- #1
StealthRay
- 51
- 0
Hi,
Anyone here can tell me how to control the saturation voltage of a pnp transistor?
I was actually doing a project and my design using a pnp transistor to energize a 5V relay.Since I am using 5V supply,I can't afford to drop too much voltage at VCE of the transistor.
The design was tested and it worked fine for the past 2 weeks.I was able to get 3.5V at the relay which was enough to energize the 5v relay.
Strangely,the circuit wasnt working yesterday and there was only 0.7V at the relay coil which the VCE of the transistor taking a large chunk of the voltages.
Anyone can advice what could be the reason the VCE suddenly so high?I increase the Ib to 6mA but still couldn't get the VCE down.
Or something wrong with the relay resulting the VCE so high?I tested the relay by directly applying power to it and it worked fine.
Or it could be the transistor itself was damaged and acted strangely.
Please advice.Thank you.
Anyone here can tell me how to control the saturation voltage of a pnp transistor?
I was actually doing a project and my design using a pnp transistor to energize a 5V relay.Since I am using 5V supply,I can't afford to drop too much voltage at VCE of the transistor.
The design was tested and it worked fine for the past 2 weeks.I was able to get 3.5V at the relay which was enough to energize the 5v relay.
Strangely,the circuit wasnt working yesterday and there was only 0.7V at the relay coil which the VCE of the transistor taking a large chunk of the voltages.
Anyone can advice what could be the reason the VCE suddenly so high?I increase the Ib to 6mA but still couldn't get the VCE down.
Or something wrong with the relay resulting the VCE so high?I tested the relay by directly applying power to it and it worked fine.
Or it could be the transistor itself was damaged and acted strangely.
Please advice.Thank you.