IRFZ46Z N-Channel 55V 51A MOSFET Equivalent & Substitute Parts

Part Overview

The IRFZ46Z is an N-Channel MOSFET manufactured by Infineon Technologies, rated for 55V drain-to-source voltage and 51A continuous drain current in a TO-220AB through-hole package. This device is classified as obsolete, making equivalent and substitute parts necessary for new designs and production continuity. The IRFZ46Z operates across a temperature range of -55°C to 175°C and dissipates up to 82W at the case temperature. Substitute parts must maintain electrical compatibility across voltage ratings, current handling, gate drive characteristics, and thermal performance while accommodating packaging variations.

Substiute Parts

IRFZ46Z

Infineon TechnologiesIn Stock: 2325IRFZ46Z Datasheet

Current PartRFQ

HUF75332P3

onsemiIn Stock: 9356HUF75332P3 Datasheet

MFR RecommendedRFQ

HUF75339P3

onsemiIn Stock: 28331HUF75339P3 Datasheet

MFR RecommendedRFQ

HUF75344P3

onsemiIn Stock: 21987HUF75344P3 Datasheet

MFR RecommendedRFQ

PHP191NQ06LT,127

Nexperia USA Inc.In Stock: 3002PHP191NQ06LT,127 Datasheet

MFR RecommendedRFQ

STP60NF06L

STMicroelectronicsIn Stock: 2750STP60NF06L Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the IRFZ46Z is determined by the following critical parameters:

Voltage Rating Compatibility: All substitute parts must maintain a Vdss rating of 55V or higher to ensure safe operation within the original design envelope.

Current Handling: Substitute parts must support a continuous drain current (Id) equal to or greater than 51A at 25°C to meet or exceed the original performance specification.

Gate Drive Voltage: The drive voltage for maximum Rds On must be compatible with 10V operation, ensuring proper gate control in existing circuits.

Gate Threshold Voltage: Vgs(th) must remain within acceptable limits (4V nominal) to maintain consistent switching behavior.

Thermal Performance: Power dissipation capability must support the thermal requirements of the application. Higher power ratings provide design margin.

Package Compatibility: TO-220AB and TO-220-3 packages are mechanically and electrically compatible for through-hole mounting applications.

Compliance Status: Active product status and RoHS3 compliance are preferred for new designs; obsolete parts are acceptable for legacy system support.

Parameter Comparison

Engineering Selection Recommendations

HUF75332P3 (onsemi UltraFET™): This substitute provides 60A continuous drain current with 55V Vdss rating, exceeding the IRFZ46Z current specification by 18%. The 19mOhm Rds On at 60A, 10V is slightly higher than the original part's 13.6mOhm specification. Power dissipation capability of 145W provides 77% additional thermal margin. Active product status and ROHS3 compliance make this suitable for new designs. TO-220-3 package is mechanically compatible with TO-220AB footprints.

HUF75339P3 (onsemi UltraFET™): This part delivers 75A continuous drain current at 55V, providing 47% current margin over the IRFZ46Z. The 12mOhm Rds On at 75A, 10V represents improved on-state performance. Power dissipation of 200W offers 144% additional thermal capacity. Active status and ROHS3 compliance support modern production requirements. Higher gate charge (130nC) requires consideration in high-frequency switching applications.

HUF75344P3 (onsemi UltraFET™): This device offers 75A at 55V with the lowest on-state resistance of 8mOhm at 75A, 10V, delivering superior efficiency. Power dissipation reaches 285W, providing 248% thermal margin. Active product status and ROHS3 compliance ensure long-term availability. Significantly higher gate charge (210nC) and input capacitance (3200pF) may require gate driver circuit adjustments in high-frequency applications.

PHP191NQ06LT,127 (Nexperia TrenchMOS™): This substitute maintains 55V Vdss and 75A current rating with exceptional on-state resistance of 3.7mOhm at 25A, 10V, enabling lowest conduction losses. Power dissipation of 300W provides maximum thermal headroom. Obsolete product status limits suitability for new designs but remains viable for legacy system support. ROHS3 compliance is confirmed. Lower gate threshold voltage (2V) and reduced Vgs(max) (±15V) require circuit compatibility verification.

STP60NF06L (STMicroelectronics STripFET™ II): This part provides 60A at 60V Vdss, slightly exceeding the original voltage rating. The 14mOhm Rds On at 30A, 10V is comparable to the IRFZ46Z specification. Power dissipation of 110W provides 34% additional thermal capacity. Active product status and ROHS3 compliance support production continuity. Lower gate threshold voltage (1V) and reduced Vgs(max) (±15V) require gate drive circuit compatibility assessment.

Frequently Asked Questions (FAQ)

Q: Can I use a substitute part with higher Vdss rating than the IRFZ46Z?

A: Yes. A higher Vdss rating (such as 60V in the STP60NF06L) is electrically compatible and provides additional voltage margin. The circuit will operate safely within the original 55V design envelope.

Q: What is the significance of on-state resistance (Rds On) differences between substitute parts?

A: Rds On directly affects conduction losses and heat generation. Lower Rds On values (such as 3.7mOhm in the PHP191NQ06LT,127) reduce power dissipation and improve efficiency. Higher values (such as 19mOhm in the HUF75332P3) increase heat generation but remain acceptable if thermal design accommodates the additional power.

Q: Are TO-220AB and TO-220-3 packages interchangeable?

A: Yes. Both packages are mechanically and electrically compatible for through-hole mounting applications. Pin configurations and lead spacing are identical, allowing direct PCB footprint compatibility.

Q: Why do some substitute parts have significantly higher gate charge values?

A: Gate charge (Qg) represents the total charge required to switch the transistor. Higher values (such as 210nC in HUF75344P3) require more gate drive current and longer switching times. Gate driver circuits must supply sufficient current to meet switching frequency requirements. Lower gate charge values enable faster switching with reduced driver power consumption.

Q: What does "Active" product status mean compared to "Obsolete"?

A: Active products are in current production with guaranteed long-term availability and supply continuity. Obsolete products are no longer manufactured and have limited stock availability. For new designs, active products (HUF75332P3, HUF75339P3, HUF75344P3, STP60NF06L) are preferred. Obsolete parts (IRFZ46Z, PHP191NQ06LT,127) are suitable only for legacy system support or replacement applications.

Q: How does RoHS3 compliance affect part selection?

A: RoHS3 compliance indicates the part meets environmental and hazardous substance restrictions required in many markets. The IRFZ46Z is RoHS non-compliant, while all substitute parts listed are ROHS3 compliant. For new designs and regulated applications, ROHS3-compliant substitutes are mandatory.

Q: Can I use a substitute part with lower continuous drain current than 51A?

A: No. The substitute part must support at least 51A continuous drain current to meet the original design specification. Using a lower-rated part risks thermal runaway and device failure under full-load conditions.

Q: What is the impact of different gate threshold voltages on circuit operation?

A: Gate threshold voltage (Vgs(th)) determines the minimum gate voltage required to turn the transistor on. The IRFZ46Z specifies 4V at 250µA. Substitute parts with lower thresholds (such as 1V or 2V) turn on at lower gate voltages, potentially affecting switching timing and circuit behavior. Gate driver circuits must be verified for compatibility with the substitute part's threshold specification.