Skip to main content
Electrical Engineering

Return to Answer

added 11 characters in body
Source Link
tobalt
tobalt
  • 23.4k
  • 26
  • 99

It's about their output impedance. These sources are pretty much the same thing, but we call low impedance sources "voltage sources" and we call high impedance ones "current sources".

Example

Take a 12 V car battery. ItBy itself, it is a reasonably good voltage source, because its internal series impedance is low for most purposes. Its output voltage would be always about 12 V, regardless of the load.

Now add a 1 MΩ resistor in series and suddenly it is a reasonably good current source, which will output a current of 1.2 µA through most loads. But it's output voltage would now be highly load dependent.

It's about their output impedance. These sources are pretty much the same thing, but we call low impedance sources "voltage sources" and we call high impedance ones "current sources".

Example

Take a 12 V car battery. It is a reasonably good voltage source, because its internal series impedance is low for most purposes. Its output voltage would be always about 12 V, regardless of the load.

Now add a 1 MΩ resistor in series and suddenly it is a reasonably good current source, which will output a current of 1.2 µA through most loads. But it's output voltage would now be highly load dependent.

It's about their output impedance. These sources are pretty much the same thing, but we call low impedance sources "voltage sources" and we call high impedance ones "current sources".

Example

Take a 12 V car battery. By itself, it is a reasonably good voltage source, because its internal series impedance is low for most purposes. Its output voltage would be always about 12 V, regardless of the load.

Now add a 1 MΩ resistor in series and suddenly it is a reasonably good current source, which will output a current of 1.2 µA through most loads. But it's output voltage would now be highly load dependent.

Source Link
tobalt
tobalt
  • 23.4k
  • 26
  • 99

It's about their output impedance. These sources are pretty much the same thing, but we call low impedance sources "voltage sources" and we call high impedance ones "current sources".

Example

Take a 12 V car battery. It is a reasonably good voltage source, because its internal series impedance is low for most purposes. Its output voltage would be always about 12 V, regardless of the load.

Now add a 1 MΩ resistor in series and suddenly it is a reasonably good current source, which will output a current of 1.2 µA through most loads. But it's output voltage would now be highly load dependent.