Analog Devices Inc./Maxim Integrated MAX6855UK35D5+T

Overview

The MAX6855UK35D5+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in a 5-pin SOT23 package, featuring active-high push-pull reset output, manual reset input (MR), and factory-trimmed 3.5V reset threshold (suffix "35"). It delivers ultra-low 170nA typical supply current, guarantees reset validity down to VCC = +1.1V, and provides a 300ms minimum reset timeout period (suffix "D5"). It is used in battery-powered medical devices like glucose monitors to ensure reliable power-on reset and brownout protection.

For engineers reviewing the MAX6855UK35D5+T datasheet, MAX6855UK35D5+T pinout, MAX6855UK35D5+T application, or MAX6855UK35D5+T equivalent, this page delivers verified functional identity, confirmed pin roles, exact reset timing behavior, and real-world design implications - not generic supervisory IC descriptions.

Technical Context

This device implements a voltage-monitoring supervisor with deterministic reset assertion on VCC drop below 3.5V ±2.5%, MR low pulse detection (≥1µs), and guaranteed reset deassertion after ≥300ms following VCC recovery and MR release. Its internal 10kΩ MR pullup and immunity to ≤40µs VCC transients at 100mV overdrive enable robust operation in noisy portable systems.

The MAX6855UK35D5+T uses BiCMOS process technology (2848 transistors) and operates across –40°C to +85°C. It asserts RESET high when VCC falls below threshold or MR is pulled low, and holds RESET high for ≥300ms after both conditions clear - critical for ensuring µP initialization stability during power-up sequencing.

Key Specifications

Pinout & Package

Package: 5-pin SOT23-5, lead-free (RoHS-compliant), surface-mount, footprint compatible with industry-standard 5-pin SOT23 layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3837K33DBVR and MAX6326UR29D3+T, the MAX6855UK35D5+T uniquely combines 3.5V precision threshold, active-high push-pull output, MR input, and 170nA current - making it optimal for space-constrained, battery-critical 3.3V medical and portable designs where simplicity and ultra-low power are non-negotiable.

Availability

MAX6855UK35D5+T is available at Aetrix Electronics and suitable for glucose monitors, patient monitors, and MP3 players requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6855UK35D5+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 industrial, medical, and consumer markets.

The MAX685x family targets ultra-low-power supervisory functions in battery-operated equipment, emphasizing nanoscale current consumption, factory-trimmed accuracy, and minimal external component count.

FAQ

What is the exact reset threshold voltage of the MAX6855UK35D5+T?

The MAX6855UK35D5+T has a factory-trimmed reset threshold of 3.500V with ±2.5% tolerance over –40°C to +85°C. This value is defined by the "35" suffix per Maxim's Threshold Suffix Guide (Table 2), and is validated across temperature and supply voltage ranges in the Electrical Characteristics table.

Does the MAX6855UK35D5+T include a watchdog timer?

No, the MAX6855UK35D5+T does not include a watchdog timer. Per the Selector Guide and Pin Configurations, only MAX6864–MAX6869 variants feature WDI input; the MAX6855UK35D5+T belongs to the MAX6854/MAX6855/MAX6856 group, which offers voltage monitoring and manual reset only.

What is the function of Pin 4 on the MAX6855UK35D5+T?

Pin 4 on the MAX6855UK35D5+T is a second GND terminal. As shown in the MAX6854/MAX6855/MAX6856 Pin Description and Top View diagram, Pins 2 and 4 are both labeled GND and must be connected to the same system ground potential to ensure thermal stability and minimize ground bounce during reset assertion.

Can the MAX6855UK35D5+T operate with VCC below 1.2V?

The MAX6855UK35D5+T guarantees functional operation down to VCC = +1.2V per Absolute Maximum Ratings and Electrical Characteristics tables. While reset output remains valid down to +1.1V, supply voltage below 1.2V is outside the specified operating range and may result in undefined behavior or failure to assert reset reliably.

What does the "D5" suffix indicate in MAX6855UK35D5+T?

The "D5" suffix in MAX6855UK35D5+T specifies the reset timeout period: D5 corresponds to a minimum 300ms timeout (with typical 450ms and maximum 600ms), as defined in Table 4 (Reset Timeout Periods) of the datasheet. This ensures sustained reset hold time for µP initialization sequences.