BUL741FP Equivalent & Substitute Parts

Part Overview

The BUL741FP is an NPN bipolar junction transistor manufactured by STMicroelectronics, rated for 400 V collector-emitter breakdown voltage and 2.5 A maximum collector current. The device is packaged in a TO-220-3 Full Pack configuration for through-hole mounting applications. The BUL741FP is classified as obsolete, necessitating identification of active equivalent parts for new designs and ongoing production requirements. Substitute parts must maintain electrical and mechanical compatibility while offering current availability and active product status.

Substiute Parts

BUL741FP

STMicroelectronicsIn Stock: 742BUL741FP Datasheet

Current PartRFQ

BUL741

STMicroelectronicsIn Stock: 2028BUL741 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the BUL741FP is determined by strict equivalence across the following electrical and mechanical parameters:

Electrical Parameters (Must Match):

• Transistor Type: NPN
• Voltage - Collector Emitter Breakdown (Max): 400 V
• Current - Collector (Ic) (Max): 2.5 A
• Vce Saturation (Max) @ Ib, Ic: 1.5V @ 600mA, 2A
• Current - Collector Cutoff (Max): 250µA
• DC Current Gain (hFE) (Min) @ Ic, Vce: 25 @ 450mA, 3V
• Operating Temperature (TJ): 150°C

Mechanical Parameters (Must Match):

• Mounting Type: Through Hole
• Package / Case: TO-220-3

Compliance Parameters (Must Match):

• RoHS Status: ROHS3 Compliant
• Moisture Sensitivity Level (MSL): 1 (Unlimited)

The BUL741 (non-FP variant) qualifies as a direct substitute based on identical electrical specifications and compatible packaging within the TO-220-3 family. The primary distinction is packaging format (Tube versus Full Pack) and power rating (60 W versus 30 W), with the substitute offering enhanced thermal performance.

Parameter Comparison

Engineering Selection Recommendations

The BUL741 serves as the direct substitute for the obsolete BUL741FP. Selection of the BUL741 is supported by the following engineering criteria:

Product Status: The BUL741 maintains active product status with STMicroelectronics, ensuring continued availability and supply chain reliability. The BUL741FP is classified as obsolete, making the BUL741 the appropriate replacement for new designs and production continuity.

Electrical Equivalence: All critical electrical parameters are identical between the two parts, including collector-emitter breakdown voltage (400 V), maximum collector current (2.5 A), saturation voltage characteristics, and DC current gain specifications. These parameters ensure functional interchangeability in circuit applications.

Compliance Certification: Both parts maintain ROHS3 compliance and identical moisture sensitivity levels (MSL 1 - Unlimited), satisfying regulatory and environmental requirements without modification to assembly or handling procedures.

Packaging Compatibility: Both parts utilize the TO-220-3 through-hole package, enabling direct mechanical substitution on existing printed circuit boards without layout modifications.

Enhanced Thermal Performance: The BUL741 offers a maximum power rating of 60 W compared to the BUL741FP rating of 30 W, providing improved thermal headroom in applications operating near maximum power dissipation limits.

Frequently Asked Questions (FAQ)

Q: Can the BUL741 be used as a direct replacement for the BUL741FP in existing designs?

A: Yes. The BUL741 is electrically and mechanically equivalent to the BUL741FP across all specified parameters. Both parts share identical electrical characteristics, operating temperature limits, and TO-220-3 package configuration. The primary difference is packaging format (Tube versus Full Pack) and power rating, with the BUL741 offering enhanced thermal performance.

Q: What is the difference between BUL741FP and BUL741 packaging?

A: The BUL741FP is supplied in Full Pack format, while the BUL741 is supplied in Tube packaging. Both use the TO-220-3 through-hole package configuration. The packaging difference affects supply and handling but does not impact electrical performance or circuit compatibility.

Q: Why is the BUL741FP classified as obsolete?

A: The BUL741FP has been discontinued by STMicroelectronics. The active equivalent BUL741 provides identical electrical specifications and is the recommended replacement for new designs and production applications.

Q: Are there any thermal considerations when substituting the BUL741 for the BUL741FP?

A: The BUL741 has a higher maximum power rating (60 W versus 30 W), indicating improved thermal performance. This enhancement allows operation in applications with higher power dissipation without exceeding device limits. Existing thermal designs for the BUL741FP remain valid for the BUL741.

Q: Do both parts meet the same compliance standards?

A: Yes. Both the BUL741FP and BUL741 are ROHS3 compliant and carry identical moisture sensitivity levels (MSL 1 - Unlimited). No changes to assembly, storage, or handling procedures are required when substituting between these parts.

Q: What are the key electrical parameters that must match for substitution?

A: Substitution requires matching of collector-emitter breakdown voltage (400 V), maximum collector current (2.5 A), saturation voltage (1.5V @ 600mA, 2A), collector cutoff current (250µA), and DC current gain (25 @ 450mA, 3V). All these parameters are identical between the BUL741FP and BUL741.

Q: Is the BUL741 available in the same through-hole package?

A: Yes. The BUL741 uses the TO-220-3 through-hole package, identical to the BUL741FP. Direct mechanical substitution on printed circuit boards is possible without layout modifications.