Forward biased ideal diode=>no voltage drop?

In summary, an "ideal" diode in forward bias refers to a diode that has zero voltage drop when conducting in one direction. This is often used in high voltage designs where the 0.7 volt drop across the diode is insignificant compared to the much higher voltages in the circuit. However, an ideal diode would have a vertical forward conducting line on the "Y" axis, not to the right of it as shown in graphs. It conducts perfectly in one direction and blocks perfectly in reverse.
  • #1
pyroknife
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Forward biased "ideal" diode=>no voltage drop?

Does a forward biased ideal diode have no voltage drop?
 
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  • #2
Yes, although it is difficult to say how zero volts can be called forward bias.
 
  • #3
Of course, there is some voltage drop across a forward biased diode, but small. See the diode characteristics below.
Rectifier_vi_curve.GIF


When we speak abut an ideal diode, we either assume zero forward voltage or constant (0.7 V for Si diodes).
a13_clip_image002.JPG

ehild
 
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  • #4
The "ideal diode" is a convenient fiction which is used when the actual voltage across the diode doesn't matter enough to be included in a calculation.

This is often the case in high voltage designs where the 0.7 volt drop across the diode is trivial compared with the much higher voltages in the circuit.

A voltage of zero volts can't have a polarity.
 
  • #5
An ideal diode would have the vertical forward conducting line on the "Y" axis not to the right of it as these graphs show.
 
  • #6
vk6kro said:
Yes, although it is difficult to say how zero volts can be called forward bias.

Ideal diode has zero volts with non-zero forward current. "Forward biased" refers to direction of conduction current. An ideal diode conducts perfectly in 1 direction (no forward voltage drop). It blocks perfectly in reverse (no leakage current).

Ideal diode has zero volts with non-zero amps in forward direction, vice-versa in reverse.

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Claude
 

FAQ: Forward biased ideal diode=>no voltage drop?

1. What is a forward biased ideal diode?

An ideal diode is an electronic component that allows current to flow in one direction only. When the diode is forward biased, meaning the voltage at the anode is higher than the voltage at the cathode, it allows current to flow through it. This creates a low-resistance path for current to flow through in a circuit.

2. Why is there no voltage drop in a forward biased ideal diode?

In a forward biased ideal diode, there is no voltage drop because the diode is designed to have a very low resistance in the forward direction. This means that the voltage across the diode is nearly equal to the voltage of the power source, resulting in no significant voltage drop.

3. What are the benefits of using a forward biased ideal diode?

One of the main benefits of using a forward biased ideal diode is that it can act as a one-way valve for current, allowing it to flow in only one direction. This is useful for rectifying AC current into DC current, which is necessary for most electronic devices to function properly. Additionally, the low voltage drop of an ideal diode allows for more efficient use of power in a circuit.

4. Are there any limitations to using a forward biased ideal diode?

One limitation of using a forward biased ideal diode is that it cannot handle high currents or voltages. If the current or voltage exceeds the diode's maximum rating, it may fail or be damaged. Additionally, ideal diodes are not perfect and do have a small amount of resistance, which can affect the accuracy of voltage measurements in a circuit.

5. How is a forward biased ideal diode different from a regular diode?

An ideal diode has the same basic properties as a regular diode, but with a few key differences. Unlike a regular diode, an ideal diode has zero resistance in the forward direction and infinite resistance in the reverse direction. This means that it does not experience any voltage drop when forward biased, and does not allow current to flow in the reverse direction at all. Additionally, ideal diodes do not have any capacitance or inductance, making them more ideal for use in electronic circuits.

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