MPF4393 Equivalent & Substitute Parts

Part Overview

The MPF4393 is an N-Channel JFET transistor rated for 30 V operation in a Through Hole TO-92 package. Designed for general-purpose switching and amplification applications, this component delivers 350 mW maximum power dissipation with a drain current (Idss) of 5 mA at 15 V. The MPF4393 is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and production continuity.

Substiute Parts

MPF4393

onsemiIn Stock: 22444MPF4393 Datasheet

Current PartRFQ

BF256B

onsemiIn Stock: 39931BF256B Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the MPF4393 is determined by strict alignment of electrical and mechanical parameters. The primary substitute identified is the BF256B, which maintains compatibility through the following criteria:

Critical Matching Parameters:

• N-Channel JFET configuration
• 30 V rated voltage (Vdss and V(BR)GSS)
• Through Hole TO-92-3 package compatibility
• Operating temperature range support (-65°C to 150°C)
• Drain current rating within application tolerance (13 mA for BF256B vs. 5 mA for MPF4393)

The BF256B is classified as Active product status, ensuring continued availability and manufacturing support, unlike the obsolete MPF4393.

Parameter Comparison

Engineering Selection Recommendations

The BF256B serves as the direct equivalent for MPF4393 replacement based on the following factors:

Product Status: The BF256B is Active, providing assured long-term availability and manufacturing continuity, whereas the MPF4393 is Obsolete and subject to supply discontinuation.

Regulatory Compliance: The BF256B meets ROHS3 compliance requirements, supporting modern manufacturing and environmental standards. The MPF4393 is RoHS non-compliant, presenting potential regulatory constraints in new designs.

Electrical Compatibility: Both devices share identical voltage ratings (30 V Vdss and V(BR)GSS), N-Channel JFET configuration, and compatible operating temperature ranges. The BF256B's higher current rating (13 mA vs. 5 mA) provides design margin without compromising circuit function.

Package Compatibility: Both components utilize Through Hole TO-92-3 packaging, enabling direct mechanical and electrical substitution without PCB redesign.

Frequently Asked Questions (FAQ)

Q: Can the BF256B directly replace the MPF4393 without circuit modification?

A: Yes. Both devices share identical voltage ratings (30 V), N-Channel JFET configuration, and TO-92-3 Through Hole packaging. The BF256B's higher current rating (13 mA) provides additional design margin. No circuit modification is required for electrical or mechanical compatibility.

Q: What is the primary reason for substituting the MPF4393?

A: The MPF4393 is classified as Obsolete, creating supply risk and potential manufacturing discontinuation. The BF256B is Active status, ensuring continued availability and production support.

Q: Are there compliance differences between the MPF4393 and BF256B?

A: Yes. The BF256B is ROHS3 compliant, while the MPF4393 is RoHS non-compliant. For applications subject to environmental or regulatory requirements, the BF256B is the preferred choice.

Q: Do the devices have identical pin configurations?

A: Both the MPF4393 and BF256B use the TO-92-3 (TO-226) Through Hole package with three leads. Pin-to-pin compatibility is maintained for direct substitution.

Q: What is the impact of the BF256B's higher current rating on circuit performance?

A: The BF256B's 13 mA current rating exceeds the MPF4393's 5 mA specification. This provides additional design margin and does not negatively impact circuit function. Applications designed for the MPF4393 will operate within the BF256B's electrical envelope.