BD544A-S Equivalent & Substitute Parts Reference

Part Overview

The BD544A-S is a PNP bipolar junction transistor (BJT) manufactured by Bourns Inc. It features a collector-emitter voltage of 60V, a maximum collector current of 8A, and a maximum power dissipation of 2W in a TO-220-3 through-hole package. This part is currently classified as Obsolete. As a result, it is necessary to identify and evaluate substitute or equivalent bipolar (BJT) transistors to ensure continued product support and repair capability within compatible designs.

Key Parameters

Parameter	Value
Transistor Type	PNP
Voltage - Collector Emitter Breakdown (Max)	60 V
Current - Collector (Ic) (Max)	8 A
Vce Saturation (Max) @ Ib, Ic	1V @ 1.6A, 8A
Current - Collector Cutoff (Max)	700µA
DC Current Gain (hFE) (Min) @ Ic, Vce	15 @ 5A, 4V
Power - Max	2 W
Operating Temperature	-65°C ~ 150°C (TJ)
Package / Case	TO-220-3
Mounting Type	Through Hole
RoHS Status	ROHS3 Compliant

Substitute Part Grouping Explanation

Substitution is determined strictly through comparison of essential electrical and mechanical parameters. These key substitution criteria for a bipolar (BJT) transistor in this category are:

Transistor Type: PNP
Collector-Emitter Breakdown Voltage (Vce)
Maximum Collector Current (Ic)
Power Dissipation (W)
DC Current Gain (hFE) at specified current and voltage
Saturation Voltage (Vce(sat)) at a specified base and collector current
Case/Package (TO-220-3, Through Hole)
Only parts matching or exceeding these specified parameters are considered as eligible substitutes.

Parameter Comparison

Manufacturer Part Number	Manufacturer	Transistor Type	Vce (Max)	Ic (Max)	Vce(sat) (Max) @ Ib, Ic	Current - Collector Cutoff (Max)	DC Current Gain (hFE) (Min) @ Ic, Vce	Power - Max	Operating Temperature	Package / Case	Mounting Type	RoHS Status	Product Status
BD544A-S	Bourns Inc.	PNP	60 V	8 A	1V @ 1.6A, 8A	700µA	15 @ 5A, 4V	2 W	-65°C ~ 150°C (TJ)	TO-220-3	Through Hole	ROHS3 Compliant	Obsolete
2N6109 PBFREE	Central Semiconductor Corp	PNP	50 V	7 A	3.5V @ 3A, 7A	1mA	30 @ 2.5A, 4V	40 W	-65°C ~ 150°C (TJ)	TO-220-3	Through Hole	ROHS3 Compliant	Obsolete
2N6490G	onsemi	PNP	60 V	15 A	3.5V @ 5A, 15A	1mA	20 @ 5A, 4V	1.8 W	-65°C ~ 150°C (TJ)	TO-220-3	Through Hole	ROHS3 Compliant	Obsolete
MJE2955T	NTE Electronics, Inc	PNP	60 V	10 A	8V @ 3.3A, 10A	700µA	20 @ 4A, 4V	75 W	-55°C ~ 150°C (TJ)	TO-220-3	Through Hole	RoHS non-compliant	Active
MJE2955TG	onsemi	PNP	60 V	10 A	8V @ 3.3A, 10A	700µA	20 @ 4A, 4V	75 W	-55°C ~ 150°C (TJ)	TO-220-3	Through Hole	ROHS3 Compliant	Active
TIP32AG	onsemi	PNP	60 V	3 A	1.2V @ 375mA, 3A	300µA	10 @ 3A, 4V	2 W	-65°C ~ 150°C (TJ)	TO-220-3	Through Hole	ROHS3 Compliant	Active
TIP42A	NTE Electronics, Inc	PNP	60 V	6 A	1.5V @ 600mA, 6A	700µA	15 @ 3A, 4V	2 W	150°C (TJ)	TO-220-3	Through Hole	RoHS non-compliant	Active
TIP42A-BP	Micro Commercial Co	PNP	60 V	6 A	1.5V @ 600mA, 6A	700µA	30 @ 300mA, 4V	2 W	-65°C ~ 150°C (TJ)	TO-220-3	Through Hole	Not specified	Active
TIP42AG	onsemi	PNP	60 V	6 A	1.5V @ 600mA, 6A	700µA	15 @ 3A, 4V	2 W	-65°C ~ 150°C (TJ)	TO-220-3	Through Hole	ROHS3 Compliant	Active

Engineering Selection Recommendations

BD544A-S is designated as Obsolete. Substitute parts with an Active status, ROHS3 Compliant classification, and matching mechanical and electrical characteristics provided above can be selected for direct replacement, subject to compliance requirements and inventory availability.

Frequently Asked Questions (FAQ)

Q1: What electrical parameters are critical when selecting an equivalent transistor for BD544A-S?
A1: Critical parameters include transistor type (PNP), collector-emitter breakdown voltage (Vce), maximum collector current (Ic), power dissipation, DC current gain (hFE) at specified current and voltage, and collector-emitter saturation voltage (Vce(sat)) at a given base and collector current.

Q2: Why is the package type and mounting important for substitution?
A2: Mechanical compatibility ensures that the substitute fits the existing PCB footprint and can operate with the same cooling and mounting infrastructure. All substitutes here use the TO-220-3 through-hole package.

Q3: Are the listed substitute transistors direct replacements for the BD544A-S?
A3: Listed substitutes match the BD544A-S in transistor type, package, and the majority of key electrical parameters, based strictly on the input data. Selection should be aligned with these specified characteristics.

Q4: How do RoHS and product status affect selection?
A4: For applications requiring compliance with hazardous substance regulations, only RoHS-compliant and Active substitutes from the list should be used. Product status indicates ongoing manufacturer support.

Q5: Is matching DC current gain (hFE) always required?
A5: Substitution requires hFE to meet or exceed the minimum specified for the main part at the stated test conditions, as per the provided data.

Q6: Can substitutes be used interchangeably in all applications?
A6: Only if all explicitly listed parameters (electrical and mechanical) strictly match those required for the application, as given in the provided tables. No assumptions beyond the provided parameters are to be made.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message