BC327,412 Equivalent & Substitute Parts

Part Overview

The BC327,412 is a PNP bipolar junction transistor manufactured by NXP USA Inc., designed for general-purpose switching and amplification applications. This device features a 45 V collector-emitter breakdown voltage, 500 mA maximum collector current, and 625 mW power dissipation capability in a TO-92-3 through-hole package. The BC327,412 is classified as obsolete, necessitating identification of active alternative components that maintain functional compatibility within existing circuit designs. Substitute parts must satisfy the electrical and mechanical requirements of the original specification while offering current availability and active product status.

Key Parameters

Parameter	BC327,412 Specification
Transistor Type	PNP
Voltage - Collector Emitter Breakdown (Max)	45 V
Current - Collector (Ic) (Max)	500 mA
Power - Max	625 mW
Frequency - Transition	80 MHz
DC Current Gain (hFE) (Min) @ Ic, Vce	100 @ 100mA, 1V
Vce Saturation (Max) @ Ib, Ic	700mV @ 50mA, 500mA
Mounting Type	Through Hole
Package / Case	TO-92-3 (TO-226AA)
Operating Temperature (Max)	150°C (TJ)

Substitute Part Grouping Explanation

Substitution of the BC327,412 is determined by the following critical parameters:

Mandatory Compatibility Criteria:

Transistor Type: PNP (all substitutes must be PNP)
Package / Case: TO-92-3 through-hole configuration (mechanical and pin compatibility)
Mounting Type: Through Hole (circuit board assembly compatibility)
Power - Max: 625 mW (thermal dissipation capability)
Operating Temperature: 150°C maximum junction temperature

Functional Compatibility Criteria:

Voltage - Collector Emitter Breakdown (Max): Must equal or exceed 45 V
Current - Collector (Ic) (Max): Must equal or exceed 500 mA
Frequency - Transition: Must support the application frequency requirements
DC Current Gain (hFE): Must meet or exceed minimum gain specifications
Vce Saturation: Must be compatible with circuit switching requirements

All identified substitute parts satisfy the mandatory mechanical and thermal requirements. Functional compatibility is determined by whether each substitute meets or exceeds the electrical performance envelope of the BC327,412 within the specified operating conditions.

Parameter Comparison

Parameter	BC327,412	2N3906BU	2N4403BU	BC32725BU	BC32740BU	PN2907BU
Manufacturer	NXP USA Inc.	Fairchild Semiconductor	Fairchild Semiconductor	onsemi	onsemi	Fairchild Semiconductor
Product Status	Obsolete	Active	Active	Active	Active	Active
Transistor Type	PNP	PNP	PNP	PNP	PNP	PNP
Voltage - Collector Emitter Breakdown (Max)	45 V	40 V	40 V	45 V	45 V	40 V
Current - Collector (Ic) (Max)	500 mA	200 mA	600 mA	800 mA	800 mA	800 mA
Power - Max	625 mW	625 mW	625 mW	625 mW	625 mW	625 mW
Frequency - Transition	80 MHz	250 MHz	200 MHz	100 MHz	100 MHz	Not Specified
DC Current Gain (hFE) (Min)	100 @ 100mA, 1V	100 @ 10mA, 1V	100 @ 150mA, 2V	160 @ 100mA, 1V	250 @ 100mA, 1V	100 @ 150mA, 10V
Vce Saturation (Max) @ Ib, Ic	700mV @ 50mA, 500mA	400mV @ 5mA, 50mA	750mV @ 50mA, 500mA	700mV @ 50mA, 500mA	700mV @ 50mA, 500mA	1.6V @ 50mA, 500mA
Package / Case	TO-92-3	TO-92-3	TO-92-3	TO-92-3	TO-92-3	TO-92-3
Mounting Type	Through Hole	Through Hole	Through Hole	Through Hole	Through Hole	Through Hole
Operating Temperature (Max)	150°C	150°C	150°C	150°C	150°C	150°C
RoHS Status	ROHS3 Compliant	Not Specified	Not Specified	ROHS3 Compliant	ROHS3 Compliant	Not Specified

Engineering Selection Recommendations

Primary Substitutes (Full Parameter Compatibility):

BC32725BU and BC32740BU are the preferred substitutes for the BC327,412. Both devices are manufactured by onsemi with active product status, maintain the 45 V collector-emitter breakdown voltage specification, support 800 mA collector current (exceeding the 500 mA requirement), and are ROHS3 compliant. These parts provide direct functional replacement with enhanced current capability and identical thermal characteristics. BC32725BU features 160 minimum hFE at 100mA, 1V, while BC32740BU provides 250 minimum hFE at the same conditions, offering improved gain characteristics.

Secondary Substitutes (Reduced Voltage Rating):

2N4403BU is a Fairchild Semiconductor active product with 40 V collector-emitter breakdown voltage (5 V below the original specification) and 600 mA maximum collector current. This device is suitable for applications where the 45 V rating is not critical to circuit operation. The 750 mV saturation voltage at 50mA, 500mA matches the original specification.

PN2907BU is a Fairchild Semiconductor active product with 40 V collector-emitter breakdown voltage and 800 mA maximum collector current. This device exhibits 1.6V saturation voltage at 50mA, 500mA, which exceeds the original 700 mV specification and may impact switching performance in saturation-dependent circuits.

Not Recommended:

2N3906BU is limited to 200 mA maximum collector current, which is insufficient for applications requiring the full 500 mA capability of the BC327,412.

Frequently Asked Questions (FAQ)

Q: Can the 2N3906BU replace the BC327,412 in all applications?

A: No. The 2N3906BU is rated for 200 mA maximum collector current, while the BC327,412 is rated for 500 mA. This device is suitable only for applications requiring less than 200 mA collector current.

Q: What is the primary difference between BC32725BU and BC32740BU?

A: Both devices share identical electrical ratings: 45 V breakdown voltage, 800 mA collector current, 100 MHz transition frequency, and 625 mW power dissipation. The primary difference is DC current gain: BC32725BU provides 160 minimum hFE at 100mA, 1V, while BC32740BU provides 250 minimum hFE at the same conditions. Selection depends on circuit gain requirements.

Q: Why is the 45 V collector-emitter breakdown voltage important for substitution?

A: The 45 V rating establishes the maximum voltage the transistor can withstand between collector and emitter without breakdown. Substitutes with lower ratings (40 V) reduce the safety margin in circuits designed for 45 V operation. Substitutes must equal or exceed this specification for equivalent reliability.

Q: Are all substitute parts available in the same TO-92-3 package?

A: Yes. All identified substitute parts are packaged in TO-92-3 (TO-226AA) through-hole configuration, ensuring mechanical and pin compatibility with the original BC327,412 footprint.

Q: What does ROHS3 compliance indicate?

A: ROHS3 compliance indicates the device meets Restriction of Hazardous Substances Directive requirements, restricting lead, cadmium, mercury, and other hazardous materials. BC32725BU and BC32740BU are ROHS3 compliant, matching the original BC327,412 environmental specification.

Q: Can PN2907BU be used as a direct replacement despite the higher saturation voltage?

A: PN2907BU exhibits 1.6V saturation voltage at 50mA, 500mA, compared to 700 mV for the BC327,412. This higher saturation voltage increases voltage drop during saturation and may affect switching speed and power efficiency in saturation-dependent circuits. Compatibility depends on circuit tolerance for increased saturation voltage.

Q: Why is the BC327,412 classified as obsolete?

A: Obsolete status indicates the manufacturer has discontinued production. Active substitute parts ensure continued availability for circuit maintenance, repair, and new designs requiring equivalent functionality.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message