FMMT6517TC Equivalent & Substitute Parts

Part Overview

The FMMT6517TC is an NPN bipolar junction transistor manufactured by Diodes Incorporated, designed for surface mount applications in the SOT-23-3 package. This device operates at 350 V collector-emitter breakdown voltage with a maximum collector current of 500 mA and a power dissipation rating of 330 mW. The FMMT6517TC is classified as obsolete, necessitating identification of active equivalent and substitute components for new designs and ongoing production requirements. Substitute parts must maintain electrical and mechanical compatibility within the specified parameter ranges.

Key Parameters

Parameter	Value	Unit
Transistor Type	NPN	—
Collector-Emitter Breakdown Voltage (Max)	350	V
Collector Current (Max)	500	mA
Power Dissipation (Max)	330	mW
Transition Frequency	50	MHz
DC Current Gain (hFE Min)	20	@ 50mA, 10V
Vce Saturation (Max)	1	V @ 5mA, 50mA
Operating Temperature Range	-55 to 150	°C
Package Type	SOT-23-3	—
Mounting Type	Surface Mount	—

Substitute Part Grouping Explanation

Substitute parts for the FMMT6517TC are classified into two categories based on electrical parameter alignment:

Category 1: Direct Parametric Equivalents These parts maintain identical or equivalent electrical specifications across all critical parameters: 350 V collector-emitter breakdown voltage, 500 mA maximum collector current, 50 MHz transition frequency, and compatible saturation characteristics. Parts in this category are interchangeable for applications requiring the full electrical specification of the original device.

Category 2: Functional Alternatives These parts satisfy the core application requirements but differ in one or more secondary parameters such as transition frequency, power dissipation, or collector current rating. Selection from this category requires verification that the application does not depend on the differing parameters.

The following parameters determine substitution eligibility:

Collector-Emitter Breakdown Voltage (must be ≥350 V)
Collector Current Rating (must be ≥500 mA)
Package Type (must be SOT-23-3 or compatible)
Transistor Type (must be NPN)
RoHS and REACH compliance status

Parameter Comparison

Part Number	Manufacturer	Status	Vce(BR) (V)	Ic(Max) (mA)	Power (mW)	fT (MHz)	hFE(Min)	Package
FMMT6517TC	Diodes Incorporated	Obsolete	350	500	330	50	20	SOT-23-3
DN350T05-7	Diodes Incorporated	Active	350	500	300	50	20	SOT-23-3
FMMT6517TA	Diodes Incorporated	Active	350	500	330	50	20	SOT-23-3
CMPT6517 TR PBFREE	Central Semiconductor Corp	Active	350	500	350	200	20	SOT-23-3
FJV42MTF	onsemi	Active	350	500	350	50	40	SOT-23-3
BF820,215	Nexperia USA Inc.	Active	300	50	250	60	50	TO-236AB
CMPTA46 TR PBFREE	Central Semiconductor Corp	Active	450	500	350	20	50	SOT-23-3
MMBT2484LT1G	onsemi	Active	60	100	225	—	250	SOT-23-3
MMBT2484LT3G	onsemi	Active	60	100	225	—	250	SOT-23-3
MMBT6429LT1G	onsemi	Active	45	200	225	700	500	SOT-23-3
MMBTA42,215	Nexperia USA Inc.	Active	300	100	250	50	40	TO-236AB

Engineering Selection Recommendations

Primary Recommendation: FMMT6517TA The FMMT6517TA is the preferred substitute for the obsolete FMMT6517TC. Manufactured by Diodes Incorporated, this part maintains identical electrical specifications including 350 V breakdown voltage, 500 mA collector current, 330 mW power dissipation, and 50 MHz transition frequency. The FMMT6517TA is classified as active with ROHS3 compliance and unlimited moisture sensitivity level (MSL 1). This part provides direct functional replacement with no parameter derating required.

Secondary Recommendation: DN350T05-7 The DN350T05-7 from Diodes Incorporated is an active alternative with equivalent voltage and current ratings. This part differs only in power dissipation (300 mW versus 330 mW), which represents a 9% reduction. Applications operating below the thermal limits of the original device accept this substitute. DN350T05-7 is supplied in tape and reel packaging and maintains full ROHS3 compliance.

Alternative Recommendation: FJV42MTF The FJV42MTF manufactured by onsemi meets the 350 V breakdown voltage and 500 mA collector current requirements. This part features enhanced DC current gain (hFE minimum of 40 versus 20) and increased power dissipation (350 mW). The FJV42MTF is suitable for applications where higher current gain provides design margin. Active product status and ROHS3 compliance are confirmed.

Higher Voltage Alternative: CMPTA46 TR PBFREE The CMPTA46 from Central Semiconductor Corp provides 450 V breakdown voltage with 500 mA collector current capability. This part is suitable for applications requiring voltage margin above 350 V. The transition frequency is reduced to 20 MHz. Active status and ROHS3 compliance are maintained.

Not Recommended for Direct Substitution: The parts BF820,215, MMBT2484LT1G, MMBT2484LT3G, MMBT6429LT1G, and MMBTA42,215 do not meet the minimum electrical requirements of the FMMT6517TC. These devices feature reduced collector current ratings (50-200 mA) or breakdown voltages (45-300 V) that fall below the original specification. These parts are suitable only for applications with lower voltage or current requirements.

Frequently Asked Questions (FAQ)

Q: Can the FMMT6517TC be replaced with the FMMT6517TA in existing designs? A: Yes. The FMMT6517TA is a direct parametric equivalent with identical electrical specifications. No circuit modifications are required. Both parts are manufactured by Diodes Incorporated and share the same base product number (FMMT6517), differing only in packaging configuration (TC is cut tape, TA is tape and reel).

Q: What is the difference between DN350T05-7 and FMMT6517TA? A: Both parts meet the 350 V, 500 mA, and 50 MHz specifications. The DN350T05-7 has a maximum power dissipation of 300 mW compared to 330 mW for the FMMT6517TA. Applications with thermal constraints below 300 mW should use the FMMT6517TA. Both are active products from Diodes Incorporated.

Q: Is the FJV42MTF a suitable replacement for high-current applications? A: The FJV42MTF meets the 500 mA collector current and 350 V breakdown voltage requirements. The higher DC current gain (40 versus 20) provides additional design margin in current-limited circuits. The 350 mW power rating exceeds the original specification. This part is suitable for applications where the enhanced gain characteristic is beneficial.

Q: Why are MMBT2484 and MMBT6429 devices not recommended? A: These parts have collector current ratings of 100 mA and 200 mA respectively, which fall below the 500 mA requirement of the FMMT6517TC. Additionally, the MMBT2484 has a 60 V breakdown voltage and the MMBT6429 has a 45 V breakdown voltage, both significantly below the 350 V specification. These devices are suitable only for low-voltage, low-current applications.

Q: What packaging options are available for substitutes? A: The FMMT6517TC is supplied in SOT-23-3 package. Direct substitutes FMMT6517TA, DN350T05-7, CMPT6517, FJV42MTF, and CMPTA46 are also available in SOT-23-3 package. The BF820,215 and MMBTA42,215 are supplied in TO-236AB package, which is mechanically compatible with SOT-23-3 but may require PCB layout verification. Consult component datasheets for precise package dimensions.

Q: Are all substitute parts RoHS3 compliant? A: Yes. All substitute parts listed in this reference are ROHS3 compliant. The FMMT6517TC original part is also ROHS3 compliant. REACH status is unaffected for all parts. Moisture sensitivity level (MSL) is 1 (unlimited) for all parts, indicating no special storage or handling requirements.

Q: Can CMPTA46 be used in place of FMMT6517TC for voltage margin? A: The CMPTA46 provides 450 V breakdown voltage, which exceeds the 350 V requirement. This part is suitable for applications where additional voltage margin is required. However, the transition frequency is reduced to 20 MHz from the original 50 MHz. Applications sensitive to frequency response should verify compatibility before substitution.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message