Analog Devices Inc./Maxim Integrated MAX6865UK23D2L+T

Overview

MAX6865UK23D2L+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in 5-pin SOT23 package, featuring ultra-low 170nA typical supply current, factory-trimmed 2.313V reset threshold, 40ms minimum reset timeout, and integrated watchdog timer with 209s typical timeout. It monitors VCC, responds to manual reset (MR), and asserts active-high push-pull RESET during brownout, power-up, or watchdog expiration - used in battery-powered glucose monitors and portable medical devices.

For engineers reviewing the MAX6865UK23D2L+T datasheet, MAX6865UK23D2L+T pinout, MAX6865UK23D2L+T application, or MAX6865UK23D2L+T equivalent, key selection criteria include its guaranteed reset validity down to VCC = +1.1V, immunity to short VCC transients (<40µs at 100mV overdrive), pin-selectable reset output type, and compatibility with low-voltage µP systems operating from 1.2V to 5.5V.

Technical Context

The MAX6865UK23D2L+T implements a precision bandgap-based voltage monitor with ±2.5% threshold accuracy over temperature, coupled with a digital watchdog timer that clears on any WDI edge and expires if WDI remains static beyond 209s (typ). Its internal 10kΩ MR pullup enables direct switch interface without external components.

Reset assertion is synchronized to VCC crossing the 2.313V threshold, with a fixed 40ms minimum timeout after VCC recovery and MR deassertion; the active-high push-pull RESET output drives directly to VCC with VOH ≥ 0.8×VCC at 500µA source current and VOL ≤ 0.3V at 1.2mA sink current.

Key Specifications

Pinout & Package

MAX6865UK23D2L+T is housed in a RoHS-compliant, lead-free 5-pin SOT23-5 package (2.9mm × 1.6mm × 1.1mm) with standard JEDEC MO-178 footprint and thermal pad omitted.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3837K33DBVR and STM6315SW13F, MAX6865UK23D2L+T uniquely combines 2.313V precision threshold, 40ms fast reset release, 209s watchdog, and 170nA ICC - making it optimal for compact, battery-constrained medical and portable electronics requiring both voltage and firmware integrity assurance.

Availability

MAX6865UK23D2L+T is available at Aetrix Electronics and suitable for glucose monitors, patient vital sign loggers, industrial handheld scanners, and low-power IoT edge nodes requiring stable component supply across automotive-grade temperature ranges and long-lifecycle deployments.

Supply support for MAX6865UK23D2L+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 communications markets.

The MAX6865UK23D2L+T belongs to the MAX68xx nanopower supervisory family, engineered specifically for ultra-low-power, space-constrained portable and medical electronics requiring simultaneous VCC monitoring, manual reset, and watchdog safety coverage.

FAQ

What is the exact reset threshold voltage of MAX6865UK23D2L+T?

The MAX6865UK23D2L+T has a factory-trimmed reset threshold of 2.313V, with ±2.5% tolerance over -40°C to +85°C. This value is encoded in the "23" suffix per Maxim's Threshold Suffix Guide (Table 2), and is verified in the Electrical Characteristics table under VTH parameter. The threshold remains stable across temperature, with normalized variation ≤±0.5% from -40°C to +85°C per Typical Operating Characteristics graph toc06.

Does MAX6865UK23D2L+T support active-high or active-low reset output?

MAX6865UK23D2L+T provides an active-high push-pull RESET output, as confirmed by its pin description (Pin 1 = RESET, "Active-High Push-Pull Reset Output") and Selector Guide entry. It drives high to VCC when asserted and low when deasserted, eliminating need for external pullup resistors and ensuring direct compatibility with µP reset inputs expecting high-active logic.

What is the watchdog timeout period for MAX6865UK23D2L+T?

The MAX6865UK23D2L+T features a watchdog timeout period of 209s typical (minimum 95s, maximum 487s), indicated by the "L" suffix in the part number. This is specified in Table 3 ("Watchdog Timeout") and confirmed in the Electrical Characteristics section under tWD parameter. The timer clears on any rising or falling edge at WDI and expires only if WDI remains static beyond this period.

Can MAX6865UK23D2L+T operate reliably below 1.8V supply?

Yes, MAX6865UK23D2L+T operates from VCC = 1.2V to 5.5V and guarantees valid reset assertion down to VCC = +1.1V, as stated in the Absolute Maximum Ratings and Electrical Characteristics tables. At 1.2V, supply current is 190nA typical, and RESET output maintains VOH ≥ 0.8×VCC and VOL ≤ 0.3V - enabling robust supervision in deep-brownout scenarios common in coin-cell-powered devices.

Is MAX6865UK23D2L+T pin-compatible with other MAX68xx variants?

MAX6865UK23D2L+T shares the same 5-pin SOT23-5 package and pinout (VCC, WDI, MR, GND, RESET) with MAX6864–MAX6866 and MAX6867–MAX6869 families, as shown in Pin Configurations and Selector Guide. However, it is not pin-compatible with MAX6854–MAX6856 (which lack WDI) or MAX6861–MAX6863 (which use CT instead of WDI), due to functional pin assignment differences.