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--- electrical_engineering_and_electronics_2:block13 [2026/06/09 05:10] – mexleadmin
+++ electrical_engineering_and_electronics_2:block13 [2026/06/09 05:22] (current) – mexleadmin
@@ Line 1: / Line 1: @@
-TBD
-  - Semiconductor components \\ (approx. 4 blocks, based on previous lectures on [[circuit_design:2_diodes|Diodes]] and [[circuit_design:2_transistors|Transistors]] )
-    - Bipolar transistor (structure, designations, characteristic curve, characteristic values)
-    - Transistor as a switch (circuit, switching times and behavior)
-    - MOSFET (structure, comparison with bipolar transistor)
-    - Optional: Transistor as an amplifier
 <callout> A nice introduction to the bipolar transistor can be found in [[http://eng.libretexts.org/Bookshelves/Materials_Science/Supplemental_Modules_(Materials_Science)/Materials_and_Devices/Bipolar_Junction_Transistor|libretexts]]. Some of the following passages, videos and pictures are taken from this introduction. </callout>
@@ Line 562: / Line 551: @@
 ~~PAGEBREAK~~ ~~CLEARFIX~~
 ==== MOSFET output characteristics ====
-The drain current \(I_{\rm D}\) depends on
+The drain current $I_{\rm D}$ depends on
+  * the drain-source voltage $U_{\rm DS}$, and
+  * the gate-source voltage $U_{\rm GS}$.
-  * the drain-source voltage \(U_{\rm DS}\),
+{{url>https://www.falstad.com/circuit/circuitjs.html?running=false&ctz=CQAgjCAMB0lwTFa8CscCcAWOYDMA2feMedEfSEFETXKgUwFowwAoAM3E0xFwA4eYAOz5eA3ojDRqMSPFYAncCTGCVuAlHBxIrAObgRNXJKPc+W3WD4Rhok5Tu8UiR-AyVcTIUhy-IELIBrABuNBb8PJgRmpSI7kiBltKsAEqG9glO8HwWniB8juDJKKwA7sqIkVw81bph0caIjXUgzZSy1FJ5SKUVTrTNFoNQ5RlN49gdYyxVmi2xM0a4LuMEeazYdPBC8bvkkMP4PB0A+senkKeYYESnKEy3p2CPQpen8O+4rAAeBXQ3Sjoag3AHgCwAVV+IHQPkwWXgAMRNHBIAA4gBlaEkZq3Li4shRSiAZMJoShcD4cj58EJtuhKIJIQAdADOrPZbLZAEd2QAHMDAyCsgC2ADUyZgyKQeCghNRSHDUZiyXwyLhrOQhBATBBGSAmfz6UKWWKVREbprPNwURqDdY0CLxX8ULleBRLW6wbb+YVjabnTYxNQUOg6Pxhqioc70FVQ+RhLx0KI9QARLF-eFxIQM1BtWk2iwASWh8J4O0JmhyzVRWIARjRjm0Y1Q+NQCDJodUTADsLwLYJECyAIYAFwArgpRwBLAD2ADt2Uy5wp6HpZ3OSyhtUIyC4fPxqyoAMJjkesmfsdis1Kr9fYvj2OPuR-Jmgk6HENXoCDwa24LAFiAaYfnIYjxGAtStoBUYgMwZaYPuKDymgKK-iAc6MEeAAWQ5znO9AADasvQc44XOADG9DCiRZ4sgAsgA8hiABiACiAAqrBAA 700,500 noborder}}
-  * the gate-source voltage \(U_{\rm GS}\).
-{{url>https://www.falstad.com/circuit/circuitjs.html?running=false&ctz=CQAgjA7CAMB00OgJhE+0AcBWLBmAbAJxK5gYT5T5jghbR0CmAtGGAFADm4+DuSDMLxC4CMGOwBKPQQBZZM8EgzjcIDAzhq4KTbCzsAHuAhqkecNlRZ8IBWRAARI+CHX7uBuaj2VAcXYAJxEUJAgUNlDw8TBEdgB3RX5BYU8FaATFJFkUwWIJADcQkL4o3VQ7QVodJHwMYg0wrGJ8ZSwYfUz+EqSBCWNIBTTLW08fSxAAZUzI1GiwZTndFzAsBSQkGiFbDYV1hQKV2RpN+wtN8YdnAdwoAVswWVDoQjsJgEl2Mi3hR-tf-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-WnZi-knPZITsQhI2QWQc3jPMvXMOqwTTZgckjZNluRFhjhzPN6HDQtjDfKzQ3UdjXjNFwDIAkB8HaZgl3ZSQXEoawUG4m9iICED9lsE7skuiYXvvE7WDWEQIF01Y2Q+T8IBG2RRgwDTHlNCZrjobjmA2O7wSs8TjItGxXnMmgAN0xZ2S5IA  noborder}}
+\\
-A MOSFET has several operating regions. Their names can be confusing because they are not identical to the BJT names.
+<WRAP><imgcaption picP|Function of the MOSFET>
+{{elektronische_schaltungstechnik:mosfet-front-final-test_jpg_project-body.jpg?400}}
+</imgcaption></WRAP>
+A MOSFET has several operating regions. \\
+Their names can be confusing because they are not identical to the BJT names.
 <tabcaption tab_mosfet_regions|Basic regions of an n-channel enhancement MOSFET>
-^ Region ^ Approximate condition ^ Electrical behavior ^ Typical use ^
+^ Region                    ^ Approximate condition                       ^ Electrical behavior                          ^ Typical use     ^
-| cutoff | \(U_{\rm GS}<U_{\rm GS(th)}\) | no useful channel, \(I_{\rm D}\approx 0\) | open switch |
+| cutoff                    | \(U_{\rm GS}<U_{\rm GS(th)}\)               | no useful channel, \(I_{\rm D}\approx 0\)    | open switch     |
-| linear / ohmic region | \(U_{\rm GS}\) high, \(U_{\rm DS}\) small | behaves like a controlled resistor | closed switch |
+| linear / ohmic region     | \(U_{\rm GS}\) high, \(U_{\rm DS}\) small   | behaves like a controlled resistor           | closed switch   |
-| MOSFET saturation region | \(U_{\rm GS}\) high, \(U_{\rm DS}\) larger | current mainly controlled by \(U_{\rm GS}\) | analog operation, current-source-like behavior |
+| MOSFET saturation region  | \(U_{\rm GS}\) high, \(U_{\rm DS}\) larger  | current mainly controlled by \(U_{\rm GS}\)  | analog operation, current-source-like behavior  |
 </tabcaption>
+\\
 <callout type="warning" icon="true">
 The word **saturation** means different things for BJTs and MOSFETs.
@@ Line 595: / Line 589: @@
 \[
 \begin{align*}
-U_{\rm DS}\approx R_{\rm DS(on)}I_{\rm D}.
+U_{\rm DS}\approx R_{\rm DS(on)} \cdot I_{\rm D}.
 \end{align*}
 \]
@@ Line 606: / Line 600: @@
 P_{\rm on,MOS}
 =
-R_{\rm DS(on)}I_{\rm D}^2
+R_{\rm DS(on)} \cdot I_{\rm D}^2
 }
 \end{align*}
 \]
-<callout type="info" icon="true">
-**Unit check**
-\[
-\begin{align*}
-[P_{\rm on,MOS}]
-=
-\Omega\cdot{\rm A}^2
-=
-\frac{{\rm V}}{{\rm A}}\cdot{\rm A}^2
-=
-{\rm V\,A}
-=
-{\rm W}.
-\end{align*}
-</callout>
-<panel type="info" title="Simulation: MOSFET output characteristics">
-Things to try:
-  * change \(U_{\rm GS}\),
-  * observe the family of output curves,
-  * identify cutoff, linear/ohmic region, and MOSFET saturation region.
-{{url>https://www.falstad.com/circuit/circuitjs.html?running=false&ctz=CQAgjCAMB0lwTFa8CscCcAWOYDMA2feMedEfSEFETXKgUwFowwAoAM3E0xFwA4eYAOz5eA3ojDRqMSPFYAncCTGCVuAlHBxIrAObgRNXJKPc+W3WD4Rhok5Tu8UiR-AyVcTIUhy-IELIBrABuNBb8PJgRmpSI7kiBltKsAEqG9glO8HwWniB8juDJKKwA7sqIkVw81bph0caIjXUgzZSy1FJ5SKUVTrTNFoNQ5RlN49gdYyxVmi2xM0a4LuMEeazYdPBC8bvkkMP4PB0A+senkKeYYESnKEy3p2CPQpen8O+4rAAeBXQ3Sjoag3AHgCwAVV+IHQPkwWXgAMRNHBIAA4gBlaEkZq3Li4shRSiAZMJoShcD4cj58EJtuhKIJIQAdADOrPZbLZAEd2QAHMDAyCsgC2ADUyZgyKQeCghNRSHDUZiyXwyLhrOQhBATBBGSAmfz6UKWWKVREbprPNwURqDdY0CLxX8ULleBRLW6wbb+YVjabnTYxNQUOg6Pxhqioc70FVQ+RhLx0KI9QARLF-eFxIQM1BtWk2iwASWh8J4O0JmhyzVRWIARjRjm0Y1Q+NQCDJodUTADsLwLYJECyAIYAFwArgpRwBLAD2ADt2Uy5wp6HpZ3OSyhtUIyC4fPxqyoAMJjkesmfsdis1Kr9fYvj2OPuR-Jmgk6HENXoCDwa24LAFiAaYfnIYjxGAtStoBUYgMwZaYPuKDymgKK-iAc6MEeAAWQ5znO9AADasvQc44XOADG9DCiRZ4sgAsgA8hiABiACiAAqrBAA 700,500 noborder}}
-</panel>
 ==== MOSFET types ====
@@ Line 651: / Line 619: @@
 <tabcaption tab_mosfet_types|Basic MOSFET types>
-^ Channel type ^ Enhancement type / self-blocking ^ Depletion type / self-conducting ^
+^ Channel type  ^ Enhancement type / self-blocking  ^ Depletion type / self-conducting  ^
-| n-channel | off at \(U_{\rm GS}=0\), on for sufficiently positive \(U_{\rm GS}\) | on at \(U_{\rm GS}=0\), can be reduced by negative \(U_{\rm GS}\) |
+| n-channel  | off at \(U_{\rm GS}=0\), on for sufficiently positive \(U_{\rm GS}\)  | on at \(U_{\rm GS}=0\), can be reduced by negative \(U_{\rm GS}\)  |
-| p-channel | off at \(U_{\rm GS}=0\), on for sufficiently negative \(U_{\rm GS}\) | on at \(U_{\rm GS}=0\), can be reduced by positive \(U_{\rm GS}\) |
+| p-channel  | off at \(U_{\rm GS}=0\), on for sufficiently negative \(U_{\rm GS}\)  | on at \(U_{\rm GS}=0\), can be reduced by positive \(U_{\rm GS}\)  |
 </tabcaption>
+\\
 In many mechatronic power circuits, the most common device is the **n-channel enhancement MOSFET**.
@@ Line 662: / Line 630: @@
 <tabcaption tab_bjt_mosfet_comparison|BJT and MOSFET as switching elements>
-^ Property ^ BJT ^ MOSFET ^
+^ Property                    ^ BJT  ^ MOSFET  ^
-| control quantity | base current \(I_{\rm B}\) | gate-source voltage \(U_{\rm GS}\) |
+| control quantity            | base current \(I_{\rm B}\)                     | gate-source voltage \(U_{\rm GS}\)                                    |
-| stationary control current | required | approximately zero |
+| stationary control current  | required                                       | approximately zero                                                    |
-| stationary control loss | \(P_{\rm ctrl}\approx U_{\rm BE}I_{\rm B}\) | very small, but gate must be charged and discharged during switching |
+| stationary control loss     | \(P_{\rm ctrl}\approx U_{\rm BE}I_{\rm B}\)    | very small, but gate must be charged and discharged during switching  |
-| on-state loss | \(P_{\rm on}\approx U_{\rm CE,sat}I_{\rm C}\) | \(P_{\rm on}=R_{\rm DS(on)}I_{\rm D}^2\) |
+| on-state loss               | \(P_{\rm on}\approx U_{\rm CE,sat}I_{\rm C}\)  | \(P_{\rm on}=R_{\rm DS(on)}I_{\rm D}^2\)                              |
-| switching behavior | storage charge can slow turn-off | often faster, but gate capacitance matters |
+| switching behavior          | storage charge can slow turn-off               | often faster, but gate capacitance matters                            |
-| typical risk | current gain \(B\) varies strongly | gate oxide sensitive to overvoltage and ESD |
+| typical risk                | current gain \(B\) varies strongly             | gate oxide sensitive to overvoltage and ESD                           |
 </tabcaption>
 <callout type="warning" icon="true">
 MOSFET gates are sensitive.
-A too large \(|U_{\rm GS}|\) can destroy the thin gate oxide.
+A too large \(|U_{\rm GS}|\) can destroy the thin gate oxide. \\
 </callout>