BC547 VS BC548 Transistor: What is the Difference ?
In this post we are going to discuss about BC547 VS BC548 transistor, you will find the difference between these two transistors such as pin differences, ratings, and characteristics comparisons. Additionally, we will also discuss the conditions in which you can use BC548 instead of BC547 and BC547 instead of BC548. BC547 and BC548 both are well known NPN transistors of the same BC54x series available in the TO-92 package. There are also many other transistors in this series such as BC546, BC549 and BC550. They are general purpose transistors means they are built to use in a variety of general purpose switching and amplification applications. In addition to that, they are also good quality and reliable transistors due to which they are used in commercial and industrial applications as well as in educational and hobby electronic projects.
BC547 VS BC548 Pin Difference
In the above pin comparison image we can see that the pin configuration of both the transistors are the same the first pin is “Collector”, second is “Base” and the third is “Emitter”. So they are pin-to-pin replacement to each other as regards the pin configuration.
Ratings & Characteristics Comparison:
| Ratings & Characteristics | BC547 | BC548 |
|---|---|---|
| Collector-Emitter Voltage (Vceo) | 50V | 30V |
| Collector Current (Ic) | 100mA | 100mA |
| Total Device Dissipation (PD) | 625mW | 625mW |
| DC Current Gain (hFE) | 110 To 800 | 110 To 800 |
| Frequency (fT) | 300 MHz | 300 MHz |
Can We Use BC547 Instead of BC548
As you can see in the above ratings and characteristics comparison chart the collector-to-emitter voltage of BC547 is 50V and BC548 is 30V, the collector current of both the transistors is 100mA, total device dissipation is 625mW, DC current gain is 110 to 800 and transition frequency is 300MHz. The ratings of both the transistors are the same except for the collector-to-emitter voltage but the BC547 has a higher collector-to-emitter voltage than BC548 so the BC547 transistor can be used instead of BC548 in almost any condition.
Can We Use BC548 Instead of BC547
In this situation, we will also look at the above ratings and characteristics comparison chart as we have already discussed all the other ratings of both the transistors are the same except the collector to emitter voltage and in this situation, there are some conditions in which we cannot use BC548 instead of BC547. Such as when it is used as a switch and the load(the things the transistor is driving) voltage is above 30V. So if the load requires more than 30V then you cannot use BC548 instead of BC547, in other conditions than that you will be having no problem using BC548 instead of BC547 in almost any type of circuit whether it is a switching or amplification circuit. But most of the time they are used in 12V and below 12V circuits or 24V and below 24V circuits so there will be no problem when you are using in these types of circuits.
Conclusion
BC547 and BC548 both are the transistor of same series and both are almost the same. The only difference is their collector-to-emitter voltage. The BC547 has a larger collector-to-emitter voltage than BC548 so BC547 can be used in place of BC548 in any situation and condition. But BC548 cannot be used instead of BC547 only in one condition when the load requires more than 30V. But if you are using them in circuits which are operating at 12V or under 12V or 24V or under 24V then this condition will not apply and you can use both of them interchangeably.
FAQs
Is BC547 and BC548 same?
Both the transistors are almost same the only difference is there collector to emitter voltage but if you are using them in circuits which are operating at 12V or under 12V or 24V or under 24V then there is not any problem whether you use BC547 instead of BC548 or BC548 instead of BC547.
What can I use instead of BC547?
There are several transistors that can be used instead of BC547 few of them are 2N3904, 2N4401 etc. Further details about that can be found on the BC547 page.
What is BC547 used for?
BC547 is a general purpose transistor and it can be used in electronic circuit to perform many general purpose switching, amplification, preamplification, oscillator tasks.
Which type of transistor is BC547?
BC547 is a small signal NPN general purpose BJT transistor designed to perform general purpose switching, amplification, preamplification, oscillator tasks in electronic circuits.
Why is BC547 popular?
BC547 is popular because it is a low cost and reliable general purpose small signal transistor that can be used in place of a variety of other transistors.
