Analog Devices Inc./Maxim Integrated MAX6855UK17D6+T

Overview

The MAX6855UK17D6+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in a 5-pin SOT23 package, featuring ultra-low 170nA typical supply current, factory-trimmed 1.665V reset threshold (suffix "17"), and 600ms–1200ms minimum reset timeout (suffix "D6"). It provides active-high push-pull RESET output, manual reset input (MR), and operates across –40°C to +85°C for battery-powered medical and portable electronics.

For engineers reviewing the MAX6855UK17D6+T datasheet, MAX6855UK17D6+T pinout, MAX6855UK17D6+T application, or MAX6855UK17D6+T equivalent, this page delivers verified electrical parameters, exact pin functions, real-world use cases in glucose monitors and pagers, and two validated alternative parts with documented functional and timing differences.

Technical Context

This device integrates voltage monitoring, manual reset assertion, and reset timeout generation - but excludes watchdog timer and CT select functionality (confirmed by Selector Guide: MAX6855 supports MR and push-pull active-high RESET only). Its internal 10kΩ MR pullup, guaranteed RESET validity down to VCC = 1.1V, and immunity to ≤40µs VCC transients at 100mV overdrive define its robustness in brownout-prone systems.

The MAX6855UK17D6+T uses a precision bandgap reference for threshold stability (±2.5% over temperature), with reset hysteresis of 0.5% VTH. Its push-pull active-high RESET output sources ≥0.8×VCC at 500µA (VCC ≥ 2.38V), enabling direct interface to µP reset inputs without external components.

Key Specifications

Pinout & Package

Package: 5-pin SOT23-5 (lead-free, +T suffix), footprint-compatible with industry-standard 5-lead SOT-23 layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6855UK17D6+T, MAX6854UK17D6+T offers identical supervision accuracy and timing but requires external biasing for active-low logic, while TPS3837K33DBVR trades nanopower efficiency for lower unit cost in fixed 3.3V applications.

Availability

MAX6855UK17D6+T is available at Aetrix Electronics and suitable for glucose monitors, patient monitors, and portable audio devices requiring stable component supply, long-term lifecycle support, and lead-free compliance.

Supply support for MAX6855UK17D6+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 microprocessor supervision in battery-critical systems, emphasizing sub-µA ICC, factory-trimmed thresholds, and robust reset timing without external components.

FAQ

What is the exact reset threshold voltage of the MAX6855UK17D6+T?

The MAX6855UK17D6+T has a factory-trimmed reset threshold voltage of 1.665V (minimum 1.623V, maximum 1.707V) as defined by the "17" suffix in its ordering code. This value is guaranteed over the full –40°C to +85°C operating temperature range with ±2.5% tolerance, and applies specifically to the falling VCC condition that triggers reset assertion. The MAX6855UK17D6+T does not include hysteresis adjustment or user-programmable threshold selection.

Does the MAX6855UK17D6+T include a watchdog timer function?

No, the MAX6855UK17D6+T does not include a watchdog timer. Per the official Selector Guide and Pin Description tables, MAX6855 supports only voltage monitoring and manual reset (MR) functions, with no WDI pin or watchdog-related timing specifications. Watchdog capability is exclusive to MAX6864–MAX6869 variants, which feature dedicated WDI inputs and timeout options (S/L). The MAX6855UK17D6+T relies solely on VCC monitoring and MR assertion for reset generation.

What is the function of Pin 4 on the MAX6855UK17D6+T?

Pin 4 on the MAX6855UK17D6+T is a second ground (GND) terminal, electrically connected internally to Pin 2. Its inclusion improves noise immunity and thermal performance in high-density PCB layouts by providing an additional low-impedance return path. Unlike variants such as MAX6861/MAX6862, Pin 4 is not repurposed as CT or WDI - it serves exclusively as GND, consistent with the MAX6854/MAX6855/MAX6856 pinout configuration shown in the datasheet.

Can the MAX6855UK17D6+T operate with a 1.2V supply?

Yes, the MAX6855UK17D6+T is fully specified to operate with VCC as low as 1.2V, as confirmed in the Absolute Maximum Ratings and Electrical Characteristics tables. At 1.2V, it maintains valid reset assertion and deassertion behavior, though RESET output high-level voltage (VOH) drops to ≥0.8×VCC (≥0.96V) at 200µA source current. Its guaranteed reset validity down to VCC = 1.1V further ensures reliable operation during deep brownout conditions below nominal 1.2V.

What does the "D6" suffix indicate in MAX6855UK17D6+T?

The "D6" suffix in MAX6855UK17D6+T specifies the reset timeout period: D6 corresponds to a minimum reset timeout of 600ms, with typical 900ms and maximum 1200ms values (per Table 4). This timeout begins after VCC rises above the 1.665V threshold and MR is deasserted, ensuring sufficient hold time for microprocessor power-up sequencing. The D6 option is one of six fixed timeout choices available across the MAX685x family and is factory-set - not user-adjustable.