2SC5171,Q(J Equivalent & Substitute Parts

Part Overview

The 2SC5171,Q(J is an NPN bipolar junction transistor manufactured by Toshiba Semiconductor and Storage, designed for general-purpose switching and amplification applications. This device features a maximum collector current of 2 A, collector-emitter breakdown voltage of 180 V, and maximum power dissipation of 2 W in a TO-220NIS package configuration. The product is currently classified as obsolete, making identification of functionally equivalent alternatives necessary for ongoing system support and new design implementations.

Substiute Parts

2SC5171,Q(J

Toshiba Semiconductor and StorageIn Stock: 10732SC5171,Q(J Datasheet

Current PartRFQ

TTC004B,Q

Toshiba Semiconductor and StorageIn Stock: 924TTC004B,Q Datasheet

SimilarRFQ

2SC4381

Sanken Electric USA Inc.In Stock: 19462SC4381 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 2SC5171,Q(J requires evaluation against the following critical electrical and mechanical parameters:

Electrical Compatibility Criteria:

• Transistor type must be NPN
• Collector current rating must equal or exceed 2 A
• Collector-emitter breakdown voltage must equal or exceed 180 V
• Power dissipation capability must support application requirements
• DC current gain characteristics must be compatible with circuit biasing

Mechanical Compatibility Criteria:

• Through-hole mounting configuration
• Package form factor compatibility with PCB layout

The substitute parts identified below meet these criteria within the constraints of their respective electrical specifications and package configurations.

Parameter Comparison

Engineering Selection Recommendations

2SC4381 (Sanken Electric USA Inc.)

The 2SC4381 is an active product offering identical collector current rating (2 A) and superior power dissipation capability (25 W versus 2 W). The device maintains TO-220-3 package compatibility with the original 2SC5171,Q(J. However, the collector-emitter breakdown voltage is reduced to 150 V, which represents a 30 V reduction from the original specification. This device is ROHS3 compliant and carries active product status, ensuring long-term availability and supply chain stability.

TTC004B,Q (Toshiba Semiconductor and Storage)

The TTC004B,Q is an active product with higher DC current gain (140 versus 100) and superior power dissipation (10 W versus 2 W). The device exhibits lower collector cutoff current (100 nA versus 5µA), indicating reduced leakage characteristics. However, this substitute presents two significant deviations: collector current is limited to 1.5 A (25% reduction), and collector-emitter breakdown voltage is 160 V (20 V reduction). The package configuration changes to TO-126-3, requiring PCB layout modification. This device is RoHS compliant and maintains active product status.

Both substitute parts are manufactured by established semiconductor suppliers with active product designations, ensuring continued availability and technical support.

Frequently Asked Questions (FAQ)

Q: Can the TTC004B,Q be used as a direct replacement for the 2SC5171,Q(J?

A: The TTC004B,Q is not a direct replacement. While both are NPN transistors with through-hole mounting, the TTC004B,Q has a maximum collector current of 1.5 A compared to 2 A for the original device. Additionally, the package changes from TO-220-3 to TO-126-3, requiring PCB modification. The collector-emitter breakdown voltage is also reduced to 160 V. Use this substitute only when application current requirements do not exceed 1.5 A and the reduced voltage rating is acceptable.

Q: Is the 2SC4381 a suitable alternative for high-voltage applications?

A: The 2SC4381 maintains the same collector current rating (2 A) and package form factor (TO-220-3) as the original 2SC5171,Q(J. However, the maximum collector-emitter breakdown voltage is 150 V, which is 30 V lower than the original specification. Applications requiring the full 180 V rating cannot use this substitute. Verify that your circuit operates within the 150 V maximum rating before selection.

Q: What are the package differences between these substitutes?

A: The 2SC5171,Q(J and 2SC4381 both use TO-220-3 packages, which are mechanically and electrically compatible. The TTC004B,Q uses a TO-126-3 package, which is physically smaller and requires different PCB footprint and mounting hole spacing. Thermal management characteristics also differ between TO-220 and TO-126 packages due to different lead configurations and heat dissipation paths.

Q: How do the DC current gain characteristics compare?

A: The 2SC5171,Q(J specifies a minimum hFE of 100 at 100 mA collector current and 5 V collector-emitter voltage. The TTC004B,Q provides higher gain (140 minimum at the same conditions), while the 2SC4381 specifies lower gain (60 minimum, but measured at different conditions: 700 mA and 10 V). Circuit biasing networks may require adjustment when substituting between these devices due to gain variations.

Q: Are there compliance or supply chain advantages to using the substitute parts?

A: Both substitute parts carry active product status, ensuring continued manufacturing and availability. The 2SC4381 is ROHS3 compliant, and the TTC004B,Q is RoHS compliant. The original 2SC5171,Q(J is classified as obsolete, making long-term supply uncertain. For new designs or systems requiring extended product life, the active substitutes provide superior supply chain reliability.

Q: What is the impact of reduced collector-emitter breakdown voltage on circuit design?

A: Collector-emitter breakdown voltage represents the maximum voltage that can be applied between collector and emitter without device failure. The 2SC5171,Q(J rating of 180 V provides a safety margin for circuits operating at high voltages. The 2SC4381 (150 V) and TTC004B,Q (160 V) have reduced margins. Verify that your circuit's maximum operating voltage, including transient overvoltage conditions, remains below the substitute device's rating.