- #1

bleh

thanks everyone

- Thread starter bleh
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- #1

bleh

thanks everyone

- #2

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Maybe stick an op-amp in it?

- #3

Dx

zener diodeOriginally posted by bleh

thanks everyone

- #4

eNtRopY

As a former analog IC designer, I recommend the following quick and dirty cure-all.

Put the current source in series with a resistor to ground. Take the voltage between these components and feed it into an inverting-configuration op-amp with unity gain. Follow this amplifier with a second inverting-configuration op-amp with unity gain. To modulate the attenuation of the current, change the value of the first resistor mentioned (the input resistor).

Here is your controlling equation.

Iout = (Rin / (Rin + R)) * In, where

R = value of matched resistors used in first inverting-configuration op-amp, and

Rin = input resistor.

eNtRopY

Put the current source in series with a resistor to ground. Take the voltage between these components and feed it into an inverting-configuration op-amp with unity gain. Follow this amplifier with a second inverting-configuration op-amp with unity gain. To modulate the attenuation of the current, change the value of the first resistor mentioned (the input resistor).

Here is your controlling equation.

Iout = (Rin / (Rin + R)) * In, where

R = value of matched resistors used in first inverting-configuration op-amp, and

Rin = input resistor.

eNtRopY

Last edited by a moderator:

- #5

Doc

- #6

bleh

its a battery for a lawn mower its 12 volts with 9.9 amps

- #7

Doc

- #8

eNtRopY

You should have mentioned this in the beginning. In this case, you don't need the fancy electronics I previously mentioned. You just need a current divider. You can make one by connecting your battery to two resistors connected in parallel. Ground the end of one resistor and feed the other end into your lawn mower. The same equation I previously gave you applies here. Just make sure that input resistance of your lawn mower is small compared to the resistance value of the resistors you use (< 10%).Originally posted by bleh

its a battery for a lawn mower its 12 volts with 9.9 amps

eNtRopY

- #9

bleh

im connecting the battery to something that runs on 12 volts dc and 500 milli amps and i dont want to break it because the battery has 9.9 amps so i want to reduce the amps, but the thing im hooking the battery up to can go up to 1 amp so i want to be abel to increase the amps when i need to by moving a dial or something

- #10

Doc

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