IRF9Z34NPBF - 55V P-Ch HEXFET MOSFET, 19A, TO-220 | Infineon
MPN: IRF9Z34NPBF ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.42 | $1.42 |
| 10 | $1.18 | $11.80 |
| 100 | $0.92 | $92.00 |
| 500 | $0.78 | $390.00 |
| 1,000 | $0.65 | $650.00 |
IRF9Z34NPBF Overview
An N-channel MOSFET is a type of field-effect transistor in which the conductive channel is formed by electrons when a positive gate-to-source voltage is applied. In contrast, a P-channel MOSFET (PMOS) uses holes as the charge carriers and turns ON when the gate is pulled below the source. PMOS belongs to the broader MOSFET family -> field-effect transistor -> discrete semiconductor -> power semiconductor, and it is widely used as a high-side switch in power distribution, load switching, battery protection, and DC-DC conversion where the source is tied to the positive rail.
Key features include 55 V Vds, 19 A Id, 68 W power dissipation, 100 milliohm typical Rds(on) at Vgs = -10 V, avalanche-rated dv/dt robustness, and a TO-220AB through-hole package with industry-standard pinout (Gate-Drain-Source). The "PBF" suffix denotes lead-free, halogen-free compliance suitable for RoHS/REACH product designs. The TO-220AB mechanical package is universally preferred for commercial-industrial power dissipation and provides a tab that can be screwed to a heatsink for higher continuous current.
Typical applications include DC motor drives, solenoid drivers, high-side load switches, battery polarity protection, and power OR-ing circuits. In automotive and industrial 12 V/24 V bus systems, this device supports reverse-battery protection and active load management. In a switching topology, it can replace a PNP bipolar transistor or an N-Channel device that would otherwise require a charge pump, simplifying gate drive and reducing component count.
When designing with this part, ensure adequate heatsinking at high continuous currents because TO-220AB thermal resistance is typically ~62 C/W without a heatsink. Use a low-impedance gate driver and add a gate-source resistor (typically 10 kOhm) to prevent unintended turn-on from Miller-induced dv/dt transients. This page synthesizes distributor pricing, drop-in equivalents, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for IRF9Z34NPBF — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with IRF9Z34NPBF (same form factor and footprint) — differing in Technology, Package, Operating Temperature Range, Total Gate Charge (Qg), FET Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
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View Datasheet →IRF9Z34NPBF Maximum Ratings & Electrical Characteristics
| Manufacturer | Infineon Technologies (formerly International Rectifier) |
| Polarity / Channel Type | P-Channel |
| Drain-Source Voltage (Vds) | -55 V |
| Continuous Drain Current (Id) at Tc=25C | -19 A |
| Pulsed Drain Current (Idm) | -72 A |
| Power Dissipation (Pd) at Tc=25C | 68 W |
| On-Resistance Rds(on) at Vgs=-10V | 100 milliohm (typical) |
| Gate Charge (Qg) | 23.3 nC (per Mouser listing) |
| Operating Temperature Range | -55C to +175C (junction) |
| Package | TO-220AB (through-hole, 3-pin) |
| Mounting Type | Through Hole |
| Pinout (G-D-S) | Pin 1 Gate, Pin 2 Drain (tab), Pin 3 Source |
| Technology | HEXFET (5th generation) |
| Lead-Free / Halogen-Free | Yes (PBF suffix) |
| RoHS Status | Compliant |
IRF9Z34NPBF Pin Configuration
| Pin 1 | Gate — MOSFET gate drive input |
| Pin 2 | Drain — Drain terminal (also electrically connected to the metal tab) |
| Pin 3 | Source — MOSFET source terminal |
Safe Operating Area (TO-220AB, Tc=25C)
Typical Applications
IRF9Z34NPBF is suitable for 6 applications: 12V Automotive High-Side Load Switch, DC Motor / Solenoid Driver (H-Bridge High-Side), Battery Reverse-Polarity Protection, Power OR-ing / Redundant Supply Switching, Audio Amplifier Output Stage Protection, Solar Charge Controller / Battery Disconnect.
12V Automotive High-Side Load Switch
The IRF9Z34NPBF's P-Channel polarity lets it act as a high-side load switch on a 12 V automotive bus without a charge pump. With Vds=-55 V it easily handles 14 V system transients plus inductive kick from relays; its 100 milliohm Rds(on) at -19 A keeps conduction loss near 3.6 W at full load. Place the source at the +12 V rail, drive the gate from a low-side NPN driver to GND for turn-on, and add a 10 kOhm pull-up to keep the FET off during MCU reset. Unlike a comparable N-Channel high-side switch it removes the need for a bootstrap capacitor and isolated gate-drive supply.
Recommended
DC Motor / Solenoid Driver (H-Bridge High-Side)
In an H-bridge motor driver the IRF9Z34NPBF serves as the high-side P-Channel switch on each half-bridge leg, sourcing current to the motor when turned on. Its -19 A rating covers fractional-horsepower brushed DC motors and 24 V solenoid coils typical of industrial actuators; the 68 W power dissipation envelope matches continuous armature currents without external cooling in most cases. Drive its gate with a complementary low-side N-Channel pair and dead-time control; the P-Channel source-follower topology simplifies gate timing compared to a bootstrap-driven N-Channel bridge.
Recommended
Battery Reverse-Polarity Protection
The IRF9Z34NPBF is a textbook P-Channel reverse-battery protection FET: place it between the battery + terminal and the downstream load with source toward the battery. Its body diode is oriented to block reverse current, and its 100 milliohm Rds(on) creates only ~1 V drop at 10 A continuous. The -55 V Vds withstands jump-start transients and inductive kickback from motors, while the TO-220AB tab bolts to chassis for heat removal during sustained fault events.
Recommended
Power OR-ing / Redundant Supply Switching
In redundant power OR-ing for telecom and server rails, the IRF9Z34NPBF blocks back-feeding between supplies thanks to its P-Channel orientation and low Rds(on). A small gate amplifier keeps the FET off when the upstream rail is healthy, then turns it on seamlessly when that rail drops. The 55 V rating covers 48 V telecom battery plants with margin, while the 19 A continuous supports a typical 200-300 W load per supply rail in mid-size server backplanes.
Recommended
Audio Amplifier Output Stage Protection
The IRF9Z34NPBF can serve as a DC-offset protection switch between an audio amplifier output and the speaker. Its low Rds(on) keeps series attenuation negligible in the audio band, and its fast switching speeds (~50 ns turn-off typical for HEXFET) interrupt DC faults before the speaker voice coil is damaged. Drive the gate from a fault-detect comparator; the P-Channel topology keeps the speaker referenced to amplifier ground when the switch is closed for minimum THD contribution.
Recommended
Solar Charge Controller / Battery Disconnect
In small off-grid solar systems the IRF9Z34NPBF acts as the P-Channel disconnect switch between the PV panel and the battery bus. Its 55 V rating accommodates 24 V nominal panel open-circuit voltages, while its 19 A continuous current handles 200-300 W solar arrays. The P-Channel source-follower topology lets an MCU GPIO drive the gate directly through a pull-up, simplifying firmware-controlled load shedding at night and overcharge disconnect.
Recommended
Recommended Products Summary
Engineering reference data for IRF9Z34NPBF — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | IRF4905PBF | IRFR5505TRPBF | IRFR5505TRLPBF | IRF7205PBF | IRF7205TRPBF |
|---|---|---|---|---|---|---|
| Brand | Infineon | Infineon | Infineon | Infineon | Infineon | Infineon |
| Package | TO-220AB | TO-220AB - same | TO-220AB - same | TO-220AB - same | TO-220AB - same | TO-220AB - same |
| Polarity | P-Channel | P-Channel | P-Channel | P-Channel | P-Channel | P-Channel |
| Drain-Source Voltage (Vds) | -55 V | -55 V | -55 V | -55 V | -55 V | -55 V |
| Continuous Drain Current (Id) | -19 A | -74 A | -55 A | -55 A | -6.5 A | -6.5 A |
| Lead-Free / Halogen-Free (PBF) | Yes | Yes | Yes | Yes | Yes | Yes |
Key Differentiators
- Lower Rds(on) than IRF7205PBF at the same package and price tier (vs IRF7205PBF)
- Higher Vds headroom than IRFR9024NTRPBF (vs IRFR9024NTRPBF)
- P-Channel high-side topology eliminates charge pump (vs N-Channel high-side (e.g. IPD090N03LGATMA1))
Design Notes
Estimated: At full -19 A continuous drain current and Vgs=-10V drive, conduction loss is approximately 19A x 19A x 0.1 ohm = 36 W (using the typical 100 milliohm Rds(on)). The TO-220AB junction-to-ambient thermal resistance is ~62 C/W without heatsink; with proper heatsinking this rises to a safe 175 C junction. At >10 A continuous load, attach the tab to at least 50 cm^2 of 2 oz copper or a clip-on TO-220 heatsink; without it the device will thermal-limit and may fail. Always derate to 50 percent of Id for reliable long-term operation.
The P-Channel IRF9Z34NPBF requires the gate to be pulled at least 10 V BELOW the source to fully enhance. In high-side switching with the source on a 12 V rail, the gate must swing from +12 V (off) to near 0 V (on). Add a 10 kOhm gate-to-source pull-up resistor to ensure the FET stays off during MCU reset or floating-gate conditions, and place a small (100 Ohm) gate resistor in series to dampen ringing when driving long gate traces.
Keep the gate-drive loop area as small as possible: source return and gate drive traces should be routed in parallel and adjacent to minimise parasitic inductance. The drain tab is the thermal path - if through-hole mounting, ensure the PCB pad pattern provides at least 1 oz copper pour under and around the tab for heat spreading, and that the heatsink thermal compound is correctly applied. Avoid routing sensitive analog signal traces under the drain tab to prevent coupling.
Compliance Information
PBF suffix denotes lead-free, halogen-free per Infineon datasheet. Not AEC-Q100 qualified - not a direct-fit automotive-qualified part; verify with Infineon for automotive designs requiring AEC-Q100.
