Infineon Technologies IRF7834PBF

Overview

IRF7834PBF from Infineon Technologies is a 30V, 4.5mΩ (at V_GS = 10V) N-channel HEXFET Power MOSFET in SO-8 package, optimized as a synchronous rectifier FET in high-frequency DC-DC converters. It delivers ultra-low gate impedance (Q_g = 29nC typ.), fully characterized avalanche capability (E_AS = 100mJ), and low R_DS(on) at 4.5V drive for notebook CPU VRMs and isolated telecom power supplies.

For engineers reviewing the IRF7834PBF datasheet, IRF7834PBF pinout, IRF7834PBF application, or IRF7834PBF equivalent, key selection criteria include its 4.5mΩ on-resistance at 10V, 29nC total gate charge, 30V V_DS rating, SO-8 thermal performance (R_θJA = 50°C/W), and body diode reverse recovery charge (Q_rr = 13–20nC) for synchronous rectification efficiency validation.

Technical Context

This device operates as a low-side synchronous rectifier in non-isolated buck and isolated forward/flyback topologies, where fast switching (t_d(off) = 18ns, t_f = 5.0ns) and low output charge (Q_oss = 19nC) minimize turn-off losses and voltage overshoot during hard commutation. Its gate threshold voltage (V_GS(th) = 1.35–2.25V) enables robust 4.5V logic-level drive compatibility with modern PWM controllers.

The SO-8 package supports dual-source layout with drain-connected pins (1–4) and source-connected pins (5–8), enabling parallel conduction paths and reduced PCB trace inductance. Avalanche-rated design (I_AR = 16A, E_AS = 100mJ) ensures reliability under unclamped inductive switching in high-di/dt environments like VRM phase nodes.

Key Specifications

Pinout & Package

IRF7834PBF uses an SO-8 surface-mount package with exposed drain pad for enhanced thermal conduction. Pins 1–4 are internally connected to the drain; pins 5–8 are internally connected to the source; pin 3 is the gate terminal.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous rectifier MOSFET applications.

Compared with Si7852DP-T1-GE3 and IPB040N03L3, IRF7834PBF offers the best balance of low gate charge (29nC), proven SO-8 thermal performance (50°C/W), and avalanche ruggedness (100mJ) for high-frequency, space-constrained synchronous rectifier roles in computing and telecom power.

Availability

IRF7834PBF is available at Aetrix Electronics and suitable for notebook CPU VRMs, server power delivery subsystems, and isolated telecom DC-DC converters requiring stable component supply and long-term lifecycle support.

Supply support for IRF7834PBF 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 German semiconductor manufacturer specializing in power management, automotive, and industrial control ICs and discrete devices.

The IRF7834PBF belongs to the HEXFET® Power MOSFET product line, engineered specifically for high-efficiency synchronous rectification and low-voltage, high-current switching in computing and communications power supplies.

FAQ

What is the maximum continuous drain current at 70°C ambient?

The IRF7834PBF supports 16A continuous drain current at T_A = 70°C with proper PCB copper area (≥1in² 2oz Cu). This rating assumes SO-8 mounting on standard FR-4 with no heatsink and accounts for R_θJA = 50°C/W and junction temperature limit of 150°C. Derating begins linearly above 70°C at 2.5W/°C.

Does IRF7834PBF require a gate resistor for reliable operation?

Yes-a 2–10Ω gate resistor is recommended to dampen ringing caused by PCB trace inductance and MOSFET input capacitance (C_iss = 3710pF). Without it, excessive dv/dt at the drain can couple into the gate via Q_gd, risking unintended turn-on. The resistor also controls dV/dt slew rate to meet EMI limits in Class B power supplies.

How does the body diode's reverse recovery affect synchronous rectifier performance?

The body diode's Q_rr (13–20nC) and t_rr (21–32ns) directly impact shoot-through loss and EMI. During dead-time, stored charge must be removed before the high-side FET turns on; excess Q_rr increases peak current spike and dissipates energy in both FETs. IRF7834PBF's low Q_rr minimizes this loss, especially critical in 500kHz+ VRMs.

Can IRF7834PBF be used in linear regulator applications?

No-it is not designed for linear operation. Its R_DS(on) is optimized for switching, and Safe Operating Area (SOA) curves show limited DC capability beyond 1A at V_DS > 10V. Continuous linear use risks thermal runaway due to positive R_DS(on) temperature coefficient and insufficient SOA margin below 10V.