual reset - no external components are needed.