Analog Devices Inc./Maxim Integrated MAX6419UK44

Overview

MAX6419UK44 from Maxim Integrated is an active-high, push-pull microprocessor reset supervisor IC for dual-voltage monitoring systems. It features a factory-trimmed VCC reset threshold of 4.375V (±2.5%), an adjustable RESET IN input (1.26V threshold), capacitor-programmable reset timeout, and 1.7µA typical quiescent current. It operates across -40°C to +125°C and guarantees valid reset output down to VCC = 1V - used in automotive engine control units and battery-powered medical monitors.

For engineers reviewing the MAX6419UK44 datasheet, MAX6419UK44 pinout, MAX6419UK44 application, or MAX6419UK44 equivalent, this page delivers verified functional identity, exact SOT23-5 pin mapping, dual-threshold behavior, reset timeout calculation method, and two validated alternative parts with documented technical and application differences.

Technical Context

The MAX6419UK44 integrates two independent voltage monitoring paths: one fixed VCC comparator (4.375V ±2.5%) and one adjustable RESET IN comparator (1.26V reference, externally set via resistor divider). Reset assertion occurs if either input falls below its threshold or MR is pulled low.

Its reset timeout is determined by an internal 240nA current source charging an external capacitor (CSRT) to a 0.65V ramp threshold; deassertion occurs after CSRT reaches that voltage. The active-high push-pull RESET output drives high during normal operation and pulls low only during reset assertion.

Key Specifications

Pinout & Package

SOT23-5 package: 5-pin, surface-mount, lead-free or leaded options; footprint compatible with JEDEC MO-178AB standard.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6420UK44-T, MAX6419UK44 eliminates external pull-up components and simplifies layout; compared with TLV809E43DBVR, it adds critical dual-rail supervision, manual reset, and programmable timeout - making it suitable for complex embedded systems requiring design flexibility and safety redundancy.

Availability

MAX6419UK44 is available at Aetrix Electronics and suitable for automotive engine control units, portable medical equipment, and industrial PLC modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6419UK44 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, automotive, and medical applications.

The MAX6412–MAX6420 family was engineered specifically for low-power, dual-rail microprocessor supervision in harsh environments - emphasizing accuracy, temperature stability, and flexible timeout configuration without external logic.

FAQ

What is the exact VCC reset threshold voltage for MAX6419UK44?

The MAX6419UK44 has a factory-trimmed VCC reset threshold of 4.375V, with ±2.5% tolerance over -40°C to +125°C. This value corresponds to the "44" suffix per Table 1 in the datasheet and is laser-trimmed during production. The MAX6419UK44 uses this fixed threshold to supervise primary power rails such as 5V or 3.3V systems, while its RESET IN pin monitors secondary voltages independently.

How do I calculate the reset timeout period for MAX6419UK44?

The reset timeout period (tRP) for MAX6419UK44 is calculated using tRP = (2.71 × 10⁶) × CSRT + 275µs, where CSRT is the capacitor value in farads connected between SRT and GND. For example, a 1000pF capacitor yields ~2.985ms timeout. The internal 240nA current source charges CSRT to a 0.65V ramp threshold; the MAX6419UK44 guarantees this timing across temperature and voltage variations.

Does MAX6419UK44 support manual reset functionality?

Yes, MAX6419UK44 includes a dedicated MR (manual reset) pin (Pin 4) that asserts reset when pulled low. It features a 20kΩ internal pullup resistor, allowing direct connection of a momentary switch to ground without external components. Reset remains asserted for the full capacitor-programmed timeout after MR is released - a feature confirmed in the Pin Description and Detailed Description sections of the MAX6419UK44 datasheet.

Can MAX6419UK44 monitor a 1.8V rail? If so, how?

Yes, MAX6419UK44 can monitor a 1.8V rail using its RESET IN pin (Pin 3) and an external resistor divider. With a fixed 1.26V internal reference, set R2 = 1MΩ and calculate R1 = R2 × (1.8V / 1.26V − 1) ≈ 429kΩ. This configures the monitored threshold to 1.8V. The MAX6419UK44's high-impedance RESET IN input (10nA leakage) ensures minimal loading, preserving accuracy and battery life in portable applications.

What package type and footprint does MAX6419UK44 use?

MAX6419UK44 is supplied in a 5-pin SOT23-5 package (package code U5-2), compliant with JEDEC MO-178AB outline. Its land pattern (footprint) is documented as 90-0174 on maximintegrated.com/packages. The device is available in both leaded and lead-free versions - specify "+T" instead of "-T" in the order code for RoHS-compliant packaging. No alternate packages are offered for MAX6419UK44.