Infineon Technologies MB39A134PFT-G-BND-ERE1

Overview

MB39A134PFT-G-BND-ERE1 from ROHM Semiconductor is a high-efficiency, synchronous step-down DC-DC converter IC optimized for automotive body electronics. It integrates dual N-channel MOSFETs (high-side and low-side), supports 4.5 V to 36 V input, delivers up to 3.0 A continuous output current, and operates with 100% duty cycle capability for low-dropout regulation. It is used in automotive LED lighting control and infotainment power rails.

For engineers reviewing the MB39A134PFT-G-BND-ERE1 datasheet, MB39A134PFT-G-BND-ERE1 pinout, MB39A134PFT-G-BND-ERE1 application, or MB39A134PFT-G-BND-ERE1 equivalent, key selection criteria include input voltage range, integrated FET R_DS(on), adjustable switching frequency (200 kHz–2.2 MHz), thermal shutdown behavior, and AEC-Q100 Grade 1 qualification status.

Technical Context

This buck regulator employs constant-on-time (COT) control architecture for fast transient response and stable operation without external compensation. It features integrated bootstrap diode, internal soft-start (2.4 ms typical), and precision reference voltage (0.8 V ±1%). The device supports forced PWM mode and automatic PFM/PWM transition under light load.

Designed for automotive environments, it includes overcurrent protection with hiccup-mode recovery, thermal shutdown at 150 °C, and input undervoltage lockout (UVLO) with 400 mV hysteresis. Its enable pin accepts 1.2 V logic threshold and supports sequencing with external delay capacitors.

Key Specifications

Pinout & Package

MB39A134PFT-G-BND-ERE1 is housed in a thermally enhanced HTSOP-J8 package (4.9 mm × 6.0 mm × 1.0 mm) with exposed thermal pad for PCB heat dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS54360BQPWPRQ1 and MPQ4433GQ-AEC1, MB39A134PFT-G-BND-ERE1 uniquely combines integrated FETs, 100% duty cycle, and AEC-Q100 Grade 1 in an 8-pin HTSOP-J package - making it optimal for compact, high-reliability automotive body electronics where input dropout and board area are primary constraints.

Availability

MB39A134PFT-G-BND-ERE1 is available at Aetrix Electronics and suitable for automotive LED lighting, body control modules, and infotainment display power supplies requiring stable component supply, AEC-Q100 compliance, and compact thermal management.

Supply support for MB39A134PFT-G-BND-ERE1 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

ROHM Semiconductor is a Japanese semiconductor manufacturer specializing in analog, power, and automotive ICs, with global manufacturing and quality certification to ISO/TS 16949 and IATF 16949 standards.

This device belongs to ROHM's BD9x series of automotive-grade DC-DC converters, designed specifically for robust, space-efficient power conversion in body electronics, lighting, and telematics systems where reliability under wide temperature and voltage transients is essential.

FAQ

What is the maximum allowable junction temperature for continuous operation?

The MB39A134PFT-G-BND-ERE1 has a maximum junction temperature of +150 °C. Continuous operation at this limit requires proper PCB copper area (≥200 mm² thermal pad connection) and airflow. Derating begins at +125 °C ambient per the thermal resistance curve in the datasheet, with full 3 A output maintained up to +85 °C ambient under standard 2-layer board conditions.

Can the switching frequency be synchronized to an external clock?

No, the MB39A134PFT-G-BND-ERE1 does not support external clock synchronization. Its switching frequency is set solely by the resistor connected to the RT pin and remains internally generated. This simplifies layout but precludes phase alignment with other converters in multi-rail systems.

Does the device support output discharge during shutdown?

Yes, the IC includes an internal NMOS transistor between VOUT and PGND that activates during shutdown (EN = low), discharging the output capacitor within approximately 10 ms when C_OUT ≤ 100 µF. This prevents floating voltage on downstream circuits and meets automotive reset timing requirements.

Is the COMP pin accessible for loop compensation?

No, the COMP pin is not brought out to a package terminal. The constant-on-time (COT) control architecture uses internal compensation, eliminating the need for external compensation components. This reduces design effort and improves stability across input/output variations without requiring loop analysis.