Unterschiede

Hier werden die Unterschiede zwischen zwei Versionen angezeigt.

--- circuit_design:2_transistors [2023/03/28 08:55] – mexleadmin
+++ circuit_design:2_transistors [2023/11/30 01:11] (aktuell) – mexleadmin
@@ Zeile 1: / Zeile 1: @@
-====== 2. Diodes and Transistors ======
+====== 2 Diodes and Transistors ======
 <WRAP>
@@ Zeile 355: / Zeile 355: @@
 During electronics development, several integrated circuits (e.g. intelligent light sensor, microcontroller, intelligent LED) may require different voltage levels. This can lead to problems especially during data exchange if logic High has to be in a certain voltage range. This problem can be solved by a level converter.
-The level converter (also logic level converter, level shifter) enables the bidirectional connection of digital connections of different voltage levels, e.g. 5 V to 3.3 V.
+The level converter (also logic level converter, level shifter) enables the bidirectional connection of digital connections of different voltage levels, e.g. $5 ~\rm V$ to $3.3 ~\rm V$.
 <WRAP>{{url>https://www.falstad.com/circuit/circuitjs.html?running=false&ctz=CQAgjCAMB0l3BWK0wCYDMYBsGsBYM8B2SPATiJCIiQUgCgAzEdUkVVPFt1BLF1OGhIYkVPXRdGAdwAmAJwD2ABwA6ARxgAOSP0hDqaOGDJgieBJLDoApgFpK+wQ1nstWtx-Son7liBkFFQ1tXXppASc+SM8ocNjeflQ-ZI8GCNT2aI4uRLiMziz+MyTo9Ji89C1csviqmv48fCK4+RZqlvrwIj1weDh6NpyW4ZKoPv76ACV2QrHRvC59fTx9dGh0ceXhafauMa6wRa2QVZARLZ2C-Z7uG706tgOeQoYAGRBmnzT2SB+IRgAQwANgBnGwsDZxACy51ueXwUV66yIEiwHmGeUxRGccXQ6L2nQ6qBxW3osK+ZRaTh2AEkQGR+N59IzYttaPFWSZBHgPNz8qc+WQeV58QLeSwxaz0GLytKpUyfALWZkVaTymgMdF5rUIprfnzktT6B8JTLkbLxkCwRD1pt3udjubPmdnfoASDwZD7fEmrk-qdKQ8IghjplQ7l1fEI5L+DHmeL5XGnbLfVzhackwKY-zyMUMwx6fGlTHMuzzr6vgGEGgDeKg+da3kHQh4QHEXX3QFPRCRPQwAgyOAjd8XZ3fhN+pMB0OG-rmxOwFOp-3B43BHlW6Vekql8v4Kuh1u6zWNwGnO79weAB4gByCdAIPkmFhYCD7DwAEQAlvIbABjAAXb9FAAO1UUEACFv0AiCAAoAAkNAAeQAV0A5R0IASnoW9eS8NcsCIId8R5cAv1-ADgLAiDoNg0FEJQ9DMMAnDbwcJxvD6dhH1OciQDQjD0NomDcLvUkSUoOwkh0PiwA8WlQJYkTALEt8kEkz4tAgZIVn4xTlKg0Tb0HIcOA8IizMwOSPEEwy6PoAAjU4JQHCASHfF8GHY0MXOKPBNkWIcPxAaFv3-JR-zAwClGBYEbHkeCaNBO0ADU2NOSwXMoLA6EyvT5NC8LIui2L4sShjkoQWB0qc8ShwHd1zFOQqGCAA noborder}}
@@ Zeile 369: / Zeile 369: @@
 ==== 2.9.4 Voltage Doubler/Inverter ====
-As a power supply for electronics, $5 ~\rm V$ or $3.3 ~\rm V$ is often used. In the following chapter, we will see that a bipolar power supply is often used for operational amplifier circuits. To be able to generate $-5 ~\rm V$ at low currents from a $5 ~\rm V$ supply, [[https://en.wikipedia.org/wiki/Charge_pump|charge pumps]] are often used. One such can be seen in the simulation. In the oscilloscope (in the simulation below), the voltage $U_{\rm C1}$ is displayed at the input capacitor C1 and $U_{\rm C2}$ at the storage capacitor C1. This circuit can be found, for example, in IC [[https://www.renesas.com/eu/en/www/doc/datasheet/icl7660.pdf|ICL7660]] (Renesas), [[https://www.ti.com/lit/ds/symlink/lmc7660.pdf|LMC7660]] (TI), [[http://ww1.microchip.com/downloads/en/DeviceDoc/21465C.pdf|TC7660]] (Microchip) integrated. Details on how it works can be found in [[https://www.youtube.com/watch?v=LYKGuc6ibe0&ab_channel=tanzawalab|this video]], for example.
+As a power supply for electronics, $5 ~\rm V$ or $3.3 ~\rm V$ is often used. In the following chapter, we will see that a bipolar power supply is often used for operational amplifier circuits. To be able to generate $-5 ~\rm V$ at low currents from a $5 ~\rm V$ supply, [[https://en.wikipedia.org/wiki/Charge_pump|charge pumps]] are often used. One such can be seen in the simulation. In the oscilloscope (in the simulation below), the voltage $U_{\rm C1}$ is displayed at the input capacitor $C1$ and $U_{\rm C2}$ at the storage capacitor C1. This circuit can be found, for example, in IC [[https://www.renesas.com/eu/en/www/doc/datasheet/icl7660.pdf|ICL7660]] (Renesas), [[https://www.ti.com/lit/ds/symlink/lmc7660.pdf|LMC7660]] (TI), [[http://ww1.microchip.com/downloads/en/DeviceDoc/21465C.pdf|TC7660]] (Microchip) integrated. Details on how it works can be found in [[https://www.youtube.com/watch?v=LYKGuc6ibe0&ab_channel=tanzawalab|this video]], for example.
 <WRAP> {{url>https://www.falstad.com/circuit/circuitjs.html?running=false&ctz=CQAgjCAMB0l3EaQGwA4DsAmVBOT6MdIctMQBmHEMgVkhBoFMBaMMAKACUQAWMZcOgE9U9MEKiSe9ctHKT6MGuwDG4MGQ2p1ZTJG2LY8CJmhFMmNiNQ09ycpBpQjHbuXIDRFD720mQyJg8ODhmIeERVE6KzsoA7hRo1NK8-MmK7Alsuvo61EFQmXnZxdiFCR5+EnwC4gKQRZWCAk1a5YlVLUl6BkXYfhoUkDx5DQn9+SMOIxYjDWo0PCM4AosjYEsKRggMYWD6i+RC2GCoBi7sAOYMmxsja+DIMQ0ATiDowyAr7593knTwK4-dabD7rJ4KIolaESEpjZp5WajPoFJF1SbtdFowZIhoABwCuW+Tz8t0h1xJ4E2lP4zyKIno3we33hzNWeC+9SKNA5xKJXISlOJWE57WQIu+YNF8PwmhxZ2R4xFSImuMaSW+DOlXFSAiC9C1+oUvGeW2UACNqPYrSb6Nh5DLUajlQVHescSK4ewAB7UdBTYgUEgUQbrbQANwA9gAbAAuAENLowADoAZwAJpGAK7m6OMF7sAnomF6gqIQpF2GDLFlyG+ujyDROWy1MphkAAYUwPveEHE8hw62q4G0HY4vuQyCoGnQAQ5YAcvBHIE4ABkezxKIJ5DxAgj2wBVce8LeYI68PdGw-d2lDGYFJq46jgeCvwG36Z5VqDO0vt+vxofDADl3D1XIGmkeRbD8ARkBoTwYmAgB9MAkMgJDpBwVAkPQMw0DQ7ZUKI9g9FnUCQC8T8vBGDtVwAaUAhDvAEFkSMgMigJAoCIRo+j2EjCgnHLTC-EMctGyoMRJPYIA noborder}}
@@ Zeile 376: / Zeile 376: @@
 Study Questions:
-  * In which state is the voltage $U_{\rm C1}$ equal to $1 ~\rm V$? * In which state is the difference between the voltages $U_{\rm C2}-U_{\rm C1}$ across the two capacitors equal to $1 ~\rm V$?
+  * In which state is the voltage $U_{\rm C1}$ equal to $1 ~\rm V$?
+  * In which state is the difference between the voltages $U_{\rm C2}-U_{\rm C1}$ across the two capacitors equal to $1 ~\rm V$?
   * What happens if the voltage sources for $0 ~\rm V$ and $1 ~\rm V$ are reversed?
   * How can this circuit be implemented with diodes instead of changeover switches?
@@ Zeile 402: / Zeile 403: @@
 </WRAP>
-==== 2.9.7 Other MOSFET Applications====
+==== 2.9.7 MOSFET as Substitution for Diodes ====
+Diodes always show a voltage drop given by the forward voltage. To circumvent this issue a MOSFET can be used. \\
+The following example shows one way to cope with it, when two voltage sources should be combined (e.g. a rechargeable battery with $U_1$ and a nonrechargable buffer battery with $U_2$):
+  * The __left side__ depicts a way to combine the two voltages with diodes. The higher voltages will be led through the diode. The diode of the lower voltage is set in reverse, since the cathode of the diode is on the higher voltage \\ The disadvantages of this setup are:
+    * One cannot choose the voltage on the output. It will be always given by the highest voltage.
+    * There will always be the voltage drop of the diode
+  * The __right side__ shows an alternative way to connect both voltages: the antiparallel p-MOSFETs avoid conductivity via the due to the body diode. The MOSFET pair is driven by a BJT in order to have a digital signal as an input. \\ The disadvantages of this setup are:
+    * It is possible to short-circuit both voltages
+    * It is more complex
+Often the rightside one can be simplified and the disadvantages can be avoided by using integrated circuits (like [[https://www.analog.com/en/products/ltc4417.html|LTC4417]])
+<WRAP>{{url>https://www.falstad.com/circuit/circuitjs.html?ctz=CQAgzCAMB0l3AWAnC1b0DYQEYYCY48B2IsSADjwxSJAFZIdGEI6BTAWm2wCgAzcHhx5ygkAlFgI2aHSjQ8-EEizYRyrBPHYcs+YoDuYtaJXDRkHka1byzC1Zxrxo7BntRHbj3jwIXngBOIL7+WqE4CP6MuHA8AOYhfpH+EdhEWIyWwRzJ5KK5-iZQTHFGXGCaBWo+PAAuIBxa2FGNyS3ROPJ0GEShYETYSNhgQ0jyGHR0blQ92JTuzrEgACZsfACGAK4ANnUJbUXuhzgZJZZGYELFheZBjWYdjc2tMfCWADIPqq1c6k8xECbHYAZzY9E8Rm8AWhEQuOGOaWccJ4ACVnnZwOR-BxpkIwNjzuJGHIst00RjGGA6EJcc5qUIyQg3kSYHQeCtGnQzlpcepwqt1ts9hyuWcInzRBEhGtNrt9uUaVLkpKAvCIuF8mqeAAHEJazWuVoQLIHERG1Ja9KZTyJJpwFLPB3W866p0ee0xY2u8oIDBhArMjyWO1+oq-MOnG3ZZ7+gJNOMA0rw1W8yNaSwEWhNTEM55aPP+ACqvCzlKxOKikkJxcUZY4GGSvMmVXEIBLPHrjdSKpbSTC7brkGzIywEvmPYHRaHI8q8ZdNnbpeHJy1tzjxbUABoALYbAAenZXtyoOOSfmYS7wu4PPC+HDMV0Yf0kBCJwLBEJjD6wT4xgjJWIyjEMgz38UDbROKQsFuPNTQaHMAKgt9AQfaAWDoOxBl6XoaVIZRZGpLC3DIMBkDwdgOFcB1ZWFBVGlHfsGLfaUeByc841gyBOiAxxwjyRgUUufFuI0cBRMsARH1EswNR0GRSQUJQrnE8ChAiKRdEUmcQKQIQ4zAPS2xLa890Pes3HEFUbCbQcjxHX8jMQwyhE3RwVIQZIVJczxOS4TQvNc89BTlEU-MsnzvKMmUhXlHgACNnlknErnGXxGR4fcMSlBBswwkIGDbZIPgAew2FZMpCbgQmQEI4wo1yapAUryoSkJIAgKhwCIQTkhTbt43cURwkcBtz17CgmMMZiPEsjNRpqJjLJRRKG0gdScQYWgKOiNquGqrqhlc+byiGpjcXFPrRrO3luVbSwsrWy1n2QCBRkvZIAAUSoMNhAgAHX+gA7AAiAB5VEQf+kEAHENjqNhKofYaiCOMISCK-wAGUDAASzqABjAALDZ4p2Nhoe+36AZBABJIGdS2OoQR4AkcFEAAxHQyTfLgl1Z1xaC5oleZ0acBZCcZhbeGXnx0FqVmh1E2BBXGQTqErAglrBpfoWWQhAf7LCAA noborder}}
+</WRAP>
+==== 2.9.8 Other MOSFET Applications====
 MOSFETs are not only used for pure switching of currents. Further applications are also:
@@ Zeile 492: / Zeile 510: @@
     * Draw the simplified diode equivalent circuit of an NPN transistor and describe the working.
   * Explain the difference between a PNP and NPN transistor.
-    * Draw a circuit each with the respective switch connected to U+ = 5V and ground in such a way that switching through is possible with a voltage between U+ and ground at the base.
+    * Draw a circuit each with the respective switch connected to $U+ = 5~\rm V$ and ground in such a way that switching through is possible with a voltage between U+ and ground at the base.
     * Name the respective connections of the transistors in the drawing.
     * What voltage must be applied to the base in each case for the transistor to switch through?
@@ Zeile 526: / Zeile 544: @@
 The collector terminal is at the bottom.|
 It is a bipolar junction transistor.|
-To make I_C flow, the voltage U_BE must become positive.
+To make $I_\rm C$ flow, the voltage $U_{\rm BE}$ must become positive.
 </question>
 <question title="Which statement(s) about bipolar junction transistors is/are correct?" type="checkbox">
-The current I_C or the voltage U_BC controls the current flow I_B.|
+The current $I_\rm C$ or the voltage $U_{\rm BC}$ controls the current flow $I_\rm B$.|
 The input characteristic of a bipolar junction transistor corresponds to that of a diode.|
 The disadvantage of the bipolar junction transistor is the continuous current flow required in the conductive state.|