Analog Devices Inc./Maxim Integrated MAX6855UK17D3+T

Overview

The MAX6855UK17D3+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in 5-pin SOT23 package, featuring ultra-low 170nA typical supply current, factory-trimmed 1.665V reset threshold (suffix '17'), and 150ms minimum reset timeout (suffix 'D3'). 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 MAX6855UK17D3+T datasheet, MAX6855UK17D3+T pinout, MAX6855UK17D3+T application, or MAX6855UK17D3+T equivalent, this device serves as a precision voltage monitor and reset controller where low quiescent current, guaranteed reset validity down to VCC = 1.1V, and immunity to short VCC transients are critical selection criteria.

Technical Context

The MAX6855UK17D3+T integrates a precision voltage detector with ±2.5% threshold accuracy over temperature, a fixed 150ms (min) internal reset timeout timer, and an active-low manual reset input with 10kΩ internal pullup. Its push-pull active-high RESET output drives directly to VCC and remains asserted for the full timeout after VCC rises above 1.665V or MR deasserts.

No watchdog timer or CT pin is present - this variant belongs to the MAX6855 subgroup, confirmed by its pinout (Pin 1 = RESET active-high, Pin 3 = MR, Pin 4 = GND, Pin 5 = VCC) and absence of WDI/CT functionality per Selector Guide and Pin Description tables.

Key Specifications

Pinout & Package

MAX6855UK17D3+T is housed in a lead-free 5-pin SOT23-5 package (JEDEC MO-178AA), footprint-compatible with industry-standard SOT23 layouts and reflow-process ready.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3837K33DBVR and MAX6361KA29D3+T, the MAX6855UK17D3+T uniquely delivers sub-200nA current with active-high push-pull output and 1.665V threshold - enabling longest battery life and simplest µP interface in ultra-low-power medical sensors.

Availability

MAX6855UK17D3+T is available at Aetrix Electronics and suitable for portable glucose monitors, patient vital sign loggers, and low-power wearable sensors requiring stable component supply with long-lifecycle support.

Supply support for MAX6855UK17D3+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 connectivity in demanding industrial and medical applications.

The MAX6855UK17D3+T belongs to the nanopower µP supervisory family engineered specifically for battery-critical portable healthcare and handheld instrumentation where ultra-low ICC and guaranteed reset validity at low VCC are non-negotiable.

FAQ

What is the exact reset threshold voltage of the MAX6855UK17D3+T?

The MAX6855UK17D3+T has a factory-trimmed reset threshold voltage of 1.665V, with ±2.5% tolerance over the full –40°C to +85°C temperature range. This value is defined by the '17' suffix in the part number and confirmed in Table 2 (Threshold Suffix Guide) of the datasheet. The threshold is guaranteed to remain stable across voltage and temperature variations without external calibration.

Does the MAX6855UK17D3+T include a watchdog timer function?

No, the MAX6855UK17D3+T does not include a watchdog timer. It belongs to the MAX6855 subgroup, which provides only voltage monitoring and manual reset functionality. Watchdog capability is exclusive to MAX6864–MAX6869 variants (denoted by 'S' or 'L' suffixes). The MAX6855UK17D3+T pinout lacks WDI, and its functional diagram confirms absence of watchdog circuitry.

What is the RESET output configuration of the MAX6855UK17D3+T?

The MAX6855UK17D3+T features a push-pull active-high RESET output (Pin 1). When asserted, RESET goes high (to VCC); when deasserted, it goes low (to GND). This eliminates the need for an external pullup resistor and allows direct interfacing with microprocessors requiring active-high reset signals, such as many ARM Cortex-M series MCUs.

What is the minimum VCC voltage at which the MAX6855UK17D3+T guarantees valid reset operation?

The MAX6855UK17D3+T guarantees valid reset operation down to VCC = 1.1V, as explicitly stated in the Electrical Characteristics table under "Guaranteed Reset Valid to VCC = +1.1V". Below this voltage, the internal comparator may become indeterminate, but the device continues to assert RESET until VCC falls further - ensuring fail-safe behavior during deep brownout.

How is the 150ms reset timeout period implemented in the MAX6855UK17D3+T?

The 150ms minimum reset timeout period in the MAX6855UK17D3+T is implemented using an internal precision RC timer, fixed by the 'D3' suffix per Table 4 (Reset Timeout Periods). It begins timing when VCC rises above 1.665V or MR is deasserted, and holds RESET asserted for ≥150ms (typical 225ms, max 300ms) before deassertion - ensuring µP power rails stabilize fully before firmware execution resumes.