Analog Devices Inc./Maxim Integrated MAX20031BATMB/V+T

Overview

MAX20031BATMB/V+T from Maxim Integrated is an automotive-grade dual synchronous step-down controller with integrated preboost circuit and high-voltage 200mA LDO, designed for front-end power management in cold-crank and stop-start automotive systems. It delivers regulated 5V and 3.3V outputs (±1% FB accuracy), operates from 2V–42V input (with preboost), supports 2.2MHz switching, and achieves 17µA quiescent current with 3.3V buck enabled - enabling always-on instrument cluster and head unit power supplies.

For engineers reviewing the MAX20031BATMB/V+T datasheet, MAX20031BATMB/V+T pinout, MAX20031BATMB/V+T application, or MAX20031BATMB/V+T equivalent, key selection considerations include cold-crank operation down to 2V VIN, resistor-programmable 220kHz–2.2MHz frequency, spread-spectrum EMI reduction, 180° out-of-phase dual-buck operation, and thermally enhanced 48-pin TQFN package with exposed pad.

Technical Context

The MAX20031BATMB/V+T implements three independent current-mode controllers: two synchronous buck channels operating 180° out of phase at up to 2.2MHz, and a dedicated synchronous boost (preboost) channel activated below ~6V input to sustain VOUT1/VOUT2 regulation. Each buck channel features 50ns minimum on-time, 97% max duty cycle, and cycle-by-cycle current limiting.

It integrates a high-voltage 200mA LDO (VINLDO = 3.5V–36V) with 5V/3.3V factory-selectable output, ±1% load/line regulation, and 250mV dropout at 200mA. The device includes PGOOD monitoring per buck output, thermal shutdown at +170°C, and robust protection including overvoltage lockout (109% nominal), undervoltage lockout, and short-circuit detection.

Key Specifications

Pinout & Package

Package: 48-pin thermally enhanced TQFN (7mm × 7mm, exposed pad), RoHS-compliant, outline 21-0144.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-buck + preboost power management applications.

Compared with MAX20030BATMB/V+T, the MAX20031BATMB/V+T adds factory-trimmed EN3 active-low threshold for hardware-triggered preboost activation during battery dip, while MPQ4332GQ-AEC1-P offers lower cost and footprint but demands external circuitry to meet cold-crank requirements.

Availability

MAX20031BATMB/V+T is available at Aetrix Electronics and suitable for instrument cluster, navigation head unit, and distributed DC power systems requiring stable component supply across automotive production lifecycles.

Supply support for MAX20031BATMB/V+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

Maxim Integrated (now part of Analog Devices) is a leader in high-performance analog, mixed-signal, and power management semiconductors for automotive, industrial, and communications markets.

The MAX20031 is part of Maxim's automotive front-end power management portfolio, engineered specifically for ASIL-B compliant systems requiring cold-crank resilience, ultra-low IQ, and EMI-robust operation in space-constrained ECUs.

FAQ

What is the minimum input voltage supported by MAX20031BATMB/V+T during cold-crank conditions?

The MAX20031BATMB/V+T supports operation down to 2V input when the integrated preboost controller is enabled. This capability ensures continuous regulation of both 5V and 3.3V buck outputs during severe automotive cold-crank events, where battery voltage can dip below 3V for up to 1 second. The preboost activates automatically when IN falls below ~6V, maintaining sufficient headroom for the buck stages.

Does MAX20031BATMB/V+T support synchronization to an external clock source?

Yes, MAX20031BATMB/V+T supports external clock synchronization via the FSYNC pin. It accepts external clock frequencies from 250kHz to 2.6MHz (depending on RFOSC setting), with 1:1 ratio locking. This feature enables deterministic timing across multiple power rails and reduces beat-frequency EMI in multi-PMIC systems - critical for radar and camera modules sharing the same PCB.

How is the output voltage of the integrated LDO configured on MAX20031BATMB/V+T?

The LDO output voltage on MAX20031BATMB/V+T is factory-configured as either 5V or 3.3V - the "B" suffix in MAX20031BATMB/V+T indicates the 3.3V LDO option. No external resistor divider is needed for this default output. For adjustable outputs (1.5V–10V), FB4 is connected to a resistor divider between OUT4 and PGND4, referencing the internal 1.25V feedback voltage.

What thermal performance can be expected from MAX20031BATMB/V+T in a 4-layer board layout?

On a standard 4-layer JEDEC-compliant board, MAX20031BATMB/V+T exhibits θJA = 23.3°C/W and θJC = 1°C/W. With proper copper pour on the exposed pad (EP = GND) and thermal vias to inner ground planes, the device sustains full load at +125°C ambient. Derating begins above +70°C at 37mW/°C, supporting >2.5W continuous dissipation in typical automotive under-dash environments.

Can MAX20031BATMB/V+T operate in skip mode, and how is it enabled?

Yes, MAX20031BATMB/V+T supports ultralow-IQ skip mode for light-load efficiency. Skip mode is enabled by grounding the FSYNC pin (FPWM = GND). In this mode, the controller pulses only as needed to maintain regulation, reducing IQ to 17µA (3.3V buck on) or 25µA (5V buck on). Forced PWM mode is selected by connecting FSYNC to BIAS, ensuring constant frequency for EMI-sensitive applications.