Thanks man...
Yeah in a round-about way I thought I answered that..hehe
Yes, that could be done , but.
The reason we still need the original op-amp was for frequency compensation and current
regulation. This needs to be taylored to insure good performance.
This requires some feedback components to this op-amp to control spikes and overshoots
from the diodes current resistor for control of current as well.
Hence..The idea of adding another op-amp before this driver network...make sense?
Still, we could do this with the "new" circuit as the old one would need it anyway.
The fet is a different animal then say that bipolar transistor..as you well know
I just didnt go too far into detail.. just to keep the concept simple
You mentioned something that I've been noodling on for some time. Rather than modifying the internals of the PSU to support analog modulation directly, what would prevent you from mounting a power mosfet right at the output of the existing PSU and using that to give you analog modulation? (You could build a voltage divider to knock down the zero-to-five volts of the analog blanking signal to somthing more reasonable - say, zero to 1 volts - and then apply that to the gate of your mosfet.)
If we tried this...the boards diode driver will try to compensate for the lack of current and will try to make up for it..
I think that will cause problems... dunno..will have to try it.
Just lifting the diode and driver rail only might work.
But to really think about more ..it wont work...It wont be fast enough..
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