Analog Devices Inc./Maxim Integrated MAX6424UK46+T

Overview

The MAX6424UK46+T from Analog Devices is a low-power microprocessor supervisor IC with active-low push-pull reset output, 4.625V ±1.5% factory-trimmed reset threshold, capacitor-adjustable reset timeout (3.0–5.75ms with 1500pF), and guaranteed operation down to VCC = 1V. It monitors system supply voltage in portable, battery-powered, and automotive controllers to prevent erroneous code execution during power-up, brownout, or power-down.

For engineers reviewing the MAX6424UK46+T datasheet, MAX6424UK46+T pinout, MAX6424UK46+T application, or MAX6424UK46+T equivalent, key selection criteria include its SOT23-5 package, 1.6µA typical quiescent current, open-drain compatibility via logic-level flexibility, immunity to short VCC transients (<50µs at 100mV overdrive), and precise 0.65V internal ramp reference for timeout control.

Technical Context

This device implements a precision voltage-detection architecture using laser-trimmed resistors to set the 4.625V reset threshold with ±1.5% accuracy at +25°C and ±2.5% over –40°C to +125°C. A 240nA internal current source charges an external capacitor on the SRT pin to generate a programmable reset timeout period.

The push-pull RESET output drives low when VCC falls below threshold and remains asserted for the full timeout after VCC recovers. Output logic is valid down to VCC = 1V, and the device features hysteresis of 4×VTH (≈18.5mV) to prevent chatter near threshold crossing.

Key Specifications

Pinout & Package

The MAX6424UK46+T is housed in a 5-pin SOT23-5 package with exposed pad (RoHS-compliant lead-free). Pin 1 is SRT (Set Reset Timeout), Pin 2 is GND, Pin 3 is RESET (active-low push-pull output), Pin 4 is N.C. (not internally connected), and Pin 5 is VCC (supply and threshold monitor input).

Key Features

Applications

Equivalent & Alternatives

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

Compared with NCP302LSN46T1G and TLV809EC26DBVR, the MAX6424UK46+T uniquely delivers capacitor-adjustable timeout within a 5-pin SOT23 while maintaining sub-2µA quiescent current and guaranteed 1V operation-enabling precise, low-power, and robust reset control where timing adaptability and brownout resilience are critical.

Availability

The MAX6424UK46+T is available at Aetrix Electronics and suitable for automotive body control modules, portable medical monitors, and industrial PLC I/O modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6424UK46+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

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Wilmington, MA.

The MAX6424UK46+T belongs to the MAX6340/MAX6421–MAX6426 family of low-power, capacitor-adjustable microprocessor supervisors designed for reliable power-monitoring in battery-powered, automotive, and industrial systems.

FAQ

What is the exact reset threshold voltage of the MAX6424UK46+T?

The MAX6424UK46+T has a factory-trimmed nominal reset threshold of 4.625V, with ±1.5% accuracy at +25°C and ±2.5% over the full –40°C to +125°C operating range. This value is laser-trimmed and specified in Table 1 of the datasheet under suffix "46". The MAX6424UK46+T uses this precise threshold to detect undervoltage on 5V system rails before logic corruption occurs.

Does the MAX6424UK46+T require an external capacitor to function?

No-the MAX6424UK46+T operates without an external capacitor, delivering a minimum reset timeout of 275µs when the SRT pin is left unconnected. Adding a capacitor between SRT and GND extends the timeout linearly: tRP = 2.73×10⁶ × CSRT + 275µs. The MAX6424UK46+T supports timeout adjustment from 0.275ms to over 5ms, enabling design flexibility without firmware changes.

Can the MAX6424UK46+T drive a reset pin directly without a pullup resistor?

Yes-the MAX6424UK46+T features an active-low push-pull RESET output, meaning it actively drives both high and low states. Unlike open-drain supervisors, it does not require an external pullup resistor. The MAX6424UK46+T guarantees VOH ≥ 0.8×VCC and VOL ≤ 0.3V (at ISINK = 1.2mA), ensuring direct, robust interface to standard µP reset inputs.

Is the MAX6424UK46+T qualified for automotive applications?

The MAX6424UK46+T is rated for –40°C to +125°C operation and meets AEC-Q100 stress test requirements per the MAX6340UK31/V+T variant documentation; however, the MAX6424UK46+T itself is not explicitly AEC-Q100 certified in the provided datasheet. For automotive use, confirm qualification status with Analog Devices' latest product change notices. The MAX6424UK46+T's temperature range and transient immunity make it suitable for non-safety-critical automotive subsystems.

How does the MAX6424UK46+T handle short VCC transients?

The MAX6424UK46+T is immune to negative-going VCC transients ≤50µs wide when the overdrive is ≤100mV below the 4.625V threshold-verified in the "Maximum Transient Duration vs. Reset Threshold Overdrive" graph. This prevents false resets during switching noise or load-step events. The MAX6424UK46+T achieves this via internal filtering and hysteresis, ensuring only sustained undervoltage triggers reset assertion.