BC547B-AP Equivalent & Substitute Parts

Part Overview

The BC547B-AP is an NPN bipolar junction transistor manufactured by Micro Commercial Co, designed for small-signal amplification and switching applications. Specified for 45 V collector-emitter breakdown voltage and 100 mA maximum collector current, this component operates across a wide temperature range from -55°C to 150°C. The part is classified as obsolete, necessitating identification of active equivalent alternatives that maintain electrical and mechanical compatibility for ongoing production and maintenance applications.

Key Parameters

Parameter	Value	Unit
Transistor Type	NPN	—
Current - Collector (Ic) Max	100	mA
Voltage - Collector Emitter Breakdown (Max)	45	V
Vce Saturation (Max) @ Ib, Ic	300 mV @ 5 mA, 100 mA	—
DC Current Gain (hFE) Min @ Ic, Vce	200 @ 2 mA, 5 V	—
Power - Max	625	mW
Frequency - Transition	300	MHz
Operating Temperature	-55 to 150	°C
Mounting Type	Through Hole	—
Package / Case	TO-92-3 (TO-226AA)	—
RoHS Status	ROHS3 Compliant	—
Moisture Sensitivity Level	1 (Unlimited)	—

Substitute Part Grouping Explanation

Substitution of the BC547B-AP is determined by strict electrical and mechanical parameter matching within the NPN small-signal transistor category. The critical parameters governing substitution eligibility are:

Electrical Compatibility Requirements:

Transistor type must be NPN
Collector-emitter breakdown voltage (VCEO) must equal or exceed 45 V
Maximum collector current (Ic) must be 100 mA or greater
DC current gain (hFE) minimum must be 200 or higher at specified test conditions
Transition frequency must be 300 MHz or greater
Maximum power dissipation must support 625 mW or greater

Mechanical Compatibility Requirements:

Package type must be TO-92-3 (TO-226AA) through-hole configuration
Lead formation must be compatible with standard PCB layouts

Compliance Requirements:

RoHS3 compliance required
REACH unaffected status required

Substitute parts are classified into two categories:

Direct Substitutes maintain identical electrical specifications to the BC547B-AP while differing only in manufacturer, packaging format, or product status (active vs. obsolete).

Similar Substitutes meet all minimum electrical requirements but may exhibit higher DC current gain (hFE) or different saturation characteristics, remaining functionally compatible within the specified parameter envelope.

Parameter Comparison

Parameter	BC547B-AP (Main)	BC546-AP	BC547BTA	BC547BTF	BC550CTA
Manufacturer	Micro Commercial Co	Micro Commercial Co	Fairchild Semiconductor	onsemi	onsemi
Product Status	Obsolete	Active	Active	Active	Active
Transistor Type	NPN	NPN	NPN	NPN	NPN
Ic (Max)	100 mA	100 mA	100 mA	100 mA	100 mA
VCEO (Max)	45 V	65 V	45 V	45 V	45 V
Vce Saturation (Max) @ 5mA, 100mA	300 mV	300 mV	600 mV	600 mV	600 mV
hFE (Min) @ 2mA, 5V	200	200	200	200	420
Power (Max)	625 mW	625 mW	625 mW	500 mW	500 mW
Frequency - Transition	300 MHz	300 MHz	300 MHz	300 MHz	300 MHz
Operating Temperature	-55 to 150°C	-55 to 150°C	-55 to 150°C	-55 to 150°C	-55 to 150°C
Package / Case	TO-92-3	TO-92-3	TO-92-3	TO-92-3	TO-92-3
RoHS Status	ROHS3 Compliant	ROHS3 Compliant	Not specified	ROHS3 Compliant	ROHS3 Compliant
Inventory Status	2040 Pcs	1054 Pcs	1308 Pcs	22801 Pcs	13720 Pcs

Engineering Selection Recommendations

BC547BTA (Fairchild Semiconductor) and BC547BTF (onsemi) are direct electrical equivalents to the BC547B-AP, maintaining identical collector-emitter breakdown voltage (45 V) and minimum DC current gain (200). Both parts are active products with confirmed RoHS3 compliance. BC547BTF offers the highest inventory availability (22,801 units) and is supplied in cut tape packaging. BC547BTA is supplied in bulk packaging. Both support the full operating temperature range and TO-92-3 package configuration.

BC550CTA (onsemi) meets all minimum electrical requirements with identical voltage and current ratings. This part exhibits higher DC current gain (420 minimum vs. 200 minimum), which may affect circuit biasing characteristics in gain-sensitive applications. BC550CTA is active, RoHS3 compliant, and maintains TO-92-3 package compatibility with substantial inventory availability (13,720 units).

BC546-AP (Micro Commercial Co) is an active alternative from the same manufacturer as the original part. This transistor features higher collector-emitter breakdown voltage (65 V) and identical current/gain specifications. BC546-AP is suitable for applications requiring enhanced voltage margin while maintaining electrical compatibility in the TO-92-3 package.

All substitute parts are through-hole mounted components compatible with standard PCB assembly processes. Selection should prioritize active products with confirmed RoHS3 compliance and adequate inventory for production requirements.

Frequently Asked Questions (FAQ)

Q: Can BC547BTF directly replace BC547B-AP in existing circuit designs?

A: Yes. BC547BTF maintains identical electrical specifications for collector-emitter breakdown voltage (45 V), maximum collector current (100 mA), and minimum DC current gain (200). Both components use the TO-92-3 package with compatible lead formation. No circuit modifications are required.

Q: What is the difference between BC547BTA and BC547BTF?

A: Both parts are electrically identical BC547B equivalents from onsemi. The primary difference is packaging format: BC547BTA is supplied in bulk packaging, while BC547BTF is supplied in cut tape. Selection depends on assembly process requirements and handling procedures.

Q: Why does BC550CTA have higher DC current gain (420 vs. 200)?

A: BC550CTA is a higher-gain variant within the BC550 series. While it meets all minimum electrical requirements for BC547B-AP substitution, the elevated hFE may alter circuit biasing and gain characteristics. Verification of circuit performance is necessary when substituting with higher-gain devices in sensitive applications.

Q: Is BC546-AP suitable as a substitute despite higher VCEO rating?

A: Yes. BC546-AP exceeds the minimum collector-emitter breakdown voltage requirement (65 V vs. 45 V required). This provides additional voltage margin and is electrically compatible. The higher voltage rating does not compromise functionality in circuits designed for 45 V operation.

Q: Are all substitute parts RoHS3 compliant?

A: BC547BTF, BC550CTA, and BC546-AP are confirmed ROHS3 compliant. BC547BTA compliance status is not specified in available documentation. Verification with the supplier is recommended for applications with strict RoHS compliance requirements.

Q: What is the significance of the TO-92-3 package specification?

A: TO-92-3 is the three-lead through-hole package configuration used by all listed parts. This ensures mechanical and electrical compatibility with existing PCB layouts designed for BC547B-AP. Lead spacing and pin assignment are identical across all substitute parts.

Q: Can BC547B-AP be used interchangeably with BC546-AP in the same circuit?

A: Yes, within voltage constraints. BC546-AP operates at higher collector-emitter breakdown voltage (65 V) but maintains identical current and gain specifications. Circuits designed for 45 V operation function correctly with BC546-AP, which provides additional voltage headroom.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message