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mathman44
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Homework Statement
a) Design a current source using a simple DC power supply and a single large resistor. Assume
you want to supply loads which can vary between 1 k and 10 k and you want the current to stay within 5% of 1 mA.
b) Do the same thing using 2 DC power supplies and 1 NPN transistor with beta = 100 and
VBE = 0.6 V which will satisfy the same specifications. You are free to choose the values
of the power supply voltage and can use as many resistors as necessary.
The Attempt at a Solution
Just to make sure I'm understanding this correctly; if the load varies up to 10k ohms and we want the current to stay within 5% of 1 mA, then the load can only represent 5% of the total resistance, correct?
So the answer for (a) would be a 190k resistor connected to a 190V battery.
for b) I can put my load as a collector resistor, so the current it draws is independent of the load resistor value.
Am I going about this the right way?
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