Richardcavell
Member
Hi everyone,
I am comparing a BC558 PNP and a BC548 NPN transistor.
1. What I'm looking for is some kind of measure of how fast the transistor can switch on or off. On the datasheets, there is a 'gain bandwidth product' for each. Is this a standard way of measuring switching speed? Should I use it for that purpose?
2. Is there typically a difference in the Hfe (gain) for a PNP versus NPN type transistor?
3. The two differences between NPN and PNP are: The polarity is reversed, and NPNs are faster. Did I get that right? Is there any other important difference between the two types?
Richard the Newbie
I am comparing a BC558 PNP and a BC548 NPN transistor.
1. What I'm looking for is some kind of measure of how fast the transistor can switch on or off. On the datasheets, there is a 'gain bandwidth product' for each. Is this a standard way of measuring switching speed? Should I use it for that purpose?
2. Is there typically a difference in the Hfe (gain) for a PNP versus NPN type transistor?
3. The two differences between NPN and PNP are: The polarity is reversed, and NPNs are faster. Did I get that right? Is there any other important difference between the two types?
Richard the Newbie