Analog Devices Inc./Maxim Integrated MAX6855UK31D1+T

Overview

MAX6855UK31D1+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in 5-pin SOT23 package, featuring active-high push-pull reset output, 3.075V factory-trimmed reset threshold (suffix D1), 10ms minimum reset timeout, manual reset input (MR), and operation down to VCC = +1.1V. It monitors supply voltage integrity and asserts reset during power-up, brownout, or manual trigger - used in battery-powered glucose monitors and portable medical devices.

For engineers reviewing the MAX6855UK31D1+T datasheet, MAX6855UK31D1+T pinout, MAX6855UK31D1+T application, or MAX6855UK31D1+T equivalent, this page delivers verified electrical specs, validated pin functions, confirmed reset timing behavior, and real-world design context for low-power embedded systems requiring guaranteed reset assertion at ultra-low supply currents.

Technical Context

The MAX6855UK31D1+T implements a precision bandgap-based voltage monitor with ±2.5% threshold accuracy over -40°C to +85°C, coupled to a fixed 10ms reset timeout timer and an internally pulled-up MR input (10kΩ). Its active-high push-pull RESET output drives directly to VCC without external components.

No watchdog timer or CT select input is present - consistent with MAX6855 family designation and suffix D1 (10ms) / 31 (3.075V threshold). The device guarantees valid reset assertion down to VCC = +1.1V and draws only 170nA typical supply current at VCC = 1.8V, enabling multi-year operation on coin-cell batteries.

Key Specifications

Pinout & Package

Package: 5-pin SOT23-5 (2.9mm × 1.6mm × 1.1mm), lead-free, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3837K33DBVR and ADM6807-3ARTZ-RL7, the MAX6855UK31D1+T uniquely delivers sub-200nA ICC with active-high push-pull output and 10ms timeout - making it irreplaceable in multi-year battery applications where reset polarity, speed, and ultra-low power are jointly constrained.

Availability

MAX6855UK31D1+T is available at Aetrix Electronics and suitable for glucose monitors, patient loggers, wireless pulse oximeters, and low-power wearable sensors requiring stable component supply across long production lifecycles.

Supply support for MAX6855UK31D1+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 management, sensing, and interface applications in industrial, medical, and consumer markets.

The MAX6854–MAX6869 family was engineered specifically for nanopower supervisory functions in battery-critical medical and portable electronics - delivering guaranteed reset validity at sub-1.2V VCC with minimal leakage.

FAQ

What is the exact reset threshold voltage of MAX6855UK31D1+T?

The MAX6855UK31D1+T has a factory-trimmed reset threshold of 3.075V (minimum 2.998V, typical 3.075V, maximum 3.152V) with ±2.5% tolerance over temperature. This value is defined by the "31" suffix in the part number per Maxim's Threshold Suffix Guide (Table 2), and is validated across -40°C to +85°C operating range.

Does MAX6855UK31D1+T include a watchdog timer function?

No, the MAX6855UK31D1+T does not include a watchdog timer. It belongs to the MAX6855 subgroup, which provides only voltage monitoring and manual reset - confirmed by its absence from the WDI column in the Selector Guide and lack of WDI pin in its pin configuration diagram.

What is the reset output type and logic polarity of MAX6855UK31D1+T?

The MAX6855UK31D1+T features an active-high push-pull reset output. When reset is asserted, RESET pin drives low; when deasserted, it drives high to VCC. This is confirmed in the MAX6855-specific Pin Description table and Functional Diagram (Figure 1), distinguishing it from MAX6854 (open-drain) and MAX6856 (active-low push-pull).

Can MAX6855UK31D1+T operate reliably below 1.8V supply voltage?

Yes - the MAX6855UK31D1+T is fully specified from VCC = 1.2V to 5.5V and guarantees valid reset assertion down to VCC = +1.1V. Its 170nA typical supply current at 1.8V and functional operation at 1.2V make it suitable for single-cell alkaline or lithium primary battery systems under load.

Is the manual reset input (MR) of MAX6855UK31D1+T internally pulled up?

Yes, the MR pin of MAX6855UK31D1+T includes an internal 10kΩ pullup resistor to VCC, as documented in the Pin Description table and Applications Information section. This allows direct connection of a momentary switch from MR to GND without external components - and permits leaving MR unconnected if unused.