BC558C Equivalent & Substitute Parts

Part Overview

The BC558C is a PNP bipolar junction transistor manufactured by onsemi, housed in a TO-92-3 through-hole package. This device is rated for 30 V collector-emitter breakdown voltage, 100 mA maximum collector current, and 500 mW power dissipation. The BC558C operates at a transition frequency of 150 MHz with a maximum junction temperature of 150°C.

The BC558C is classified as an obsolete product. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure component availability, and support ongoing production or repair requirements for legacy systems utilizing this transistor.

Substiute Parts

BC558C

onsemiIn Stock: 5312BC558C Datasheet

Current PartRFQ

BC559CTA

onsemiIn Stock: 70031BC559CTA Datasheet

DirectRFQ

BC556BTF

onsemiIn Stock: 24196BC556BTF Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the BC558C is determined by electrical and mechanical compatibility across the following critical parameters:

Electrical Compatibility Criteria:

• Transistor type must be PNP
• Maximum collector current (Ic) must be ≥ 100 mA
• Collector-emitter breakdown voltage (Vce breakdown) must be ≥ 30 V
• Vce saturation characteristics must match or be superior
• DC current gain (hFE) must meet or exceed minimum specifications
• Power dissipation rating must be ≥ 500 mW
• Transition frequency must be ≥ 150 MHz
• Maximum junction temperature must be ≥ 150°C

Mechanical Compatibility Criteria:

• Package type must be TO-92-3 through-hole configuration
• Lead configuration must support through-hole mounting

Substitute parts are grouped into two categories:

Direct Substitutes: Parts that match all electrical parameters of the BC558C while maintaining identical or superior performance characteristics.

Similar Substitutes: Parts that exceed one or more electrical parameters (such as voltage rating) while maintaining functional compatibility within the same package and mounting configuration.

Parameter Comparison

Engineering Selection Recommendations

BC559CTA (Direct Substitute):

The BC559CTA is a direct electrical equivalent to the BC558C. Both devices share identical maximum ratings for collector current (100 mA), collector-emitter breakdown voltage (30 V), saturation voltage characteristics, cutoff current, DC current gain, power dissipation (500 mW), transition frequency (150 MHz), and operating temperature (150°C). Both are housed in the TO-92-3 through-hole package with identical lead configuration.

The BC559CTA is classified as an active product with ROHS3 compliance and is available in high inventory quantities (69,987 pieces). This part is suitable for direct replacement in applications where the BC558C was originally specified.

BC556BTF (Similar Substitute):

The BC556BTF is a similar substitute with enhanced voltage rating. This device maintains all electrical parameters identical to the BC558C except for the collector-emitter breakdown voltage, which is rated at 65 V compared to 30 V. The DC current gain (hFE) is lower at 200 (minimum) versus 420 (minimum) for the BC558C.

The BC556BTF is classified as an active product with ROHS3 compliance and is available in inventory (24,146 pieces). This part is suitable for applications where the original 30 V rating is not a limiting constraint and where the lower DC current gain is acceptable for the circuit design.

Both substitute parts are manufactured by onsemi, share identical package configurations, and maintain through-hole mounting compatibility with the BC558C.

Frequently Asked Questions (FAQ)

Q: Can the BC559CTA be used as a direct replacement for the BC558C?

A: Yes. The BC559CTA is a direct electrical equivalent with identical electrical specifications across all critical parameters: collector current (100 mA), collector-emitter breakdown voltage (30 V), saturation voltage, cutoff current, DC current gain (420 minimum), power dissipation (500 mW), transition frequency (150 MHz), and operating temperature (150°C). Both devices use the TO-92-3 through-hole package. The BC559CTA is an active product with current availability.

Q: What is the difference between the BC559CTA and BC556BTF?

A: The primary difference is the collector-emitter breakdown voltage rating. The BC559CTA is rated for 30 V (matching the BC558C), while the BC556BTF is rated for 65 V. Additionally, the BC556BTF has a lower DC current gain (200 minimum) compared to the BC559CTA and BC558C (420 minimum). Both devices share identical collector current, saturation voltage, power dissipation, transition frequency, and operating temperature ratings.

Q: Can the BC556BTF be used in place of the BC558C?

A: The BC556BTF is electrically compatible with the BC558C in applications where the circuit operates below 30 V and where the lower DC current gain (200 versus 420) does not compromise circuit performance. The higher voltage rating of the BC556BTF (65 V) provides additional design margin in higher-voltage applications. Circuit validation is necessary to confirm suitability for specific applications.

Q: Are all three parts housed in the same package?

A: Yes. The BC558C, BC559CTA, and BC556BTF are all housed in the TO-92-3 through-hole package with identical lead configuration and mounting requirements.

Q: What is the product status of each part?

A: The BC558C is classified as obsolete. Both the BC559CTA and BC556BTF are classified as active products with current manufacturing and availability.

Q: Are the substitute parts RoHS compliant?

A: The BC559CTA and BC556BTF are both ROHS3 compliant. The BC558C product status documentation does not specify RoHS compliance status.

Q: What are the inventory levels for each part?

A: The BC558C has 5,300 pieces in stock. The BC559CTA has 69,987 pieces in stock. The BC556BTF has 24,146 pieces in stock.