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why we use voltage supply

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Hi all,
I see all ic analog and digital use voltage source as supply not use current source. I don't know why, is there any benifit ?.
Anyone can give some ideas about this.
Thanks.
 

voltage supply can be easily aquired and current supply can be generate from voltage supply easily.
 

Actually , all power sources are voltage sources. There is nothing practical called current source. Current sources are used only during circuit analysis and modeling for simplifying.
 

tran said:
... all ic analog and digital use voltage source as supply not use current source.
Click to expand...
Not true!

For example, a current source is commonly used to measure resistance. In this case, a current source is connected to the resistance. The current source forces a constant current through the resistance, thus producing a voltage that is directly proportional to the resistance.
 

ahmedsalah00 said:
So where is the IC here?
Click to expand...
Some examples: 6N137, LM335.

Also, have a look at the **broken link removed** and IEEE 1451.4 (Class 1) for more about this.
 

I hope this theory 'll help to get clear from Voltage and current sources

Most sources of electrical energy (the mains, a battery, ...) are best modeled as voltage sources. Such sources provide constant voltage, which means that as long as the amount of current drawn from the source is within the source's capabilities, its output voltage stays constant. An ideal voltage source provides no energy when it is loaded by an open circuit (i.e. an infinite impedance), but approaches infinite energy and current when the load resistance approaches zero (a short circuit). Such a theoretical device would have a zero ohm output impedance in series with the source. A real-world voltage source has a very low, but non-zero output impedance: often much less than 1 ohm. Conversely, a current source provides a constant current, as long as the load connected to the source terminals has sufficiently low impedance. An ideal current source would provide no energy to a short circuit and approach infinite energy and voltage as the load resistance approaches infinity (an open circuit). An ideal current source has an infinite output impedance in parallel with the source. A real-world current source has a very high, but finite output impedance. In the case of transistor current sources, impedances of a few megohms (at DC) are typical. An ideal current source cannot be connected to an ideal open circuit. Nor an ideal voltage source to an ideal short circuit, since this would be equivalent to declaring that "5 is equal to 0". Since no ideal sources of either variety exist (all real-world examples have finite and non-zero source impedance), any current source can be considered as a voltage source with the same source impedance and vice versa. These concepts are dealt with by Norton and Thevenin's theorems.[/b][/b]
 

all ICs needs voltage sources to bias the transistors in the IC ,notice also that the current source itself needs a voltage bias.
 

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