S
Stretto
- Jan 1, 1970
- 0
http://tinypic.com/r/vy723d/7
I was just playing around and came up with a rather stupid CCR. As you can
see the base current modifies the slope = effective resistance. The IV
characteristics seem fairly constant. The resistances range from about 5k to
300k which easily can be changed by modifying the resistor values.
I'm sure the circuit can be simplified and optimized... anyone care to give
it a try? Seems like it might be possible to use some form of circuit
topology to get a nice VCR and/or CCR that works over a wide ranges of
voltages, currents, and resistances that an be floating.
I haven't found anything but JFETs for VCR's and they tend to have small
resistances(max I've seen is about 10k) and cannot be "floating"(at least
not without more complexity/cost).
I did find
http://alokgovil.com/Professional/Projects/Analog/Current-Controlled-Resistor/CCR-Document.pdf
for a CCR that supposedly has a wide functioning range of parameters but
seems a bit complex and costly. I'm looking something, not a digital pot,
that can replace a pot... or rather be controlled by a pot as I need a
single pot to control multiple sites.
Of course I have no clue if the circuit in I came up with actually works.
Just did some IV analysis on an idea and played around with it until I got
slopes that dependent on the base current. So please no flames...
I was just playing around and came up with a rather stupid CCR. As you can
see the base current modifies the slope = effective resistance. The IV
characteristics seem fairly constant. The resistances range from about 5k to
300k which easily can be changed by modifying the resistor values.
I'm sure the circuit can be simplified and optimized... anyone care to give
it a try? Seems like it might be possible to use some form of circuit
topology to get a nice VCR and/or CCR that works over a wide ranges of
voltages, currents, and resistances that an be floating.
I haven't found anything but JFETs for VCR's and they tend to have small
resistances(max I've seen is about 10k) and cannot be "floating"(at least
not without more complexity/cost).
I did find
http://alokgovil.com/Professional/Projects/Analog/Current-Controlled-Resistor/CCR-Document.pdf
for a CCR that supposedly has a wide functioning range of parameters but
seems a bit complex and costly. I'm looking something, not a digital pot,
that can replace a pot... or rather be controlled by a pot as I need a
single pot to control multiple sites.
Of course I have no clue if the circuit in I came up with actually works.
Just did some IV analysis on an idea and played around with it until I got
slopes that dependent on the base current. So please no flames...