Infineon Technologies IR3842MTR1PBF

Overview

IR3842MTR1PBF from Infineon Technologies is a highly integrated 4A synchronous buck regulator with internal high- and low-side MOSFETs, programmable switching frequency (250 kHz to 1.5 MHz), precision 0.7 V ±1% reference voltage, and integrated bootstrap diode. It delivers regulated output voltages from 0.7 V to 0.9×Vin across 1.5 V–16 V input, supporting server point-of-load and telecom power rails.

For engineers reviewing the IR3842MTR1PBF datasheet, IR3842MTR1PBF pinout, IR3842MTR1PBF application, or IR3842MTR1PBF equivalent, key selection criteria include its programmable hiccup overcurrent protection, enhanced pre-bias start-up, thermal shutdown, PGood open-drain status output, and compatibility with distributed DC-DC architectures requiring tight output regulation and fast transient response.

Technical Context

The IR3842MTR1PBF implements a current-mode PWM control architecture with an integrated error amplifier (GBWP: 20–40 MHz, slew rate: 7–20 V/μs) and programmable soft-start via external capacitor on SS/SD. Its high-bandwidth compensation path enables stable loop design for low-ESR ceramic output capacitors in high-dV/dt load scenarios.

It features dual ground separation (GND for signal, PGND for power), boot-to-SW voltage monitoring (±0.3 V tolerance), and independent enable and sequencing inputs (Seq) for precise power-up coordination in multi-rail systems. Thermal shutdown activates at 140°C with 20°C hysteresis.

Key Specifications

Pinout & Package

IR3842MTR1PBF uses a thermally enhanced 5 mm × 6 mm Power QFN package with 0.9 mm height and exposed thermal pad (PGND-connected). Pin count: 15. RoHS-compliant, lead-free, halogen-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP2451DT-LF-Z and TPS544B20RTWR, the IR3842MTR1PBF offers unique analog-programmable flexibility (frequency, soft-start, OCP), robust analog sequencing, and integrated PGood-making it optimal for industrial and telecom designs where digital interfaces add unnecessary overhead.

Availability

IR3842MTR1PBF is available at Aetrix Electronics and suitable for server applications, storage subsystems, and embedded telecom systems requiring stable component supply, long-lifecycle support, and consistent parametric performance across production batches.

Supply support for IR3842MTR1PBF 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 silicon and silicon carbide power devices.

The IR3842 belongs to Infineon's SupIRBuck™ family of integrated POL regulators, designed specifically for high-efficiency, space-constrained DC-DC conversion in datacenter, networking, and communications infrastructure.

FAQ

What is the minimum recommended output capacitance for stable operation?

The IR3842MTR1PBF requires ≥22 μF total ceramic output capacitance with low ESR (≤5 mΩ) for stability across all loads and temperatures. Typical designs use two 10 μF/6.3 V X5R 0805 capacitors placed adjacent to the SW and PGND pins to minimize loop inductance and suppress high-frequency ringing.

Can the IR3842MTR1PBF operate with a 3.3 V input supply?

Yes - the IR3842MTR1PBF supports input voltages as low as 1.5 V, so 3.3 V is well within its operational range. At 3.3 V input, maximum output voltage is 2.97 V (0.9×Vin), and efficiency remains above 92% at 4 A load with appropriate inductor selection (e.g., 1.0 μH).

How is the overcurrent threshold set, and does it scale with frequency?

The OCSet pin current scales linearly with switching frequency: 23.6 μA at 250 kHz, 48.8 μA at 500 kHz, and 154 μA at 1.5 MHz. A resistor from OCSet to SW sets the current limit threshold (e.g., 10 kΩ yields ~2.4 A limit at 500 kHz); full details are in Section 6.3 of the datasheet.

Is the thermal pad electrically connected, and how should it be routed?

Yes - the exposed thermal pad is internally connected to PGND and must be soldered to a dedicated PGND copper pour on the PCB. Use ≥4 thermal vias (0.3 mm diameter) connecting the pad to inner-layer PGND planes to achieve θ_JA ≈ 35°C/W and maintain junction temperature below 125°C at full 4 A load.