Analog Devices Inc./Maxim Integrated MAX6862UK225+T

Overview

The MAX6862UK225+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in a 5-pin SOT23 package, featuring a 2.235V factory-trimmed reset threshold, pin-selectable 10ms/150ms (min) reset timeout, active-high push-pull RESET output, manual reset input (MR), and no external components required. It monitors VCC for brownout detection and asserts reset during power-up, power-down, or software faults in ultra-low-power portable systems.

For engineers reviewing the MAX6862UK225+T datasheet, MAX6862UK225+T pinout, MAX6862UK225+T application, or MAX6862UK225+T equivalent, this device is selected for battery-powered medical monitors and handheld electronics where guaranteed reset validity down to VCC = +1.1V, 170nA typical supply current, and immunity to short VCC transients are critical design requirements.

Technical Context

The MAX6862UK225+T implements a precision voltage monitor with ±2.5% reset threshold accuracy over –40°C to +85°C, coupled with a CT pin that selects between two fixed reset timeout periods (D1: 10ms min or D3: 150ms min). Its active-high push-pull RESET output is referenced to VCC and guarantees VOH ≥ 0.8×VCC at ISOURCE = 500µA.

It includes an internal 10kΩ MR pullup resistor, supports MR pulse widths as short as 1µs, and provides 250ns MR-to-reset delay. The device operates across VCC = 1.2V to 5.5V and remains functional with reset assertion valid down to VCC = +1.1V - enabling robust operation in deep-brownout conditions.

Key Specifications

Pinout & Package

Package: 5-pin SOT23-5, lead-free, surface-mount. Compact footprint (2.9mm × 1.6mm × 1.1mm) suitable for space-constrained portable designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6862UK225+T, MAX6861UK225+T offers identical supervision functionality but requires µP-level logic inversion, while TPS3836K225DBVR trades timeout flexibility and ultra-low ICC for vendor consolidation - making MAX6862UK225+T optimal for designs needing both low power and configurable reset timing.

Availability

MAX6862UK225+T is available at Aetrix Electronics and suitable for glucose monitors, patient vital sign loggers, and handheld medical testers requiring stable component supply, long-lifecycle support, and lead-free compliance.

Supply support for MAX6862UK225+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 demanding industrial, medical, and communications applications.

The MAX68xx family delivers nanopower supervisory functions for battery-critical systems, emphasizing ultra-low ICC, guaranteed reset validity at low VCC, and minimal external component count.

FAQ

What is the exact reset threshold voltage of the MAX6862UK225+T?

The MAX6862UK225+T has a factory-trimmed reset threshold voltage of 2.235V, 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 "225" corresponds to VTH = 2.235V (min 2.180V, typ 2.235V, max 2.290V). The MAX6862UK225+T uses this precise threshold to reliably detect brownout on 2.2V nominal rails.

How does the CT pin configure the reset timeout period on the MAX6862UK225+T?

The CT pin on the MAX6862UK225+T selects between two minimum reset timeout periods: logic low (≤0.2×VCC) configures 10ms (min), and logic high (≥0.8×VCC) configures 150ms (min). These values are specified in Table 1 and validated in electrical characteristics (tRP = 150ms typ at D3 setting). The MAX6862UK225+T does not require external resistors or capacitors - CT is a direct logic interface.

What is the RESET output type and drive capability of the MAX6862UK225+T?

The MAX6862UK225+T features an active-high push-pull RESET output referenced to VCC. It guarantees VOH ≥ 0.8×VCC when sourcing 500µA (at VCC ≥ 2.38V) and VOL ≤ 0.3V when sinking 1.2mA (at VCC ≥ 2.38V). This eliminates external pullup components and ensures direct compatibility with standard CMOS µP reset inputs - a key feature distinguishing the MAX6862UK225+T from open-drain variants.

Does the MAX6862UK225+T include a watchdog timer function?

No, the MAX6862UK225+T does not include a watchdog timer. Per the Selector Guide and Pin Description sections, only MAX6864–MAX6869 variants include WDI functionality. The MAX6862UK225+T belongs to the MAX6861/MAX6862/MAX6863 subgroup, which provides MR input and CT-selectable timeout but no watchdog monitoring - confirmed by absence of WDI pin and watchdog timing specs in its parameter tables.

What is the minimum operating VCC for guaranteed reset assertion in the MAX6862UK225+T?

The MAX6862UK225+T guarantees valid RESET assertion down to VCC = +1.1V, as explicitly stated in the Features list and Electrical Characteristics table. This specification ensures deterministic reset behavior during deep brownout events - critical for medical safety compliance. Below 1.1V, RESET output may become indeterminate, but the MAX6862UK225+T remains functional and reasserts RESET immediately upon VCC recovery above threshold.