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dave cox · 29th Jul 2020, 1:34 pm

It's interesting to contrast the B12, previously posted by Peter, with this design with respect to how they define the output voltage.

The B12 defines a current, by applying a fixed voltage (145V) to a variable resistance (R20+R19+fraction of R18) and applies that current to a variable resistance (fraction of R18+R16+R21).

This design defines a fixed current by applying a fixed voltage to a fixed resistor (R3) then applies that current to variable resistance (R2+R8). This is simpler only because it does not worry about adjustments of zero (it can't do it) or span. If I were changing this to get to zero volts it would be quite similar!

dc

29th Jul 2020, 1:34 pm	#77
dave cox Nonode Join Date: Jan 2009 Location: Bristol, UK. Posts: 2,062	Re: High voltage regulator circuit. It's interesting to contrast the B12, previously posted by Peter, with this design with respect to how they define the output voltage. The B12 defines a current, by applying a fixed voltage (145V) to a variable resistance (R20+R19+fraction of R18) and applies that current to a variable resistance (fraction of R18+R16+R21). This design defines a fixed current by applying a fixed voltage to a fixed resistor (R3) then applies that current to variable resistance (R2+R8). This is simpler only because it does not worry about adjustments of zero (it can't do it) or span. If I were changing this to get to zero volts it would be quite similar! dc Attached Thumbnails