Analog Devices Inc./Maxim Integrated MAX25301BATB/V+

Overview

MAX25301BATB/V+ from Maxim Integrated is an AEC-Q100 qualified automotive low-noise linear regulator delivering up to 1A output current with 7µVRMS output noise (10Hz–100kHz), ±1% DC accuracy over load/line/temperature, and only 100mV dropout at full load. It operates from 1.7V to 5.5V input and supports adjustable output voltage from 0.6V to 5.3V via external resistors - ideal for powering sensitive analog circuitry in automotive ADAS sensors and infotainment power rails.

For engineers reviewing the MAX25301BATB/V+ datasheet, MAX25301BATB/V+ pinout, MAX25301BATB/V+ application, or MAX25301BATB/V+ equivalent, key selection considerations include its active-high POK signal for reliable load startup sequencing, programmable soft-start rate via BYP capacitor, reverse-current protection, and thermal shutdown behavior at 165°C junction temperature.

Technical Context

The MAX25301BATB/V+ implements a pMOS-based LDO architecture with internal 0.6V reference and feedback-controlled error amplifier. Its POK output asserts high when VOUT reaches ≥91% of regulation, enabling precise power-good monitoring without external comparators.

It features dual-stage protection: current limiting (1.4A typ) combined with thermal foldback that cycles output on/off between 150°C and 165°C during sustained overload, plus reverse-current blocking triggered when VIN falls 10mV below VOUT - critical for automotive stop-start and battery-backup scenarios.

Key Specifications

Pinout & Package

MAX25301BATB/V+ is housed in a 10-pin TDFN package (3mm × 3mm) with exposed thermal pad (EP), optimized for automotive PCB space constraints and thermal dissipation. The EP must be soldered to a ground plane with ≥4 thermal vias for θJA = 41°C/W on four-layer boards.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO regulator applications.

Compared with TPS7B8750QKVURQ1 and NCP163AMX500TBG, the MAX25301BATB/V+ uniquely combines 1A output, 7µVRMS noise, AEC-Q100 qualification, and active-high POK in a 3mm × 3mm TDFN - making it the only option among the three capable of serving as a primary analog rail in safety-critical automotive subsystems.

Availability

MAX25301BATB/V+ is available at Aetrix Electronics and suitable for automotive ADAS sensor power supplies, infotainment audio rails, telematics module core logic, and body control unit MCU rails requiring stable component supply across extended temperature and long product lifecycles.

Supply support for MAX25301BATB/V+ 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, mixed-signal, and power management ICs for automotive, industrial, and communications markets.

The MAX25301A/B family targets automotive power management with emphasis on low-noise, high-accuracy, and robust protection - specifically engineered for ADAS, infotainment, and telematics subsystems demanding AEC-Q100 compliance and thermal resilience.

FAQ

What is the minimum output capacitance required for stable operation of the MAX25301BATB/V+?

The MAX25301BATB/V+ requires a minimum of 4µF output capacitance (X5R or X7R ceramic) with ESR <0.03Ω to ensure loop stability across temperature and DC bias. This value accounts for capacitance derating; using a 10µF/6.3V X7R capacitor is recommended for margin. The MAX25301BATB/V+ will oscillate or exhibit poor transient response if COUT falls below this threshold.

Does the MAX25301BATB/V+ support adjustable output voltage, and how is it configured?

Yes, the MAX25301BATB/V+ supports adjustable output voltage from 0.6V to 5.3V using an external resistor divider connected to the FB pin. The formula is VOUT = 0.6V × (1 + R1/R2), with R2 ≤ 300kΩ to minimize error from FB input bias current. For example, setting VOUT = 3.3V requires R1 = 1.35MΩ when R2 = 300kΩ. The MAX25301BATB/V+ does not support pin-selectable voltages like the MAX25301A variant.

What is the function and electrical behavior of the POK pin on the MAX25301BATB/V+?

The POK (Power-OK) pin on the MAX25301BATB/V+ is an active-high open-drain output that signals when the regulated output has reached ≥91% of its target voltage. It remains low during startup and faults, and pulls high only when VOUT is in regulation. An external pullup resistor (e.g., 10kΩ to 3.3V or 5V) is required. During overload or shutdown, POK returns low within microseconds - enabling precise reset coordination in automotive microcontroller systems.

How does the MAX25301BATB/V+ implement reverse-current protection, and what triggers it?

The MAX25301BATB/V+ implements reverse-current protection by detecting when VIN falls 10mV below VOUT. Upon detection, it shuts off the internal pMOS pass device and opens the body diode path, blocking reverse current flow. This feature activates automatically during battery disconnect, cold-crank recovery, or input rail collapse - preventing uncontrolled discharge from the output capacitor into the input. The MAX25301BATB/V+ resumes normal operation once VIN rises above VOUT + 10mV.

What thermal design guidance applies to the MAX25301BATB/V+ in automotive PCB layouts?

The MAX25301BATB/V+ uses a 10-pin TDFN package with an exposed thermal pad (EP) that serves as the primary heat conduction path. To achieve θJA = 41°C/W, the EP must be soldered to a solid internal or bottom-layer GND plane with ≥4 thermal vias (0.3mm diameter, spaced evenly). Avoid thermal isolation; connect EP directly to chassis ground if possible. Derate power dissipation above +70°C ambient at 24.4mW/°C - critical for under-hood placement where ambient may reach +105°C.