CMPTH81 TR Equivalent & Substitute Parts

Part Overview

The CMPTH81 TR is an RF transistor manufactured by Central Semiconductor Corp, classified as a PNP bipolar junction transistor (BJT) designed for radio frequency applications. This component operates at 600MHz transition frequency with a maximum collector-emitter breakdown voltage of 20V and maximum power dissipation of 225mW in a surface mount SOT-23 package.

The CMPTH81 TR is currently listed as obsolete. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production or repair requirements for systems utilizing this component.

Substiute Parts

CMPTH81 TR

Central Semiconductor CorpIn Stock: 1119CMPTH81 TR Datasheet

Current PartRFQ

MMBTH81

onsemiIn Stock: 15492MMBTH81 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the CMPTH81 TR is determined by strict equivalence across the following critical parameters:

Electrical Parameters (Must Match):

• Transistor polarity: PNP
• Voltage - Collector Emitter Breakdown (Max): 20V
• Frequency - Transition: 600MHz
• Power - Max: 225mW
• DC Current Gain (hFE) (Min) @ Ic, Vce: 60 @ 5mA, 10V
• Current - Collector (Ic) (Max): 50mA
• Operating Temperature Range: -55°C ~ 150°C (TJ)

Mechanical Parameters (Must Match):

• Mounting Type: Surface Mount
• Package / Case: TO-236-3, SC-59, SOT-23-3
• Moisture Sensitivity Level (MSL): 1 (Unlimited)

The MMBTH81 from onsemi meets all specified electrical and mechanical parameters and is classified as a direct substitute.

Parameter Comparison

Engineering Selection Recommendations

The MMBTH81 from onsemi is a direct electrical and mechanical equivalent to the obsolete CMPTH81 TR. All critical parameters match exactly, including voltage ratings, frequency response, power dissipation, current gain, and operating temperature range. Both components utilize identical SOT-23-3 surface mount packaging.

The MMBTH81 offers the additional advantage of active product status, ensuring continued availability and supply chain support. The MMBTH81 is ROHS3 compliant, meeting current environmental and regulatory standards. Both components share identical moisture sensitivity classification (MSL 1, Unlimited), eliminating handling and storage requirement changes.

For applications currently using the CMPTH81 TR, direct substitution with the MMBTH81 is supported without circuit modification or re-qualification.

Frequently Asked Questions (FAQ)

Q: Can the MMBTH81 be used as a direct replacement for the CMPTH81 TR?

A: Yes. The MMBTH81 matches all electrical parameters (voltage, frequency, power, current gain, operating temperature) and mechanical parameters (SOT-23-3 package, surface mount, MSL rating) of the CMPTH81 TR. No circuit changes are required.

Q: What is the primary reason for substitution?

A: The CMPTH81 TR is obsolete. The MMBTH81 is an active product with equivalent specifications and improved supply availability.

Q: Are the packages physically identical?

A: Yes. Both components use the TO-236-3 / SC-59 / SOT-23-3 surface mount package. PCB footprints and land patterns are identical.

Q: Do moisture sensitivity requirements differ?

A: No. Both components are classified as MSL 1 (Unlimited), requiring no special moisture control during storage or handling.

Q: Is the MMBTH81 compliant with current environmental regulations?

A: Yes. The MMBTH81 is ROHS3 compliant. The CMPTH81 TR compliance status was not specified in available documentation.

Q: Are there any electrical performance differences?

A: No. All specified electrical parameters are identical: 20V breakdown voltage, 600MHz transition frequency, 225mW maximum power, 60 minimum hFE at 5mA/10V, 50mA maximum collector current, and -55°C to 150°C operating range.