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No-current voltage regulator

So, it's not a low-current regulator which uses only a small current, instead this one is using no current at all (well, at least < 1 nA).
The regulator is especially suitable for low output currents.

Figure 1: circuit diagram of the no-current voltage regulator.

The regulator is very simple and uses a N-channel junction FET.
I used a FET type: BF256B
The output voltage is depending on the FET type used.
There can also be some spreading in output voltage for several FET's of the same type.
So test some FET's and pick out the one which gives the desired voltage.

 Input (Volt) Load = 100 Ω Load = 1 k.Ω Load = 10 k.Ω Load = 100 k.Ω Load = 1 M.Ω Load = 10 M.Ω 1 0.36 0.86 0.97 0.998 0.9998 1.0000 2 0.58 1.55 1.92 1.994 1.9994 1.9999 3 0.67 1.94 2.75 2.96 2.9988 2.9994 4 0.70 2.04 2.87 3.22 3.42 3.55 5 0.71 2.06 2.90 3.25 3.45 3.58 6 0.72 2.08 2.91 3.26 3.47 3.60 8 0.72 2.10 2.93 3.28 3.48 3.61 10 0.73 2.11 2.94 3.29 3.49 3.62 12 0.73 2.12 2.94 3.30 3.50 3.63

Table 1:  output voltage as function of input voltage and load resistor.

Figure 2: Output voltage for several load resistors.

We see the output voltage is depending on the load resistor.
But for load's higher then 100 kΩ the differences are small.
For such high load resistors, the minimum voltage drop across the regulator is very small.
The output voltage is almost not depending on temperature changes.
When using the BF256B the maximum input voltage is 30 Volt.

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