Analog Devices Inc./Maxim Integrated MAX6414UK24

Overview

MAX6414UK24 from Maxim Integrated is a low-power, single-voltage microprocessor reset supervisor IC with factory-trimmed 2.4V VCC reset threshold, active-low open-drain RESET output, manual reset input (MR), and capacitor-adjustable reset timeout delay. It monitors supply voltage in battery-powered controllers and embedded systems, asserting reset during brownout or power-up until the external SRT capacitor discharges to 0.65V. Designed for operation from -40°C to +125°C, it guarantees valid reset logic down to VCC = 1V.

For engineers reviewing the MAX6414UK24 datasheet, MAX6414UK24 pinout, MAX6414UK24 application, or MAX6414UK24 equivalent, key selection criteria include its 2.4V ±2.5% reset threshold accuracy, 1.7µA typical quiescent current, open-drain output compatibility with mixed-supply µPs, and SOT23-5 package suitability for space-constrained portable equipment.

Technical Context

The MAX6414UK24 implements a precision bandgap-based voltage comparator for VCC monitoring and a 240nA constant-current ramp generator tied to the SRT pin to set reset timeout via external capacitor. Its internal 20kΩ pullup on MR enables standalone manual reset without external components.

Reset assertion occurs when VCC falls below 2.4V (±2.5% over temperature) or MR is pulled low; deassertion requires both VCC > 2.4V and MR high for the full timeout period determined by CSRT. The open-drain RESET output supports level-shifting up to 5.5V and sinks ≥50µA at 0.3V with VCC ≥1.8V.

Key Specifications

Pinout & Package

SOT23-5 package: ultra-compact 2.9mm × 1.6mm surface-mount footprint with 0.95mm pitch, optimized for high-density PCB layouts in portable and automotive electronics.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6414UK24, MAX6316LUK24D3+ offers simpler drive but sacrifices manual reset flexibility, while TPS3808G125DBVR matches open-drain functionality and current draw but omits MR-making MAX6414UK24 uniquely suited for battery-powered systems needing both low ICC and integrated manual reset.

Availability

MAX6414UK24 is available at Aetrix Electronics and suitable for battery-powered computers/controllers, automotive body electronics, and portable medical equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6414UK24 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 semiconductor company specializing in 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 space- and energy-constrained embedded systems where precision voltage monitoring and flexible timeout control are critical.

FAQ

What is the exact reset threshold voltage for MAX6414UK24 and how accurate is it over temperature?

The MAX6414UK24 has a factory-trimmed VCC reset threshold of 2.400V with ±2.5% accuracy guaranteed over the full -40°C to +125°C operating range. This specification is confirmed in the Electrical Characteristics table of the official datasheet (Rev 5, August 2012), where VTH min/max values are listed as 2.340V and 2.460V at TA = -40°C to +125°C. The 24 suffix in MAX6414UK24 directly maps to the 2.4V threshold per Table 1.

How do I calculate the SRT capacitor value needed for a 5ms reset timeout with MAX6414UK24?

To achieve a 5ms reset timeout with MAX6414UK24, use the formula tRP = (2.71 × 10⁶) × CSRT + 275µs. Rearranged: CSRT = (tRP − 275µs) / 2.71 × 10⁶. For tRP = 5ms (0.005s), CSRT = (0.005 − 0.000275) / 2,710,000 ≈ 1.745nF. A standard 1.8nF ceramic capacitor yields ~5.1ms timeout. The datasheet recommends low-leakage (<10nA) ceramic types for stability.

Does MAX6414UK24 support manual reset functionality, and what is the MR pin's electrical behavior?

Yes, MAX6414UK24 includes a dedicated MR (manual reset) input on pin 3. The MR pin is active-low with an internal 20kΩ pullup resistor to VCC, allowing it to be left unconnected if unused. When pulled to ≤0.8V (VIL), it asserts reset; reset remains active for the full timeout period after MR returns high. MR pulse width minimum is 1µs, and it rejects glitches <75ns-confirmed in the Electrical Characteristics table.

Can MAX6414UK24's open-drain RESET output interface with a 5V microcontroller while powered from a 3.3V supply?

Yes, MAX6414UK24's open-drain RESET output supports voltage levels up to 5.5V independent of VCC. When VCC = 3.3V, the RESET pin can safely sink current from a 5V pullup resistor connected to the µP's reset input. The datasheet explicitly states "RESET (Open-Drain) … -0.3V to +6.0V" in Absolute Maximum Ratings and shows this configuration in Figure 5, enabling seamless level translation without external components.

What is the minimum VCC voltage at which MAX6414UK24 guarantees valid RESET output behavior?

MAX6414UK24 guarantees valid RESET output behavior down to VCC = 1.0V, as stated in the Features list ("Guaranteed Reset Valid to VCC = 1V") and confirmed in the Electrical Characteristics table (VCC Supply Voltage Range: 1.0V to 5.5V). Below 1.0V, RESET sinking/sourcing capability degrades, but for most applications-where µPs cease operation below 1.0V-this guarantee ensures deterministic reset assertion during deep brownout events.