Analog Devices Inc./Maxim Integrated MAX6414UK27+

Overview

MAX6414UK27+ from Maxim Integrated is a low-power, single-voltage microprocessor reset supervisor IC with factory-trimmed 2.7V VCC reset threshold, active-low open-drain reset output, manual reset input (MR), and capacitor-adjustable reset timeout delay. It monitors supply voltage from 1.6V to 5V, asserts reset below threshold or on MR assertion, and holds reset for externally programmable duration after recovery - used in battery-powered controllers and embedded systems requiring reliable brownout protection.

For engineers reviewing the MAX6414UK27+ datasheet, MAX6414UK27+ pinout, MAX6414UK27+ application, or MAX6414UK27+ equivalent, key selection criteria include its 2.7V ±2.5% reset threshold accuracy over –40°C to +125°C, 1.7µA typical quiescent current, guaranteed RESET validity down to VCC = 1V, open-drain output compatibility with mixed-supply µPs, and SOT23-5 package suitability for space-constrained designs.

Technical Context

The MAX6414UK27+ implements a precision bandgap-based voltage comparator for VCC monitoring and a high-impedance manual reset input with internal 20kΩ pullup. Its reset timeout is set by an external capacitor connected to the SRT pin, charged by a 240nA current source to a 0.65V internal reference - enabling adjustable delays from 275µs (CSRT = 0) up to milliseconds.

It features power-supply transient immunity via built-in glitch rejection (75ns MR pulse rejection, immunity to ≤50µs VCC transients 100mV below threshold), guaranteed reset assertion during VCC ramp-down (tRD = 100µs), and valid logic-level output even at VCC = 1V - supporting robust operation across automotive and industrial temperature ranges.

Key Specifications

Pinout & Package

SOT23-5 package: 5-pin, surface-mount, lead-free (RoHS-compliant), 1.6mm × 2.9mm footprint, thermal pad optional, rated for –40°C to +125°C operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6414UK27+, MAX6316LUK27+T offers simpler drive but sacrifices MR functionality and increases supply current, while TPS3808G18DBVR reduces ICC and adds MR but removes timeout adjustability - making MAX6414UK27+ optimal for designs needing both manual reset and field-tunable reset duration.

Availability

MAX6414UK27+ is available at Aetrix Electronics and suitable for automotive body control modules, portable medical monitors, industrial PLC I/O submodules, and smart energy meters requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6414UK27+ 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) is a U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, automotive, and communications markets.

The MAX6412–MAX6420 product line delivers ultra-low-power, capacitor-programmable reset supervisors targeting battery-operated and thermally demanding applications where precision voltage monitoring and flexible timeout control are essential.

FAQ

What is the exact reset threshold voltage for MAX6414UK27+ and how is it trimmed?

The MAX6414UK27+ has a factory-trimmed VCC reset threshold of 2.700V (typical), with ±2.5% tolerance over –40°C to +125°C. This value is laser-trimmed during production using on-chip resistors, as confirmed in Table 1 of the datasheet (suffix "27" corresponds to 2.700V). No external components are needed to achieve this accuracy, and the threshold remains stable across temperature and supply variations.

Does MAX6414UK27+ support manual reset, and what are the electrical requirements for the MR pin?

Yes, MAX6414UK27+ includes a dedicated MR (manual reset) input. The MR pin has an internal 20kΩ pullup resistor, so it may be left floating if unused. To assert reset, pull MR low with a logic signal or momentary switch to ground. The minimum pulse width is 1µs, and it rejects glitches shorter than 75ns. MR-to-RESET propagation delay is 20ns, ensuring fast response to operator-initiated resets.

How do I calculate the reset timeout period for MAX6414UK27+ using the SRT capacitor?

The reset timeout period tRP (seconds) for MAX6414UK27+ is calculated as tRP = (2.71 × 10⁶) × CSRT + 275µs, where CSRT is the capacitor value in farads. For example, a 1500pF capacitor yields tRP ≈ 4.375ms. Use low-leakage ceramic capacitors (<10nA leakage), keep SRT traces short and away from noisy signals, and avoid probing SRT directly to prevent timeout errors.

Can MAX6414UK27+ operate reliably when VCC drops below 1.0V?

No - MAX6414UK27+ guarantees valid RESET output only down to VCC = 1.0V. Below this, output drive capability degrades significantly. For applications requiring reset assertion down to 0V, a 100kΩ pulldown resistor between RESET and GND is recommended (per Figure 6 in the datasheet) to ensure logic-low state. However, open-drain outputs like MAX6414UK27+ are not ideal for true 0V operation; consider push-pull alternatives if that requirement is strict.

What package type and RoHS status does MAX6414UK27+ use?

MAX6414UK27+ is supplied in a 5-pin SOT23-5 package (package code U5-2, outline 21-0057), with lead-free (RoHS-compliant) construction indicated by the "+" suffix. It measures 1.6mm × 2.9mm, supports reflow soldering at +260°C (lead-free), and is fully specified from –40°C to +125°C. Tape-and-reel packaging is standard, with minimum order quantity of 2500 pieces for this standard version.