2SC3929ASL Equivalent & Substitute Parts

Part Overview

The 2SC3929ASL is an NPN bipolar junction transistor manufactured by Panasonic Electronic Components, designed for surface mount applications in the SC-70/SOT-323 package. This device operates at a maximum collector voltage of 55 V with a collector current rating of 50 mA and a maximum power dissipation of 150 mW. The 2SC3929ASL is classified as obsolete, making identification of functionally equivalent substitute components necessary for ongoing design support and production continuity.

Substiute Parts

2SC3929ASL

Panasonic Electronic ComponentsIn Stock: 8032SC3929ASL Datasheet

Current PartRFQ

BC847CW-TP

Micro Commercial CoIn Stock: 5000392BC847CW-TP Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the obsolete 2SC3929ASL is based on the following critical electrical and mechanical parameters:

Electrical Compatibility Criteria:

• Transistor polarity: NPN type required
• Collector-emitter breakdown voltage: Substitute must equal or exceed 55 V
• Maximum collector current: Substitute must equal or exceed 50 mA
• Maximum power dissipation: Substitute must equal or exceed 150 mW
• Transition frequency: Substitute must equal or exceed 100 MHz
• DC current gain (hFE): Substitute must meet or exceed 260 @ 2mA, 5V
• Saturation voltage: Substitute must not exceed 600 mV @ specified test conditions

Mechanical Compatibility Criteria:

• Package type: SC-70 or SOT-323 surface mount package required
• Moisture sensitivity level: MSL 1 (Unlimited) acceptable
• Operating temperature range: Must support maximum junction temperature of 150°C

The BC847CW-TP satisfies substitution requirements through electrical parameter equivalence and package compatibility, despite differences in absolute maximum ratings.

Parameter Comparison

Engineering Selection Recommendations

The BC847CW-TP is a functionally equivalent substitute for the obsolete 2SC3929ASL based on the following engineering criteria:

Electrical Equivalence: The BC847CW-TP meets or exceeds all critical electrical parameters of the 2SC3929ASL. The collector current rating of 100 mA exceeds the 50 mA requirement. The transition frequency of 100 MHz matches the original specification. The DC current gain of 420 @ 2mA, 5V exceeds the minimum requirement of 260. Saturation voltage remains at 600 mV, maintaining switching performance characteristics.

Voltage Rating Consideration: The BC847CW-TP has a collector-emitter breakdown voltage of 45 V, which is 10 V lower than the 2SC3929ASL specification of 55 V. This difference requires circuit-level voltage margin analysis. Applications operating at voltages below 45 V are directly compatible. Applications requiring the full 55 V rating require alternative substitutes or circuit redesign.

Package and Mounting Compatibility: Both devices use the SC-70/SOT-323 surface mount package, ensuring mechanical and thermal compatibility on existing printed circuit boards without layout modification.

Product Status and Compliance: The BC847CW-TP is an active product with ROHS3 compliance and REACH unaffected status, providing long-term supply availability and regulatory compliance advantages over the obsolete 2SC3929ASL.

Moisture Sensitivity: Both devices carry MSL 1 (Unlimited) rating, indicating no moisture sensitivity constraints during storage or handling.

Frequently Asked Questions (FAQ)

Q: Can the BC847CW-TP directly replace the 2SC3929ASL in all applications?

A: Direct replacement is possible in applications where the circuit operates at collector-emitter voltages of 45 V or below. The BC847CW-TP has a 45 V breakdown voltage compared to the 2SC3929ASL specification of 55 V. Applications requiring operation above 45 V require circuit redesign or alternative substitute selection.

Q: What are the key electrical differences between these devices?

A: The BC847CW-TP provides higher collector current capacity (100 mA versus 50 mA) and higher DC current gain (420 versus 260 minimum). Both devices share identical transition frequency (100 MHz) and saturation voltage (600 mV). The primary limitation is the reduced breakdown voltage of the BC847CW-TP.

Q: Are the packages physically identical?

A: Yes. Both the 2SC3929ASL and BC847CW-TP use the SC-70/SOT-323 surface mount package. No PCB layout modifications are required for physical substitution.

Q: What is the moisture sensitivity rating for the BC847CW-TP?

A: The BC847CW-TP carries an MSL 1 (Unlimited) rating, identical to the 2SC3929ASL. This indicates no moisture sensitivity constraints and no special storage or handling requirements.

Q: Is the BC847CW-TP RoHS compliant?

A: Yes. The BC847CW-TP is ROHS3 compliant and REACH unaffected, meeting current environmental and regulatory requirements.

Q: What is the operating temperature range of the BC847CW-TP?

A: The BC847CW-TP operates from −65°C to 150°C junction temperature, supporting the full 150°C maximum operating temperature of the 2SC3929ASL.

Q: How does the DC current gain comparison affect circuit design?

A: The BC847CW-TP minimum DC current gain of 420 @ 2mA, 5V exceeds the 2SC3929ASL specification of 260. This higher gain provides improved switching speed and reduced base drive requirements in switching applications. Circuits designed for the lower gain of the 2SC3929ASL will operate with improved performance margins using the BC847CW-TP.

Q: What is the collector cutoff current difference?

A: The BC847CW-TP has a maximum collector cutoff current of 100 nA compared to 1 µA for the 2SC3929ASL. This lower leakage current in the BC847CW-TP provides improved off-state performance in low-power applications.