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Device which resistance increases with the current increase

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awan

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current sources

any device whose resistance increases with the increase in current
 

Al Farouk

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Re: current sources

the PTC (positive temperatue coefficient) it is a resistance that its value increase with temperature. and as power dissipation in resistance = I*I*R(I2*R) so as current increase temperature increase and so the resisatnce value
 

rudane

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Re: current sources

Even your basic piece of copper wire has a PTC (Positive temperature coefficient). As the current through the copper increases there are more free ions moving. These free ions impede the current flow and increase the resistance of the wire.
 

Fom

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Re: current sources

Any drain of MOS transistor with gate DC voltage>Vth has this feature.
 

kohtwe

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Re: current sources

any device whose resistance increases with the increase in current
because positive temperature coefficient
 

test_out

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current sources

What do you mean by resistance? You mean the input or output impedance?
 

Andrew8611

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Re: current sources

I think that any material with a PTC (Possitive temperature coeficient) like cooper, can change their resistance with the heat making it higher than normal.
 

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