Analog Devices Inc./Maxim Integrated MAX6855UK30D4+T

Overview

The MAX6855UK30D4+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 3.000V reset threshold with 1200ms minimum reset timeout. It monitors VCC supply integrity, asserts reset during brownout or manual trigger, and guarantees valid reset down to VCC = +1.1V - ideal for battery-powered glucose monitors and portable medical devices.

For engineers reviewing the MAX6855UK30D4+T datasheet, MAX6855UK30D4+T pinout, MAX6855UK30D4+T application, or MAX6855UK30D4+T equivalent, this page delivers verified functional identity, exact pin roles, confirmed timing behavior, real-world use constraints, and validated alternative options - all grounded in Maxim's official datasheet Rev 4 (12/05).

Technical Context

The MAX6855UK30D4+T implements a precision voltage monitor with ±2.5% reset threshold accuracy over -40°C to +85°C, coupled with a fixed 1200ms reset timeout period after VCC recovery or MR deassertion. Its active-high push-pull RESET output is referenced to VCC and sinks ≤0.3V at 1.2mA load while sourcing ≥0.8×VCC at 500µA.

It includes an internally pulled-up MR input (10kΩ to VCC) with 250ns MR-to-reset delay and 1µs minimum pulse width support. Unlike watchdog-equipped variants (e.g., MAX6864–MAX6869), the MAX6855UK30D4+T omits WDI and CT pins - confirming it is a manual-reset-only supervisory device without watchdog or timeout-select functionality.

Key Specifications

Pinout & Package

Package: 5-pin SOT23-5, lead-free (RoHS-compliant), footprint-compatible with industry-standard 5-lead SOT-23.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3837K33DBVR and MAX6316LUK30D3+T, the MAX6855UK30D4+T uniquely delivers 3.0V threshold accuracy, 1200ms timeout, and integrated MR - making it the sole option for battery-powered medical devices requiring extended reset hold and user-triggered recovery.

Availability

MAX6855UK30D4+T is available at Aetrix Electronics and suitable for glucose monitoring systems, patient vital sign monitors, industrial handheld scanners, and low-power wireless sensors requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for MAX6855UK30D4+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) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, medical, and communications applications.

The MAX6855UK30D4+T belongs to Maxim's nanopower µP supervisory family, designed specifically for ultra-low-power, safety-critical portable electronics where guaranteed reset behavior under brownout and long-term battery operation are mandatory.

FAQ

What is the exact reset threshold voltage of the MAX6855UK30D4+T?

The MAX6855UK30D4+T has a factory-trimmed reset threshold of 3.000V with ±2.5% tolerance over -40°C to +85°C, as specified in Table 2 (Threshold Suffix Guide) of the datasheet. This value is confirmed by the "30" suffix in the part number and verified in Electrical Characteristics (VTH = 3.0V ±2.5%). The MAX6855UK30D4+T maintains this accuracy without external calibration.

Does the MAX6855UK30D4+T include a watchdog timer function?

No, the MAX6855UK30D4+T does not include a watchdog timer. Per the Selector Guide and Pin Description sections, only MAX6864–MAX6869 variants feature WDI input; the MAX6855UK30D4+T is a manual-reset-only supervisory circuit with MR input and no watchdog-related pins or timing circuitry.

What is the reset timeout period for the MAX6855UK30D4+T?

The MAX6855UK30D4+T has a fixed minimum reset timeout period of 1200ms, indicated by the "D4" suffix per Table 4 (Reset Timeout Periods). This duration is guaranteed after VCC rises above the 3.0V threshold or after MR is deasserted, ensuring sufficient time for power stabilization and µP initialization.

Is the MAX6855UK30D4+T pin-compatible with other MAX68xx supervisory ICs?

The MAX6855UK30D4+T shares the same 5-pin SOT23-5 package and pinout (RESET/MR/GND/GND/VCC) with MAX6854, MAX6856, MAX6858, and MAX6860 variants. However, output logic polarity differs: MAX6855UK30D4+T uses active-high push-pull, while MAX6854/MAX6856 use active-low outputs - requiring schematic review before substitution.

What is the maximum sink current capability of the MAX6855UK30D4+T RESET output?

The MAX6855UK30D4+T RESET output can sink up to 1.2mA while maintaining VOL ≤ 0.3V (at VCC ≥ 2.38V), as specified in the Electrical Characteristics table. This ensures robust drive strength into typical µP reset inputs with 10–100kΩ internal pull-downs, even at low VCC levels down to 1.2V.