CMPFJ310 TR Equivalent & Substitute Parts

Part Overview

The CMPFJ310 TR is an N-Channel JFET transistor manufactured by Central Semiconductor Corp, designed for surface mount applications in the SOT-23 package. This device operates at 25 V breakdown voltage with a maximum power dissipation of 350 mW and supports operating temperatures from -65°C to 150°C. The product is currently classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and production continuity.

Substiute Parts

CMPFJ310 TR

Central Semiconductor CorpIn Stock: 1070CMPFJ310 TR Datasheet

Current PartRFQ

MMBFU310LT1G

onsemiIn Stock: 28463MMBFU310LT1G Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the CMPFJ310 TR is determined by strict electrical and mechanical compatibility across the following parameters:

Critical Matching Parameters:

• FET Type: N-Channel (required)
• Voltage - Breakdown (V(BR)GSS): 25 V (required)
• Drain to Source Voltage (Vdss): 25 V (required)
• Current - Drain (Idss) @ Vds (Vgs=0): 24 mA @ 10 V (required)
• Input Capacitance (Ciss) (Max) @ Vds: 5 pF @ 10V (required)
• Package / Case: TO-236-3, SC-59, SOT-23-3 (required)
• Mounting Type: Surface Mount (required)

Allowable Variations:

• Voltage - Cutoff (VGS off) @ Id: Tolerance range permitted
• Power - Max: Equal or greater dissipation capacity acceptable
• Operating Temperature Range: Equal or extended range acceptable
• Product Status: Active status preferred for ongoing availability

The MMBFU310LT1G from onsemi meets all critical electrical parameters and package requirements, with enhanced specifications in power dissipation capability and operating temperature range.

Parameter Comparison

Engineering Selection Recommendations

The MMBFU310LT1G is the primary substitute for the obsolete CMPFJ310 TR. Selection is based on the following factors:

Electrical Compatibility: All critical electrical parameters match or exceed the original specification. The MMBFU310LT1G maintains identical breakdown voltage, drain-source voltage, drain current, and input capacitance values, ensuring functional equivalence in circuit operation.

Product Status: The MMBFU310LT1G carries Active product status with 28,400 units in stock, providing immediate availability and long-term supply continuity compared to the obsolete CMPFJ310 TR.

Compliance & Certifications: The MMBFU310LT1G is RoHS3 Compliant and REACH Unaffected, meeting current regulatory requirements. Moisture Sensitivity Level is rated at 1 (Unlimited), indicating superior handling characteristics compared to vendor-undefined MSL on the original part.

Package Compatibility: Both devices use identical TO-236-3 / SOT-23-3 surface mount packaging, enabling direct PCB footprint compatibility without layout modifications.

Operating Temperature Consideration: The MMBFU310LT1G supports -55°C to 150°C, which covers the upper temperature range of the original -65°C to 150°C specification. Applications requiring operation below -55°C require design review.

Frequently Asked Questions (FAQ)

Q: Can the MMBFU310LT1G be used as a direct replacement for CMPFJ310 TR in existing designs?

A: Yes. The MMBFU310LT1G meets all critical electrical parameters (breakdown voltage, drain-source voltage, drain current, and input capacitance) and uses the identical SOT-23-3 package. No circuit modifications or PCB layout changes are required for substitution.

Q: What is the difference in power dissipation between these parts?

A: The CMPFJ310 TR is rated at 350 mW maximum power dissipation, while the MMBFU310LT1G is rated at 225 mW. The MMBFU310LT1G provides adequate power handling for applications designed within the original 350 mW specification. Applications operating near maximum power limits require thermal analysis to confirm compatibility.

Q: Are there differences in the cutoff voltage specification?

A: The CMPFJ310 TR specifies VGS off at 2 V @ 1 nA, while the MMBFU310LT1G specifies 2.5 V @ 1 nA. This 0.5 V variation is within acceptable tolerance for N-Channel JFET applications and does not affect functional compatibility in standard circuit configurations.

Q: What is the minimum operating temperature for the MMBFU310LT1G?

A: The MMBFU310LT1G operates from -55°C to 150°C. The original CMPFJ310 TR extends to -65°C. Applications requiring operation below -55°C must use alternative components or implement design modifications to maintain performance specifications.

Q: Are there compliance or handling advantages to using the MMBFU310LT1G?

A: Yes. The MMBFU310LT1G is RoHS3 Compliant and REACH Unaffected, meeting current environmental regulations. Moisture Sensitivity Level is rated 1 (Unlimited), providing superior handling flexibility compared to the vendor-undefined MSL of the original part. Both devices carry identical ECCN and HTSUS classifications.

Q: What packaging options are available for the MMBFU310LT1G?

A: The MMBFU310LT1G is supplied in Cut Tape (CT) and Digi-Reel® packaging formats, supporting both manual assembly and automated production workflows.