Analog Devices Inc./Maxim Integrated MAX6425UK26+T

Overview

MAX6425UK26+T from Analog Devices is a low-power microprocessor supervisor IC with open-drain active-low reset output, 2.625V ±2.5% factory-trimmed reset threshold, capacitor-adjustable reset timeout (3.0–5.75ms with 1500pF), and guaranteed operation down to VCC = 1V. It monitors supply voltage in battery-powered embedded controllers and portable equipment.

For engineers reviewing the MAX6425UK26+T datasheet, MAX6425UK26+T pinout, MAX6425UK26+T application, or MAX6425UK26+T equivalent, key selection factors include its SOT23-5 open-drain RESET output, 1.6µA typical quiescent current, -40°C to +125°C operating range, and compatibility with multi-rail logic interfacing via external pullup.

Technical Context

The MAX6425UK26+T implements a precision voltage-detection architecture using laser-trimmed resistors to set its 2.625V reset threshold with ±2.5% accuracy over temperature. Its reset assertion is triggered by VCC falling below this threshold and held for a timeout period determined by an external capacitor on the SRT pin.

A 240nA internal ramp current charges the SRT capacitor to a 0.65V internal reference; reset deassertion occurs when that voltage is reached. The open-drain RESET output supports wired-OR configurations and logic-level translation across supplies up to 5.5V.

Key Specifications

Pinout & Package

MAX6425UK26+T is housed in a 5-pin SOT23-5 package with 0.95mm pitch, 2.9mm × 1.6mm footprint, and exposed pad for thermal performance. Pin 3 is NC (not internally connected) and may be tied to GND for mechanical stability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6425UK26+T, NCP302HS26T1G offers simpler integration but sacrifices timeout flexibility, while TLV803EB26DBZR delivers lower quiescent current at the cost of programmability - both require layout changes due to differing pinouts and output drive types.

Availability

MAX6425UK26+T is available at Aetrix Electronics and suitable for portable medical monitors, battery-powered industrial sensors, and automotive body control modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6425UK26+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, serving industrial, automotive, communications, and healthcare markets.

The MAX6421–MAX6426 family was designed specifically for ultra-low-power, precision voltage supervision in space- and energy-constrained embedded systems where reliability across wide temperature and supply ranges is critical.

FAQ

What is the exact reset threshold voltage of the MAX6425UK26+T?

The MAX6425UK26+T features a factory-laser-trimmed reset threshold of 2.625V, with guaranteed accuracy of ±2.5% over the full -40°C to +125°C operating temperature range. This value is confirmed in the Electrical Characteristics table of the official Analog Devices datasheet (Rev 11, 9/24), where VTH = 2.625V is explicitly listed for suffix "26". The MAX6425UK26+T maintains this precision without external calibration.

Does the MAX6425UK26+T support capacitor-adjustable reset timeout, and how is it configured?

Yes, the MAX6425UK26+T supports capacitor-adjustable reset timeout via the SRT pin. A capacitor (CSRT) is connected between SRT and GND; the timeout period tRP follows tRP = 2.73 × 10⁶ × CSRT + 275µs (with tRP in seconds and CSRT in farads). For example, a 1500pF capacitor yields 3.0–5.75ms timeout. The MAX6425UK26+T uses a 240nA internal ramp current charging CSRT to a 0.65V reference to determine deassertion timing.

What package type and pin count does the MAX6425UK26+T use?

The MAX6425UK26+T is packaged in a 5-pin SOT23-5 (U5+2) outline with 0.95mm lead pitch, 2.9mm × 1.6mm body size, and exposed thermal pad. Pin 1 is SRT, Pin 2 is GND, Pin 3 is N.C., Pin 4 is VCC, and Pin 5 is open-drain RESET. This matches the mechanical dimensions and land pattern specified in Analog Devices' Package Outline No. 21-0057 and Land Pattern No. 90-0174.

Can the MAX6425UK26+T operate reliably at VCC = 1.0V?

Yes, the MAX6425UK26+T guarantees valid RESET output functionality down to VCC = 1.0V, as stated in the Absolute Maximum Ratings and Electrical Characteristics sections. At 1.0V, the open-drain RESET remains functional with VOL ≤ 0.3V at ISINK = 50µA, and the reset comparator continues asserting RESET until VCC rises above 2.625V. This capability is critical for detecting pre-failure brownout conditions before complete power loss.

Is the MAX6425UK26+T pin-compatible with other devices in the MAX642x family?

The MAX6425UK26+T shares the same 5-pin SOT23-5 package and pinout with MAX6340, MAX6424, and MAX6426 variants, making it mechanically and electrically compatible within that group. However, it is not pin-compatible with 4-pin SC70/SOT143 variants like MAX6421/MAX6422/MAX6423. The MAX6425UK26+T's open-drain output differs from MAX6424's push-pull output, so direct substitution requires verifying RESET drive requirements and pullup presence.