Hi All,
**broken link removed**
I've probably made a really silly mistake somewhere but I'm trying to work out an expression for the self biasing of this transistor circuit above so that the output always sits half way between the supply rail. I applied KCL to the node and got an expression above. I put the values in the expression which yielded a value for me to use. To test the expression I set up the circuit underneath with Vs = 9v and a 2n222 (Hfe = 200). However the simulation shows the values do not quite give an output which is half way below the rail. So to investigate further I worked out the base and collector currents in the circuit being simulated and see that Ic does not equal Hfe(Ib). Ic seems to be higher than it should be. Just wondering if I've missed something glaringly obvious? What's gone wrong!
Thanks,
Megamox
**broken link removed**
I've probably made a really silly mistake somewhere but I'm trying to work out an expression for the self biasing of this transistor circuit above so that the output always sits half way between the supply rail. I applied KCL to the node and got an expression above. I put the values in the expression which yielded a value for me to use. To test the expression I set up the circuit underneath with Vs = 9v and a 2n222 (Hfe = 200). However the simulation shows the values do not quite give an output which is half way below the rail. So to investigate further I worked out the base and collector currents in the circuit being simulated and see that Ic does not equal Hfe(Ib). Ic seems to be higher than it should be. Just wondering if I've missed something glaringly obvious? What's gone wrong!
Thanks,
Megamox