Analog Devices Inc./Maxim Integrated MAX6863UK19+T

Overview

MAX6863UK19+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in 5-pin SOT23 package, featuring ultra-low 170nA typical supply current, factory-trimmed 1.9V reset threshold (±2.5%), and pin-selectable 10ms/150ms minimum reset timeout. It provides active-low open-drain RESET output, manual reset input (MR), and no external components required - designed for reliable power-on reset and brownout protection in battery-critical medical and portable systems.

For engineers reviewing the MAX6863UK19+T datasheet, MAX6863UK19+T pinout, MAX6863UK19+T application, or MAX6863UK19+T equivalent, key selection considerations include its 1.9V VTH tolerance over -40°C to +85°C, guaranteed RESET validity down to VCC = 1.1V, immunity to sub-40µs VCC transients, and CT pin-based timeout selection between 10ms and 150ms (min).

Technical Context

The MAX6863UK19+T implements a precision voltage monitor with hysteresis (0.5% of VTH) and a dual-mode reset timeout generator controlled by the CT pin: low = D1 (10ms min), high = D3 (150ms min). Its internal 10kΩ MR pullup enables direct switch interfacing without external biasing.

This device belongs to the MAX6861–MAX6863 subgroup, which excludes watchdog functionality but adds CT-based timeout flexibility - distinguishing it from MAX6864–MAX6869 (watchdog-enabled) and MAX6854–MAX6856 (fixed timeout only). All variants share identical 5-pin SOT23 layout and operate across 1.2V–5.5V VCC.

Key Specifications

Pinout & Package

MAX6863UK19+T uses a standard 5-pin SOT23 package (2.9mm × 1.6mm × 1.1mm), RoHS-compliant and lead-free (+T suffix). Pin 1 is marked with a dot; pin numbering follows standard SOT23 orientation (counterclockwise from mark).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6863UK19+T, MAX6861UK19+T offers identical supervision accuracy and timeout flexibility but trades open-drain versatility for lower output impedance, while TPS3836K33DBVR sacrifices nanopower operation and threshold adjustability for TI's broad distribution and automotive qualification.

Availability

MAX6863UK19+T is available at Aetrix Electronics and suitable for glucose monitors, patient vital sign recorders, and wireless medical telemetry units requiring stable component supply with long-term lifecycle support.

Supply support for MAX6863UK19+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, mixed-signal, and power management ICs for demanding industrial, medical, and communications applications.

The MAX6861–MAX6863 family delivers nanopower supervisory functionality with pin-selectable timing - engineered specifically for ultra-low-power portable medical and battery-constrained IoT endpoints.

FAQ

What is the exact reset threshold voltage of MAX6863UK19+T?

The MAX6863UK19+T has a factory-trimmed reset threshold of 1.9V with ±2.5% tolerance over -40°C to +85°C. This value is confirmed in Table 2 (Threshold Suffix Guide) of the datasheet, where suffix "19" corresponds to 1.853V (min), 1.900V (typ), and 1.948V (max). The device guarantees valid reset assertion down to VCC = 1.1V, making it suitable for deep brownout detection in low-voltage systems.

How does the CT pin configure reset timeout on MAX6863UK19+T?

On MAX6863UK19+T, the CT pin selects between two minimum reset timeout periods: connect CT to GND (logic low) for 10ms (D1), or to VCC (logic high) for 150ms (D3). These values are specified in Table 1 and Figure 1. The timeout begins after VCC rises above VTH or MR deasserts, and the CT state is sampled at timeout initiation - changes during an active timeout do not take effect until the next reset event.

Does MAX6863UK19+T include a watchdog timer?

No, MAX6863UK19+T does not include a watchdog timer. It belongs to the MAX6861–MAX6863 subgroup, which provides manual reset (MR) and CT-selectable timeout but omits WDI functionality. Watchdog capability is exclusive to MAX6864–MAX6869 variants (e.g., MAX6864UK19D3S). Using MAX6863UK19+T requires external software or hardware watchdog implementation if code-execution monitoring is required.

What is the RESET output type of MAX6863UK19+T and how should it be connected?

MAX6863UK19+T features an active-low open-drain RESET output (Pin 4). It requires an external pullup resistor to a valid logic rail - typically to the µP's VDD (e.g., 1.8V, 3.3V, or 5V) - enabling level-shifting across supply domains. Unlike push-pull outputs, this configuration avoids contention when multiple devices drive the same reset bus and supports wired-OR architectures common in complex embedded systems.

Can MAX6863UK19+T operate with supply voltages below 1.8V?

Yes, MAX6863UK19+T operates across VCC = 1.2V to 5.5V and guarantees RESET validity down to VCC = 1.1V. Electrical Characteristics confirm functional operation at 1.2V (minimum), with typical supply current of 170nA at 1.8V and 190nA at 1.2V. This makes it suitable for single-cell LiFePO₄ (2.5–3.6V) or alkaline (0.9–1.5V per cell) systems where brownout detection must occur near end-of-life voltage.