Contents
Which is the ideal current source for a resistive load?
Figure 1 shows the schematic symbol for an ideal current source driving a resistive load. There are two types. An independent current source (or sink) delivers a constant current. A dependent current source delivers a current which is proportional to some other voltage or current in the circuit.
How is an independent current source similar to an open circuit?
An independent current source with zero current is identical to an ideal open circuit. The voltage across an ideal current source is completely determined by the circuit it is connected to. When connected to a short circuit, there is zero voltage and thus zero power delivered. When connected to a load resistance,…
How is a current source different from a voltage source?
A current source is an electronic circuit that delivers or absorbs an electric current which is independent of the voltage across it. A current source is the dual of a voltage source.
Where does the current from a voltage follower come from?
The voltage follower is loaded by a constant (current sensing) resistor acting as a simple current-to-voltage converter connected in the feedback loop. The external load of this current source is connected somewhere in the path of the current supplying the current sensing resistor but out of the feedback loop.
How is an ideal current source similar to an open circuit?
An independent current source with zero current is identical to an ideal open circuit. The voltage across an ideal current source is completely determined by the circuit it is connected to. When connected to a short circuit, there is zero voltage and thus zero power delivered.
Why are ground currents important in a circuit?
This separation of the grounds helps to minimize or prevent noise from being generated within circuits due to ground currents. Such ground currents—think of them as changing currents—when applied to ground return paths, create voltage variations (recall Ohm’s Law) called noise.
How is a power supply connected to the Earth?
This power supply has a positive (+), a negative (-), and a GND (ground) terminal. As mentioned previously, the ground terminal (earth ground) is physically tied to the chassis, which in turn is connected to the ground wire within the power cord, which is finally connected to the earth via the three prong outlet.