Hi Folks:
I am studying an Emitter-Follower Amplifier using a TIP120.
There are two things that I can't understand.
1) The Base voltage in the simulation and the real world
turns out to be 10.23 volts. If you use the voltage divider
calculation, it should be 11.51 volts. If you disconnect the
base of the darlington from the voltage divider, the voltage
divider does show 11.51 volts.
2) The output signal in the real world is riding on a negative
dc level instead of 0 volts. The first thing I thought of was
to replace the output coupling capacitor but that made no
difference.
I am perplexed. Any help would be appreciated.
Thanks,
David
I am studying an Emitter-Follower Amplifier using a TIP120.
There are two things that I can't understand.
1) The Base voltage in the simulation and the real world
turns out to be 10.23 volts. If you use the voltage divider
calculation, it should be 11.51 volts. If you disconnect the
base of the darlington from the voltage divider, the voltage
divider does show 11.51 volts.
2) The output signal in the real world is riding on a negative
dc level instead of 0 volts. The first thing I thought of was
to replace the output coupling capacitor but that made no
difference.
I am perplexed. Any help would be appreciated.
Thanks,
David
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