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Most people think of diode as a rectifier. Fair enough, it is because an ideal diode is taught to be a rectifier. In fact most people like the ideal diode characteristic; but dislike the non-ideal characteristics of diodes. However, some of the important inventions of our time are based on non-ideal characteristics of the diode. Below are a couple of samples:
1) Temperature sensor. A diode voltage changes with temperature. Assuming a fixed current going through the diode in the forward biased region, and the current is low enough that the diode resistance does not affect the voltage, the forward voltage has a negative temperature coefficient of about -2mv/degreeC. Once the temperature and voltage relationship is characterized with a fixed current, one can tell easily the temperature from the reading of the forward voltage.
2) Bandgap reference and regulator. This is related to temperature sensing as well. Since diode voltage has a negative temperature coefficient, a positive temperature coefficient voltage component added to the diode forward voltage would make an excellent stable voltage reference; a voltage that is independent of temperature. Turns out, the forward voltage is not only a function of temperature, it is also a function of current. To make life more interesting, the temperature coefficient of the voltage voltage is a function of current. In other words, if you have 2 identical diodes with different current through them, the difference in these two forward voltages also changes with temperature. this voltage is:
Vd1-Vd2 = (k*T/q) *ln( I1/I2)
where I1 and I2 are currents through the 2 identical diodes.
This voltage has a positive temperature coefficient and is directly propositional to T in degrees Kelvin. Utilizing this current, one can amplify and convert it into a voltage, adding this voltage to a diode voltage, you have the making of a bandgap reference.
As it turns out, this current is also great for temperature sensor applications.
What else can I help you with?
Is a diode laser a nd. yag laser?
No, a diode laser and an Nd:YAG laser are two different types of lasers. A diode laser uses a diode as the laser medium and is commonly used for various applications such as hair removal and skin treatments. On the other hand, an Nd:YAG laser uses neodymium-doped yttrium aluminum garnet as the laser medium and is often used for medical and cosmetic procedures, as well as in industrial applications.
What are some practical uses of diodes?
Diodes are largely used for changing AC into DC. A half wave diode bridge will use two diodes for this purpose. A full wave bridge uses four diodes to accomplish this task.See related links below.
What is unidirectional property of diode. Mention its uses?
the current flows in one direction only
Where is a diode used?
A diode is used as a rectifier, clipper and to get square wave form. The combination of diode (bridge) is used for full wave rectification. It also used as a voltage controlar. Different types of diodes have different uses in different appliences.
Is it possible to reduce the cut in voltage of a diode?
No,it is not possible to reduce or increase the cut in voltage of the diode after the manufacturing of the diode but we can design zener diodes of various values of cut in voltage.But it is able to do that only at the time of manufacturing
What is the full form of LED BULB?
An LED bulb simply means a Light Emitting Diode Bulb—a bulb that uses LED technology to produce light efficiently.
What are the functions and the uses of the diode?
A diode conducts in only one direction. Use this to rectify AC to absorb inductive kick from relay coils- protecting output transistors from inverse voltage. as simple logic elements OR, AND, etc.
How is zener diode different from a conventional diode or ideal diode?
zener diode :zener diode operates under reverse bias voltageideal diode :ideal diode operates under forward bias voltage
What is diode equation?
It is an equation that describes the I-V characteristic of a diode. In other words, how the current depends on the voltage.The Shockley diode equation uses an exponential expression. See the Wikipedia article on "Shockley diode equation" for more details. However, for many practical purposes, it's accurate enough to think of a diode as being "open" in the "forward" direction (no voltage drop), and having a voltage drop of about 0.7 V (in the case of diodes made from silicon) in the "reverse" direction.
What diode equation?
It is an equation that describes the I-V characteristic of a diode. In other words, how the current depends on the voltage.The Shockley diode equation uses an exponential expression. See the Wikipedia article on "Shockley diode equation" for more details. However, for many practical purposes, it's accurate enough to think of a diode as being "open" in the "forward" direction (no voltage drop), and having a voltage drop of about 0.7 V (in the case of diodes made from silicon) in the "reverse" direction.
Can a diode be used as rectifier diode?
yes, diode can be used as rectifier diode to convert ac to dc
What is impatt diode?
The read type diode are called impatt diode
