Analog Devices Inc./Maxim Integrated MAX6865UK30D6S+T

Overview

MAX6865UK30D6S+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in 5-pin SOT23 package, featuring ultra-low 170nA typical supply current, factory-trimmed 3.000V reset threshold (±2.5%), 1200ms minimum reset timeout, manual reset input (MR), and watchdog timer with 209s typical timeout. It monitors VCC in battery-powered medical and portable electronics to ensure reliable µP initialization during brownout or software lockup.

For engineers reviewing the MAX6865UK30D6S+T datasheet, MAX6865UK30D6S+T pinout, MAX6865UK30D6S+T application, or MAX6865UK30D6S+T equivalent, this page delivers verified technical context, exact pin functions, real-world use cases, and validated alternative options for low-power system supervision.

Technical Context

The MAX6865UK30D6S+T integrates voltage monitoring, manual reset assertion, and watchdog timer functionality in a single BiCMOS IC. Its reset output remains asserted for ≥600ms after VCC rises above 3.000V and MR deasserts, and it guarantees valid reset operation down to VCC = +1.1V.

Watchdog timeout is fixed at 209s (typ) - selectable via 'L' suffix - and clears on any WDI edge, MR assertion, or RESET assertion. The device uses internal 10kΩ MR pullup and requires no external components beyond standard 0.1µF VCC bypass.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6864UK30D6S+T and TPS3836K33DBVR, the MAX6865UK30D6S+T uniquely combines active-high push-pull RESET, 3.000V precision threshold, 1200ms timeout, and 209s watchdog - enabling single-chip supervision for safety-critical, low-power medical devices without design compromises.

Availability

MAX6865UK30D6S+T is available at Aetrix Electronics and suitable for glucose monitors, patient vital sign recorders, industrial handheld scanners, and low-power wearable sensors requiring stable component supply across extended production lifecycles.

Supply support for MAX6865UK30D6S+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 was engineered specifically for ultra-low-power microprocessor supervision in battery-constrained portable and medical electronics, emphasizing nanoscale ICC, guaranteed low-VCC reset validity, and integrated watchdog reliability.

FAQ

What is the exact reset threshold voltage of the MAX6865UK30D6S+T?

The MAX6865UK30D6S+T has a factory-trimmed reset threshold of 3.000V with ±2.5% tolerance over -40°C to +85°C. This value is confirmed in Table 2 (Threshold Suffix Guide) of the datasheet, where suffix "30" corresponds to 3.000V nominal. The device guarantees valid reset assertion down to VCC = +1.1V, making it suitable for deep brownout detection in 3.0V systems.

Does the MAX6865UK30D6S+T support active-high reset output?

Yes, the MAX6865UK30D6S+T provides an active-high push-pull RESET output (Pin 1), as confirmed in the MAX6864/MAX6865/MAX6866 Pin Description section. Unlike open-drain variants, this output drives high without requiring an external pullup resistor and is referenced to VCC - directly compatible with µPs specifying active-high reset inputs.

What is the watchdog timeout period for the MAX6865UK30D6S+T?

The MAX6865UK30D6S+T features a watchdog timeout period of 209s typical (95s min, 487s max), designated by the "L" suffix in its part number. This long timeout is optimized for infrequent firmware health checks in low-duty-cycle devices like portable medical instruments, and the timer clears on any WDI edge, MR assertion, or RESET assertion.

How does the manual reset (MR) input function on the MAX6865UK30D6S+T?

The MR input (Pin 3) is active-low with internal 10kΩ pullup to VCC. Driving MR low for ≥1µs initiates a full reset cycle: RESET goes high and remains high for the full 600–1200ms timeout period, even after MR returns high. Glitch rejection is 200ns, and MR can be driven by CMOS logic or momentary switches without external debounce components.

Is the MAX6865UK30D6S+T pin-compatible with other devices in the MAX68xx family?

The MAX6865UK30D6S+T shares the same 5-pin SOT23-5 package and pinout (VCC, WDI, MR, GND, RESET) with MAX6864/MAX6866 variants. However, it is not pin-compatible with MAX6861–MAX6863 (which use CT pin) or MAX6854–MAX6856 (which lack WDI). Always verify pin function alignment using the Selector Guide before substitution.