Applications Diode.docx

***General Physics*** ***third lecture*** ***Applications Diode*** ***Dr.Ameen Alwan*** ***first stage*** ***Department of Bio Chemistry*** ***Al-Mustaqbal University*** ***2023- 2024*** (Applications Diode( **The PN dijunction** is obtained when combining the two types, negative and positi...

***General Physics*** ***third lecture*** ***Applications Diode*** ***Dr.Ameen Alwan*** ***first stage*** ***Department of Bio Chemistry*** ***Al-Mustaqbal University*** ***2023- 2024*** (Applications Diode( **The PN dijunction** is obtained when combining the two types, negative and positive from the semiconductor to each other. This combination is done by manufacturing the duo on one crystal of a semiconductor material so that one half becomes negative and the other positive by introducing the appropriate impurity material into the halves of the crystal. Depletion region When adding the two halves of the junction PN, and because the concentration of charge carriers electrons in the negative type and the gaps in the positive type is much greater than in the other type, i.e. there is a slope in the concentration of electrons dn / dx in the negative region as well as a slope in the concentration of gaps dp/ dx in the positive region, this will lead to the transfer or spread of some electrons to the positive region of the junction Arabs as well as the transfer of some gaps to the negative region.  Figure showing a junction (PN) The potential barrier It is known that the presence of two different charges separated from each other by a distance will create an electric field that in turn leads to the creation of an electric potential. As a result of the transition of charge carriers between the two halves of the junction, the number of electrons in the P region and the number of gaps in the N region increases, thus forming a potential difference between the two regions, an electric field generator opposite to the carriers, as this electric field leads to the generation of a voltage barrier, called the voltage generated in the state of equilibrium with the junction voltage. HGD junction for silicon = 0.7ev These diodes and crystalline diodes are important components in many electronic devices and circuits and have many uses in the field of electronics. Since you allow the current to pass in one direction and therefore the direction of the I-V properties is similar to them. وصلة الموجب والسالب - ويكيبيديا Dual junction idiomatic symbol in electrical circuits 1. **Benefits of crystal diode\*\*** 2. 1-Low power consumption (i.e. no energy is needed to heat wicks) 3. Small size and light weight.2 3- High mechanical durability 1-The wide difference between the constants of diodes of the same type. 2-You can\'t work with high capacity. 1. 3-Many of them are not suitable for operating at high frequencies. 4-Extreme dependence of the properties of these diodes on temperature **Power Supply** Most electronic devices and circuits need a continuous power supply. Which converts alternating voltage into continuous 1. rectification efficiency It is a measurement of the ability of the rate to maintain the value of the constant voltage to the change in the load resistance V~D.C\ non\ lod~- V~D.C\ lod~/ V~D.C\ lod~ =ɤ عامل التموج -Ripple factor 3 The rectifier converts alternating current or voltage into current or voltage in one direction 𝒓 = [\$\\sqrt{(\\ I\\text{rms}\\text{\\ I}\\text{D.C})2\\ - 1}\$]{.math.inline} Connection by forward bias method-1 The forward bias of the diode inducted the positive terminal of the battery to the P crystal and the negative terminal to the N crystal In this way we can reduce the barrier voltage and push electrons to pass through the displaced region to close the circuit and pass the current in it.  forward bias method Reverse Bias Connection The following attached figure shows the reverse bias of the diode, where the positive end of the battery is connected to the N crystal and the negative end to the P crystal. In this way, we can increase the barrier voltage and push the electrons to be attracted to the positive end of the battery and the gaps to be attracted to the negative end of the battery, which increases the barrier voltage and the displaced area and stops the flow of current in the circuit. Zener Diode Destructive collapse occurs at always high reverse potentials and is caused by the collision of fast electrons and the ejection of electrons from their outer orbit and the repetition of this process. Except when covalent bonds are ionized due to the very high electric field strength across the reverse biased junction, this phenomenon is called the Zenr effect in relation to the Zenr factor PN.