Analog Devices Inc./Maxim Integrated MAX6855UK46D2+T

Overview

MAX6855UK46D2+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in 5-pin SOT23 package, featuring active-high push-pull reset output, 4.625V factory-trimmed reset threshold (±2.5%), 40ms minimum reset timeout, and manual reset input. It monitors VCC supply integrity and asserts reset during power-up, brownout, or operator-initiated recovery in ultra-low-power portable systems.

For engineers reviewing the MAX6855UK46D2+T datasheet, MAX6855UK46D2+T pinout, MAX6855UK46D2+T application, or MAX6855UK46D2+T equivalent, this device serves as a precision voltage monitor with deterministic reset timing, low-glitch immunity, and guaranteed reset validity down to VCC = +1.1V - critical for battery-powered medical and handheld electronics.

Technical Context

The MAX6855UK46D2+T implements a precision bandgap-based voltage reference and comparator to detect VCC falling below its 4.625V threshold, triggering an active-high push-pull RESET signal. Its internal timer enforces a fixed 40ms minimum reset assertion period after VCC recovers and MR deasserts.

It includes a 10kΩ internal pullup on the MR pin, supports CMOS-logic-level manual reset inputs, and rejects transients ≤40µs at 100mV overdrive. No external components are required beyond standard 0.1µF VCC bypass capacitance.

Key Specifications

Pinout & Package

MAX6855UK46D2+T is housed in a lead-free 5-pin SOT23-5 package (2.9mm × 1.6mm × 1.1mm), optimized for space-constrained portable PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3836K33DBVR and ADM6806-46ARTZ-R7, the MAX6855UK46D2+T uniquely delivers 4.625V precision, active-high push-pull output, and nanopower 170nA consumption - making it optimal for new designs targeting battery longevity and simplified µP interface.

Availability

MAX6855UK46D2+T is available at Aetrix Electronics and suitable for portable medical devices, wearable health monitors, industrial handheld terminals, and low-power IoT sensors requiring stable component supply across extended production lifecycles.

Supply support for MAX6855UK46D2+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 demanding industrial, medical, and communications applications.

The MAX685x family targets ultra-low-power microprocessor supervision in battery-critical systems, emphasizing nanoscale current draw, factory-trimmed accuracy, and robust transient immunity without external components.

FAQ

What is the exact reset threshold voltage of the MAX6855UK46D2+T?

The MAX6855UK46D2+T has a factory-trimmed reset threshold voltage of 4.625V, with tolerance of ±2.5% over the full operating temperature range (-40°C to +85°C). This value is confirmed in Table 2 (Threshold Suffix Guide) of the datasheet, where suffix "46" corresponds to 4.625V nominal. The MAX6855UK46D2+T maintains this accuracy without calibration or external components.

Does the MAX6855UK46D2+T include a watchdog timer function?

No, the MAX6855UK46D2+T does not include a watchdog timer. It belongs to the MAX6854/MAX6855/MAX6856 subgroup, which provides only voltage monitoring and manual reset functionality. Watchdog capability is exclusive to MAX6864–MAX6869 variants (e.g., MAX6864UK46D2S+T), as clearly defined in the Selector Guide and Pin Description sections of the datasheet.

What is the reset output configuration of the MAX6855UK46D2+T?

The MAX6855UK46D2+T features an active-high push-pull reset output on Pin 1. Unlike open-drain or active-low variants, this configuration drives the RESET pin high during reset assertion and low otherwise, eliminating the need for an external pullup resistor and enabling direct interface with µPs requiring active-high reset signals.

What is the minimum reset timeout period for the MAX6855UK46D2+T?

The MAX6855UK46D2+T has a minimum reset timeout period of 40ms, corresponding to timeout option "D2" per Table 4 (Reset Timeout Periods). This value is guaranteed across temperature and supply voltage (VCC ≥ 1.2V), ensuring sufficient time for microcontroller initialization and peripheral stabilization before release.

Is the MAX6855UK46D2+T compatible with 1.8V supply systems?

Yes, the MAX6855UK46D2+T operates over a VCC range of 1.2V to 5.5V and guarantees valid reset output down to VCC = +1.1V. At 1.8V supply, its typical supply current is 170nA, and RESET output high-level voltage meets VOH ≥ 0.8 × VCC with 200µA source current - fully compatible with 1.8V logic families.