Analog Devices Inc./Maxim Integrated MAX6865UK30D5S+T

Overview

The MAX6865UK30D5S+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in a 5-pin SOT23 package, featuring ultra-low 170nA typical supply current, factory-trimmed 3.000V reset threshold (suffix "30"), 300ms minimum reset timeout (suffix "D5"), and 3.3s typical watchdog timeout (suffix "S"). It monitors VCC, responds to manual reset (MR) input, and triggers reset on watchdog timer expiration - designed for battery-critical portable medical and consumer devices.

For engineers reviewing the MAX6865UK30D5S+T datasheet, MAX6865UK30D5S+T pinout, MAX6865UK30D5S+T application, or MAX6865UK30D5S+T equivalent, key selection criteria include its active-high push-pull RESET output, guaranteed reset validity down to VCC = +1.1V, immunity to short VCC transients (<40µs at 100mV overdrive), and compatibility with 1.2V–5.5V supply rails.

Technical Context

The MAX6865UK30D5S+T integrates a precision voltage monitor, manual reset input (MR), and watchdog timer with 3.3s typical timeout (S-suffix). Its internal architecture asserts reset when VCC falls below 3.000V, MR is pulled low, or WDI remains static beyond the watchdog period - with reset held for 300ms after recovery.

It uses BiCMOS process technology (2848 transistors), supports CMOS-level MR/WDI inputs with 10kΩ internal MR pullup, and guarantees valid reset operation across –40°C to +85°C while consuming only 170nA at 2.5V/25°C - enabling multi-year operation on coin-cell batteries.

Key Specifications

Pinout & Package

Package: 5-pin SOT23-5, lead-free, surface-mount. Compact 2.9mm × 1.6mm footprint with 0.95mm height - optimized for space-constrained portable PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6864UK30D5S+T, the MAX6865UK30D5S+T provides active-high reset compatibility without external inverters; versus TPS3836K33DBVR, it delivers 10× lower supply current and integrated watchdog - critical for long-life portable medical designs.

Availability

MAX6865UK30D5S+T is available at Aetrix Electronics and suitable for portable medical devices, battery-powered wearables, and industrial handheld instruments requiring stable component supply across extended product lifecycles.

Supply support for MAX6865UK30D5S+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 MAX6865UK30D5S+T belongs to the MAX6854–MAX6869 nanopower supervisory family, engineered specifically for ultra-low-power, space-constrained portable electronics where battery longevity and reliability are paramount.

FAQ

What is the exact reset threshold voltage of the MAX6865UK30D5S+T?

The MAX6865UK30D5S+T has a factory-trimmed reset threshold of 3.000V 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 "30" corresponds to VTH = 3.000V. The device guarantees reset assertion when VCC falls below this threshold and holds reset for 300ms after VCC rises above it.

Does the MAX6865UK30D5S+T require external components for basic operation?

No, the MAX6865UK30D5S+T operates autonomously with no external components required. It includes an internal 10kΩ pullup on MR, needs only a 0.1µF bypass capacitor on VCC (recommended for noise immunity), and its active-high push-pull RESET output eliminates external pullup resistors. The watchdog timer and reset timeout are fully internal and factory-configured.

How does the watchdog timer in the MAX6865UK30D5S+T respond to signal edges?

The MAX6865UK30D5S+T watchdog timer clears on any rising or falling edge at the WDI pin - not just toggles - and detects pulses as short as 150ns. If WDI remains static (high or low) longer than the 3.3s typical timeout, the timer expires and triggers a 300ms reset pulse. The timer also resets automatically when MR is asserted or RESET is active.

What is the minimum supply voltage at which the MAX6865UK30D5S+T guarantees valid reset output?

The MAX6865UK30D5S+T guarantees valid reset output down to VCC = +1.1V across the full temperature range (–40°C to +85°C). Below this voltage, RESET may become indeterminate. For applications requiring valid reset down to 0V, a 2MΩ pulldown resistor between RESET and GND is recommended per Figure 5 in the datasheet.

Is the MAX6865UK30D5S+T pin-compatible with other devices in the MAX68xx family?

Yes, the MAX6865UK30D5S+T shares the same 5-pin SOT23-5 package and pinout (VCC, WDI, MR, GND, RESET) with all MAX6864–MAX6869 variants. However, RESET polarity differs: MAX6865 offers active-high push-pull, while MAX6864 offers active-low. Swapping requires verification of host µP reset input logic level and no hardware changes beyond that polarity match.