STP8NM50FP Equivalent & Substitute Parts

Part Overview

The STP8NM50FP is an N-Channel MOSFET manufactured by STMicroelectronics, rated for 550V drain-to-source voltage with 8A continuous drain current at 25°C. This device is packaged in a TO-220FP through-hole configuration and is part of the MDmesh™ series. The part is currently classified as obsolete, making identification of equivalent and substitute components necessary for ongoing design support, maintenance, and production continuity.

Key Parameters

Parameter	Value	Unit
Manufacturer Part Number	STP8NM50FP	—
Manufacturer	STMicroelectronics	—
FET Type	N-Channel	—
Drain-to-Source Voltage (Vdss)	550	V
Continuous Drain Current (Id) @ 25°C	8	A
On-State Resistance (Rds On) @ 2.5A, 10V	800	mOhm
Gate Threshold Voltage (Vgs(th)) @ 250µA	5	V
Power Dissipation (Max)	25	W
Operating Temperature Range	-65 to 150	°C
Package Type	TO-220-3 Full Pack	—
Mounting Type	Through Hole	—
Product Status	Obsolete	—

Substitute Part Grouping Explanation

Substitution of the STP8NM50FP is determined by the following critical electrical and mechanical parameters:

Primary Substitution Criteria:

FET Type: N-Channel MOSFET technology
Drain-to-Source Voltage (Vdss): Minimum 550V for direct replacement; lower voltage ratings (400V, 500V) are acceptable only when circuit design permits reduced voltage margin
Continuous Drain Current (Id): Minimum 8A at 25°C; higher current ratings provide design margin
On-State Resistance (Rds On): Comparable performance at specified gate voltage (10V)
Gate Threshold Voltage (Vgs(th)): Within ±30V maximum gate voltage specification
Mounting Type: Through-hole configuration required for mechanical compatibility
Package Type: TO-220 family variants acceptable with lead configuration verification

Secondary Compatibility Factors:

Power Dissipation capability
Operating temperature range
RoHS and REACH compliance status
Moisture Sensitivity Level (MSL)

The substitute parts listed below meet these criteria with documented electrical equivalence and mechanical compatibility.

Parameter Comparison

Parameter	STP8NM50FP (Main)	FQPF5N50CYDTU	IRFIB7N50APBF	RJK4006DPP-M0#T2	TK10A55D(STA4,Q,M)	ZDX080N50
Manufacturer	STMicroelectronics	Fairchild Semiconductor	Vishay Siliconix	Renesas Electronics	Toshiba Semiconductor	Rohm Semiconductor
FET Type	N-Channel	N-Channel	N-Channel	N-Channel	N-Channel	N-Channel
Vdss (V)	550	500	500	400	550	500
Id @ 25°C (A)	8	5	6.6	8	10	8
Rds On @ 10V (mOhm)	800	1400	520	800	720	850
Vgs(th) @ 250µA (V)	5	4	4	—	4	4
Gate Charge @ 10V (nC)	13	24	52	20	24	23
Power Dissipation (W)	25	38	60	29	45	40
Operating Temperature (°C)	-65 to 150	-55 to 150	-55 to 150	150	150	150
Package	TO-220-3 Full Pack	TO-220-3 Full Pack, Formed Leads	TO-220-3 Full Pack, Isolated Tab	TO-220-3 Full Pack	TO-220-3 Full Pack	TO-220-3 Full Pack
Product Status	Obsolete	Active	Active	Active	Active	Not For New Designs
RoHS Compliance	ROHS3 Compliant	—	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant

Engineering Selection Recommendations

Direct Replacement (Highest Compatibility):

The TK10A55D(STA4,Q,M) from Toshiba Semiconductor provides the closest electrical match to the STP8NM50FP. Both devices maintain 550V Vdss rating, support 8A+ continuous drain current, and feature comparable on-state resistance characteristics. The TK10A55D offers 10A continuous current, providing additional design margin. This part is actively manufactured and RoHS3 compliant. The TO-220SIS package variant requires verification of lead configuration compatibility with existing PCB layouts designed for TO-220FP.

Alternative Replacement (Acceptable Substitution):

The IRFIB7N50APBF from Vishay Siliconix operates at 500V Vdss with 6.6A continuous drain current. This part is suitable for applications where the 50V voltage margin reduction is acceptable within circuit design parameters. The device features superior on-state resistance (520 mOhm) compared to the main part, resulting in lower power dissipation and improved thermal performance. Active product status and RoHS3 compliance support long-term availability.

The ZDX080N50 from Rohm Semiconductor matches the 8A current rating and 500V voltage specification. On-state resistance (850 mOhm) is comparable to the main part. However, this device is classified as "Not For New Designs," limiting its suitability for new production applications despite current inventory availability.

Limited Substitution (Reduced Voltage Rating):

The RJK4006DPP-M0#T2 from Renesas Electronics operates at 400V Vdss, representing a 150V reduction from the main part specification. This device is suitable only for applications where circuit design permits reduced voltage headroom. The 8A current rating and 800 mOhm on-state resistance provide functional equivalence in lower-voltage applications. Active product status and RoHS3 compliance are confirmed.

Not Recommended for Direct Replacement:

The FQPF5N50CYDTU from Fairchild Semiconductor is rated for only 5A continuous drain current, below the 8A requirement of the main part. While the 500V Vdss rating is acceptable, the reduced current capacity limits its application scope. This part is suitable only for designs where current requirements do not exceed 5A.

Frequently Asked Questions (FAQ)

Q: Can the TK10A55D(STA4,Q,M) be used as a direct replacement for the STP8NM50FP?

A: The TK10A55D provides electrical equivalence with matching 550V Vdss and superior 10A continuous current capability. The primary consideration is mechanical compatibility. The TK10A55D uses a TO-220SIS package variant, while the STP8NM50FP uses TO-220FP. Lead configuration and tab isolation must be verified against the existing PCB layout before implementation.

Q: What is the significance of the voltage rating difference between the STP8NM50FP (550V) and substitute parts rated at 500V?

A: The 50V difference represents a 9% reduction in maximum drain-to-source voltage specification. For applications operating below 500V, this difference is not functionally significant. However, for circuits designed with minimal voltage margin or operating near the 550V limit, the reduced rating may compromise circuit reliability. Circuit analysis is required to determine acceptability.

Q: Why is the ZDX080N50 listed as a substitute if it is classified as "Not For New Designs"?

A: The ZDX080N50 is included because it meets the electrical substitution criteria (8A current, 500V voltage, comparable Rds On) and maintains current inventory availability. However, its "Not For New Designs" status indicates that Rohm Semiconductor does not recommend this part for new product development. It is suitable only for maintenance and repair of existing equipment using the original part.

Q: How does on-state resistance (Rds On) affect substitution decisions?

A: On-state resistance directly impacts power dissipation and thermal performance. The STP8NM50FP specifies 800 mOhm at 2.5A and 10V gate voltage. Substitute parts with lower Rds On values (such as IRFIB7N50APBF at 520 mOhm) reduce power loss and improve efficiency. Higher Rds On values increase power dissipation and may require thermal management review. Rds On values within ±20% of the original specification are generally considered acceptable for direct substitution.

Q: What is the importance of gate threshold voltage (Vgs(th)) in MOSFET substitution?

A: Gate threshold voltage determines the minimum gate-source voltage required to turn the device on. The STP8NM50FP specifies 5V at 250µA, while most substitute parts specify 4V. This 1V difference is not functionally significant for standard gate drive circuits operating at 10V or higher. However, for low-voltage gate drive applications, threshold voltage differences must be verified against driver output specifications.

Q: Are all substitute parts compatible with the same PCB footprint?

A: All listed substitute parts use TO-220 family packages with through-hole mounting. However, specific package variants (TO-220FP, TO-220F-3, TO-220SIS, TO-220FL, TO-220FM) may have different lead configurations, tab isolation, and forming specifications. PCB layout verification is required before substitution, particularly regarding lead spacing, tab mounting hole requirements, and thermal pad design.

Q: What compliance certifications should be verified when selecting a substitute part?

A: All listed substitute parts are RoHS3 compliant, meeting European Union restrictions on hazardous substances. REACH compliance status varies: the STP8NM50FP and ZDX080N50 are REACH Unaffected, while the RJK4006DPP-M0#T2 is REACH Affected. For applications subject to REACH regulations, compliance status must be confirmed with the component supplier. All parts carry EAR99 export classification and are classified under HTSUS code 8541.29.0095 or 8542.39.0001.

Q: How should operating temperature range differences be evaluated?

A: The STP8NM50FP specifies -65°C to 150°C operating range, while most substitute parts specify -55°C to 150°C. The 10°C difference at the lower temperature limit is not significant for most industrial applications operating above -55°C. For applications requiring operation below -55°C, the STP8NM50FP or equivalent parts with extended low-temperature ratings must be selected.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message