Analog Devices Inc./Maxim Integrated MAX6865UK16D5S+T

Overview

The MAX6865UK16D5S+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in 5-pin SOT23 package, featuring ultra-low 170nA typical supply current, factory-trimmed 1.575V reset threshold (suffix '16'), 600ms minimum reset timeout (suffix 'D5'), and integrated watchdog timer with 3.3s typical timeout (suffix 'S'). It monitors VCC, responds to manual reset (MR), and asserts active-high push-pull RESET during brownout, power-up, or watchdog expiry - used in battery-powered glucose monitors and portable medical devices.

For engineers reviewing the MAX6865UK16D5S+T datasheet, MAX6865UK16D5S+T pinout, MAX6865UK16D5S+T application, or MAX6865UK16D5S+T equivalent, this page delivers verified functional identity, exact pin roles, confirmed timing parameters, real-world use constraints, and validated alternative options for low-power µP reset supervision.

Technical Context

This device implements a precision voltage monitor with ±2.5% reset 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 >3.3s (typ). The internal reset timeout generator guarantees ≥600ms assertion after VCC recovery or MR release.

It features a dedicated MR input with 10kΩ internal pullup, 1µs minimum pulse width support, and 250ns MR-to-reset delay. RESET output is push-pull active-high, referenced to VCC, with VOH ≥0.8×VCC at ISOURCE = 500µA and VOL ≤0.3V at ISINK = 1.2mA - ensuring robust interfacing with modern low-voltage µPs.

Key Specifications

Pinout & Package

MAX6865UK16D5S+T is housed in a lead-free 5-pin SOT23-5 package (JEDEC MO-178AA), footprint-compatible with industry-standard 5-pin SOT23 layouts. Pin 1 is RESET (active-high push-pull), Pin 2 is GND, Pin 3 is MR (active-low manual reset), Pin 4 is WDI (watchdog input), and Pin 5 is VCC (supply voltage input).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3836K33DBVR and MAX6369KA29D3+T, the MAX6865UK16D5S+T uniquely combines ultra-low ICC, programmable 1.575V threshold, 600ms timeout, and integrated 3.3s watchdog - making it the sole option for long-life, low-VCC, safety-critical portable medical supervision.

Availability

MAX6865UK16D5S+T is available at Aetrix Electronics and suitable for glucose monitors, patient monitoring devices, MP3 players, and smart pagers requiring stable component supply across industrial temperature range (-40°C to +85°C) and long-lifecycle support.

Supply support for MAX6865UK16D5S+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 interface applications in demanding environments.

The MAX6865UK16D5S+T belongs to the MAX68xx nanopower supervisory family, engineered specifically for battery-constrained portable medical and consumer electronics requiring guaranteed reset behavior at sub-2V supply rails.

FAQ

What is the exact reset threshold voltage of the MAX6865UK16D5S+T?

The MAX6865UK16D5S+T has a factory-trimmed reset threshold of +1.575V, with ±2.5% tolerance over the full -40°C to +85°C temperature range. This value is defined by the '16' suffix in the part number and is confirmed in Table 2 (Threshold Suffix Guide) of the official datasheet. The threshold remains stable across voltage and temperature, enabling reliable brownout detection in low-voltage systems.

Does the MAX6865UK16D5S+T support active-high or active-low reset output?

The MAX6865UK16D5S+T provides an active-high push-pull RESET output (Pin 1), as confirmed by its placement in the MAX6865 row of the Selector Guide and its pin description stating "Active-High Push-Pull Reset Output". This eliminates need for external pullup resistors and directly interfaces with µP reset inputs expecting high-level assertion during fault conditions.

What is the watchdog timeout period for the MAX6865UK16D5S+T?

The MAX6865UK16D5S+T features a watchdog timeout period of 3.3s typical (minimum 1.5s, maximum 7.75s), indicated by the 'S' suffix in the part number and specified in Table 3 (Watchdog Timeout). The timer resets on any rising or falling edge at WDI (Pin 4) and expires only if WDI remains static beyond this window - providing robust runtime firmware supervision.

Can the MAX6865UK16D5S+T operate down to 1.2V supply voltage?

Yes, the MAX6865UK16D5S+T is fully specified to operate from VCC = 1.2V to 5.5V, as stated in the Absolute Maximum Ratings and Electrical Characteristics tables. Its reset output remains valid down to VCC = +1.1V, and supply current is characterized at 1.8V (170nA typ), confirming functional operation across the entire 1.2V–5.5V range.

Is the MAX6865UK16D5S+T pin-compatible with other MAX68xx devices?

The MAX6865UK16D5S+T uses the standard 5-pin SOT23-5 package with identical pinout to MAX6864/MAX6866 (RESET–GND–MR–WDI–VCC), as shown in the Pin Configurations diagram. However, it is not pin-compatible with MAX6861/MAX6862/MAX6863 (which use CT instead of WDI) or MAX6854/MAX6855/MAX6856 (which lack WDI), so PCB layout must match the MAX6865-specific assignment.