Hey im not very good with the component side of things
im looking for an appropriate NPN transistor to switch on a 3.3v from vcc high side switching, to Neo 6m GPS module around 60mA by a mkr board from a digital pin 3.3v max 7mA
I know the max voltages should be careful about but unsure about the amount of current a digital pin can push out for the correct transitor?
tried using an ss8050 but no such luck voltage output wasn't enough
tia
Typically you would use a PNP transistor as a high-side switch. An NPN transistor would give you a voltage drop of about 0.6V, from 3.3V down to 2.7V or so. That's inherent in the way an NPN works, and has nothing to do with the specs of the transistor.
Almost any PNP would work, even the lowly 2N3906. The voltage drop should be no more than 0.1V.
ShermanP:
Typically you would use a PNP transistor as a high-side switch. An NPN transistor would give you a voltage drop of about 0.6V, from 3.3V down to 2.7V or so. That's inherent in the way an NPN works, and has nothing to do with the specs of the transistor.Almost any PNP would work, even the lowly 2N3906. The voltage drop should be no more than 0.1V.
makes sense cheers
When you pick a transistor look at the Vsat part of the specification. For example the 2N3906 has a Vsat of 0.25V at 10mA, as the current rises so does the Vsat value. Or you can simply use a P-Channel MOSFET and switch it, the voltage drop will be dependent on the RDSon at the current you are loading it with. This will also change depending on how well it is enhanced (turned on).This should not require any bias resistors or protection diodes. It always pays to read the data sheet.