High Impedance VS Low Impedance Power supplies?

[danny davis]

What power supplies are High Impedance?

What power supplies are Low Impedance?


A High Impedance power supply creates a voltage drop, but what makes a power supply high impedance? or low impedance?

Batteries have impedance, how do you find out the batteries impedance?

 

[albert22]

Ideal voltage supplies by definition have zero internal impedance.
Ideal Current supplies by definition have infinite internal impedance.
The internal resistance of a battery can be calculated by measuring the voltage at no charge and the voltage drop when loaded with a suitable resistor. It only requires to apply the ohms law. Just consider the battery as an ideal voltage supply in series with a resistor. With no load the voltage drop in this "internal resistor" will be zero.
A regulated voltage power supply will try to keep a constant voltage with different loads (within practical limits) if you apply the method above you will calculate a very small "internal" resistance.
Similarly a constant current supply will vary the voltage to keep constant the current with different loads so the internal resistance will appear to be very high. You can think a constant current source as a high voltage ideal supply in series with a large resistor. Using load resistors that are much less than the "internal" resistor the current will will remain practically constant.

 

[danny davis]

which power supplys are low impedance?
which power supplys are high impedance?