MMBTH34 Equivalent & Substitute Parts Reference

Part Overview

The MMBTH34 is an RF transistor NPN type manufactured by onsemi, rated for 40V collector-emitter breakdown voltage with a 500MHz transition frequency and 225mW maximum power dissipation in a surface mount SOT-23-3 package. This part is classified as obsolete, necessitating identification of equivalent substitute components for new designs and ongoing production requirements. Substitute parts must maintain electrical compatibility within the specified parameter ranges while meeting current product status and compliance requirements.

Substiute Parts

MMBTH34

onsemiIn Stock: 33134MMBTH34 Datasheet

Current PartRFQ

MMBT3416LT3G

onsemiIn Stock: 8310MMBT3416LT3G Datasheet

SimilarRFQ

MMBT6429LT1G

onsemiIn Stock: 155261MMBT6429LT1G Datasheet

SimilarRFQ

BSS64,215

Nexperia USA Inc.In Stock: 4187BSS64,215 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the MMBTH34 is determined by the following criteria:

Primary Compatibility Requirements:

• Transistor Type: NPN (mandatory match)
• Package / Case: SOT-23-3 surface mount (mandatory match)
• Operating Temperature Range: -55°C to 150°C (mandatory match)
• Moisture Sensitivity Level: 1 (Unlimited) (mandatory match)

Electrical Parameter Compatibility:

• Voltage - Collector Emitter Breakdown (Max): Must equal or exceed 40V
• Current - Collector (Ic) (Max): Must equal or exceed 50mA
• Power - Max: Must equal or exceed 225mW
• Frequency - Transition: Must equal or exceed 500MHz (where specified)

The three identified substitute parts meet these criteria with the following characteristics:

MMBT3416LT3G (onsemi): Active product status. Exceeds current rating (100mA vs. 50mA). Matches voltage (40V) and power (225mW). Transition frequency not specified. DC current gain differs (75 @ 2mA, 4.5V vs. 15 @ 20mA, 2V).

MMBT6429LT1G (onsemi): Active product status. Exceeds voltage (45V vs. 40V), current (200mA vs. 50mA), and frequency (700MHz vs. 500MHz). Matches power (225mW). DC current gain significantly higher (500 @ 100µA, 5V).

BSS64,215 (Nexperia USA Inc.): Not For New Designs status. Exceeds voltage (80V vs. 40V) and current (100mA vs. 50mA). Frequency lower (100MHz vs. 500MHz). Power slightly higher (250mW vs. 225mW). Automotive qualified (AEC-Q101).

Parameter Comparison

Engineering Selection Recommendations

For New Designs:

MMBT6429LT1G is the primary recommended substitute. This part is active product status, ROHS3 compliant, and manufactured by onsemi (original MMBTH34 manufacturer). It exceeds all electrical parameters of the MMBTH34, including voltage (45V), current (200mA), and frequency (700MHz), providing design margin. The higher DC current gain (500 @ 100µA, 5V) may require circuit verification if the original design relied on specific gain characteristics.

MMBT3416LT3G is an alternative active product from onsemi. It matches the voltage and power specifications exactly (40V, 225mW) and doubles the current capability (100mA vs. 50mA). Transition frequency is not specified; this parameter must be verified against application requirements before selection.

For Existing Production:

BSS64,215 is not recommended for new designs due to its "Not For New Designs" status. However, it remains available for legacy production support with 4,100 pieces in stock. This part is automotive qualified (AEC-Q101) and suitable only for applications where the lower transition frequency (100MHz) is acceptable. The significantly higher voltage rating (80V) introduces design margin but may not be necessary for 40V applications.

Compliance Considerations:

All three substitute parts are ROHS3 compliant and REACH unaffected. MMBT6429LT1G and MMBT3416LT3G are preferred for new designs based on active product status and full compliance documentation.

Frequently Asked Questions (FAQ)

Q: Can MMBT3416LT3G replace MMBTH34 in RF applications?

A: MMBT3416LT3G is electrically compatible for voltage (40V) and power (225mW) parameters. However, transition frequency is not specified for this part. RF applications operating at 500MHz require verification that MMBT3416LT3G meets frequency performance requirements before implementation.

Q: What is the primary advantage of MMBT6429LT1G over MMBTH34?

A: MMBT6429LT1G is an active product with higher performance margins across all parameters: 45V voltage (vs. 40V), 200mA current (vs. 50mA), and 700MHz frequency (vs. 500MHz). It provides design margin for applications requiring the MMBTH34 specification while ensuring long-term supply availability.

Q: Why is BSS64,215 marked "Not For New Designs"?

A: BSS64,215 carries a "Not For New Designs" status from Nexperia, indicating the manufacturer does not recommend this part for new circuit development. It remains available for legacy production support only. New designs should use MMBT6429LT1G or MMBT3416LT3G.

Q: Are all substitute parts in the same SOT-23-3 package?

A: Yes. MMBTH34, MMBT3416LT3G, MMBT6429LT1G, and BSS64,215 are all surface mount SOT-23-3 (TO-236-3, SC-59) packages. Pin-for-pin compatibility is maintained across all substitutes.

Q: What is the difference in DC current gain between MMBTH34 and the substitutes?

A: MMBTH34 specifies 15 @ 20mA, 2V. MMBT3416LT3G specifies 75 @ 2mA, 4.5V (higher gain at lower current). MMBT6429LT1G specifies 500 @ 100µA, 5V (significantly higher gain at very low current). BSS64,215 specifies 20 @ 10mA, 1V (similar to MMBTH34). Gain differences may affect circuit biasing and require design verification.

Q: Which substitute has the longest supply availability?

A: MMBT6429LT1G has the highest inventory (155,200 pieces) and active product status, ensuring long-term availability. MMBT3416LT3G has 8,200 pieces in stock and active status. BSS64,215 has 4,100 pieces but "Not For New Designs" status, indicating limited future availability.

Q: Can BSS64,215 be used in automotive applications?

A: BSS64,215 is AEC-Q101 qualified and suitable for automotive applications. However, its "Not For New Designs" status and lower transition frequency (100MHz vs. 500MHz) make it unsuitable for new automotive designs requiring RF performance at 500MHz.