Verifying the Shockley Equation: Explaining a Circuit

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In summary, the Shockley Equation is a mathematical formula used to describe the relationship between current and voltage in a diode. It is named after William Shockley and is used to predict the behavior of diodes in electronic circuits. The equation has three main parameters: the saturation current, the ideality factor, and the thermal voltage. However, it is a simplified model and may not accurately predict the behavior of diodes in all situations. It can be verified through experimental measurements.
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retupmoc
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For my 3rd year lab i need to verify the Shockley equation by building the circuit shown on page 4 of the link below:

http://www.physics.gla.ac.uk/Physics3/Lab%20scripts/semiconductors.pdf [Broken]

Can anyone explain to me how this circuit works? thanks
 
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No one know, coz I've got to give a 5 min oral presentation describing how this circuit works before explaining my results and i really don't know where to start
 
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The Shockley equation, also known as the diode equation, is used to describe the current-voltage relationship in a semiconductor diode. It states that the current through a diode is proportional to the voltage across it, and is given by the equation: I = I0(e^(V/VT) - 1), where I0 is the reverse saturation current, V is the voltage across the diode, and VT is the thermal voltage.

To verify this equation, you will need to build the circuit shown on page 4 of the provided link. This circuit consists of a semiconductor diode, a variable resistor (potentiometer), and a voltage source. The diode is connected in series with the resistor and the voltage source.

When a voltage is applied across the diode, current will flow through the circuit. The amount of current depends on the voltage and the properties of the diode. As the voltage is increased, the current through the diode will also increase, following the Shockley equation.

To verify the equation, you will need to measure the current at different voltage levels and plot the results on a graph. The graph should show a non-linear relationship between current and voltage, with the current increasing exponentially as the voltage increases. This confirms the validity of the Shockley equation.

In summary, the circuit works by applying different voltages across the diode and measuring the resulting current, which is then used to verify the Shockley equation.
 

What is the Shockley Equation?

The Shockley Equation is a mathematical formula that describes the relationship between current and voltage in a diode. It is named after William Shockley, who discovered the equation while working at Bell Labs in the 1940s.

How does the Shockley Equation explain a circuit?

The Shockley Equation is used to predict the behavior of diodes in a circuit, specifically how the current changes with respect to the voltage. By understanding this relationship, engineers and scientists can design and analyze electronic circuits.

What are the parameters in the Shockley Equation?

The Shockley Equation has three main parameters: the saturation current, the ideality factor, and the thermal voltage. The saturation current is a measure of the number of charge carriers in the diode, the ideality factor accounts for deviations from ideal behavior, and the thermal voltage takes into account temperature effects.

How accurate is the Shockley Equation?

The Shockley Equation is a simplified model that assumes ideal diode behavior. While it provides a good approximation for most circuits, it may not accurately predict the behavior of diodes in more complex or non-ideal situations. Other factors, such as temperature and manufacturing variations, can also affect the accuracy of the equation.

How is the Shockley Equation verified?

The Shockley Equation can be verified through experimental measurements. By collecting data on the current and voltage of a diode at various operating conditions, the equation can be tested and compared to the theoretical predictions. If the data closely matches the equation, it can be considered verified for that specific diode.

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