Infineon Technologies IR3742MTRPBF

Overview

IR3742MTRPBF from Infineon Technologies (formerly International Rectifier) is a 20A integrated PowIRstage® synchronous buck gate driver IC with co-packaged control FET, synchronous FET, Schottky diode, bootstrap diode, and internal 6.8V LDO. It operates from 5–21V input (or 1.0–21V with external VCC bias), supports up to 1.5MHz switching, and delivers 1.2V/20A output for high-performance ASIC/FPGA core power supplies.

For engineers reviewing the IR3742MTRPBF datasheet, IR3742MTRPBF pinout, IR3742MTRPBF application, or IR3742MTRPBF equivalent, key selection criteria include its thermally compensated over-current indicator, open-drain fault signaling, tri-state PWM interface, -40°C to 125°C junction temperature range, and PQFN 5mm × 6mm package with separated PGnd/Gnd terminals.

Technical Context

The IR3742 integrates a custom gate driver with matched high-side (8 mΩ R_DS(on)) and low-side (4 mΩ R_DS(on)) MOSFETs, enabling precise dead-time control (10 ns) and fast propagation delays (19.8 ns low-to-SW, 36.4 ns tri-state-to-high). Its internal LDO regulates VCC/LDO_Out to 6.8V ±0.3V at up to 50mA, with UVLO thresholds of 4.15V (start) and 3.86V (stop).

Over-current detection uses thermal compensation and latches fault on >29–41A current limit; over-temperature shutdown triggers at 145°C. The OC_En pin allows hardware disable of current sensing, while Enable supports resistor-divider-based input UVLO monitoring.

Key Specifications

Pinout & Package

IR3742MTRPBF is housed in a thermally enhanced 5mm × 6mm PQFN package with exposed thermal pad, optimized for PCB heat transfer and low-inductance power routing. Pin 11 (PGnd) is dedicated power ground for MOSFET drivers; Pins 4 and 17 are signal ground (Gnd); Pins 1, 2, 3, 8, 16 are NC and must be tied to signal ground.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar integrated buck stage applications.

Compared with MP86933GQ-Z and ISL95836IRZ-T, IR3742MTRPBF uniquely integrates a Schottky diode and thermally compensated OCP in a 5×6mm PQFN, offering optimal trade-off between integration, thermal safety, and footprint for 20A core rails.

Availability

IR3742MTRPBF is available at Aetrix Electronics and suitable for server CPU core power, FPGA I/O bank supply, AI accelerator memory interface, and enterprise SSD controller rail applications requiring stable component supply and long-term industrial availability.

Supply support for IR3742MTRPBF 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

Infineon Technologies is a global semiconductor leader specializing in power management, automotive, and industrial control solutions, with deep expertise in high-efficiency power conversion.

The PowIRstage® product line delivers fully integrated, thermally optimized power stages for high-current, high-frequency DC/DC conversion in computing and data center applications.

FAQ

What is the recommended PCB layout practice for IR3742MTRPBF's dual ground pins?

Separate PGnd (Pin 11) and Gnd (Pins 4, 17) must connect to distinct copper pours: PGnd ties directly to the power inductor ground plane and MOSFET source pads, while Gnd serves only the control circuitry and feedback network. A single-point star connection between the two grounds near the IC's thermal pad minimizes noise coupling without compromising EMI performance.

Can IR3742MTRPBF operate without an external bootstrap capacitor?

No. A 100nF ceramic capacitor must be placed between Boot and SW pins to sustain high-side gate drive. Omitting it causes immediate loss of high-side FET control and uncontrolled shoot-through. The internal bootstrap diode is not intended for self-biasing; it only supplements charge recycling during light loads.

How does the OC_En pin affect over-current protection behavior?

When OC_En is left floating, over-current detection is active and latches Fault low upon exceeding 29–41A (temp-compensated). When shorted to GND, OC_En disables current sensing entirely - the device continues switching even during overload, relying solely on over-temperature shutdown at 145°C for protection.

What is the minimum PWM pulse width supported, and why does it matter?

The IR3742MTRPBF supports a minimum PWM pulse width of 41–58 ns. This enables fine-grained duty-cycle control down to ~0.3% at 1.5MHz, critical for achieving ultra-low output voltages (e.g., 0.8V) with high accuracy and stability in advanced processor core rails.