| Nächste Überarbeitung | Vorhergehende Überarbeitung |
| circuit_design:uebung_3.5.5 [2021/12/09 01:18] – angelegt tfischer | circuit_design:uebung_3.5.5 [2023/03/28 10:51] (aktuell) – mexleadmin |
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| <WRAP pagebreak></WRAP> | <WRAP pagebreak></WRAP> |
| <panel type="info" title="Exercise 3.5.5. linear "> <WRAP group><WRAP column 2%>{{fa>pencil?32}}</WRAP><WRAP column 92%> | <panel type="info" title="Exercise 3.5.5. Linear Voltage Regulator"> <WRAP group><WRAP column 2%>{{fa>pencil?32}}</WRAP><WRAP column 92%> |
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| In order to get a constant (lower) voltage from an higher voltage input or a source with a broader spread of the voltage (e.g. a battery) often linear regulators are used. | In order to get a constant (lower) voltage from a higher voltage input or a source with a broader spread of the voltage (e.g. a battery) often linear regulators are used. |
| One example could be to get $5V$ from the car battery voltage (between $11V...14V$) for a microcontroller in a control unit e.g. the brake control unit. | One example could be to get $5 ~\rm V$ from the car battery voltage (between $11 ~\rm V...14 ~\rm V$) for a microcontroller in a control unit e.g. the brake control unit. |
| Linear regulator here means that a transistor as a variable resistor is used to drop the unwanted voltage. | Linear regulator here means that a transistor as a variable resistor is used to drop the unwanted voltage. |
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| Below, two types of such a linear regulator are shown | Below, two types of such linear regulators are shown |
| - The first simuation shows a simple series regulator with a FET. "Series" here marks the fact that the transistor is in series to the load resistor $R_L$. The zener diode $D$ has a current limiting series resistors $R_D$ ahead. By the voltage divider of $R_D$ and $D$, a relatively constant voltage will be created. | - The first simulation shows a simple series regulator with a FET. "Series" here marks the fact that the transistor is in series to the load resistor $R_\rm L$. The Zener diode $D$ has a current limiting series resistors $R_\rm D$ ahead. By the voltage divider of $R_\rm D$ and $D$, a relatively constant voltage will be created. |
| - The second simulation shows a more sophisticated circuit. Here there is a feedback from the output of the transistor back to the transistor controlling voltage is given by $R1$, $R2$ and the operational amplifier. | - The second simulation shows a more sophisticated circuit. Here, there is feedback from the output of the transistor back to the transistor controlling voltage. This feedback is given by $R1$, $R2$, and the operational amplifier. |
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| <WRAP>{{url>https://www.falstad.com/circuit/circuitjs.html?running=false&ctz=CQAgjCAMB0l3BWcMBMcUHYMGZIA4UA2ATmIxAWwpABYqEBTAWjDAChtC8Rs1xiUPPmm6QobAE7gaNfoLAzwKUcngdZALwYA7BhKYZoRKFFjxIpS1eukTKaF0IJl2PFhCHj7ACbTZy7gVZMAEQQS1dfU9CNgBzPzC8QMVcWTFINgAlBLBlEDwxXJUxGjE+dNMENgB3HLzUpVEank5G2jBCNozObmdAvIQMTqKTDNqaDra+rskKPJHpzEFCtXjFjEFphvTmoLkhQtCMgDMD-d5CvNLwaCQYSBQ2AA8QMnAncAV37n9ZTOfPoEMEgwLhwBgfuBuAARAHETooRSsKiI8i-ECwgD2tBAhDS7TAZXS0AgZRx2DY2PIeJME0JYWJEAggnIFNcOLESD4ADVMQAbAAuAENYgwONxiCZ6YS4CBMgwAM4ASwVwu0AGMxUA noborder}} </WRAP> | Tasks |
| | * In both simulations there are two sliders on the right-hand side: \\ - //Input Voltage//, which changes the ingoing voltage between $5~\rm V...20~\rm V$ \\ - //Load Resistance//, which changes the load on the output between $10~\Omega...1~\rm k\Omega$ \\ Play with these sliders and look for the differences! What are these? |
| | * The lower simulation with the operational amplifier is also called "**L**ow **D**rop**O**out" (**LDO**). The dropout is the minimum voltage difference on the transistor. How can the terminology low dropoff can be explained? |
| | * To which primitive OpAmp circuit does the LDO circuit ($R_1$, $R_2$ and OpAmp) look similar to? \\ How can the controlling of the transistor input voltage $U_{\rm GS}$ be explained? |
| | * Given a load resistor of $R_\rm L=1~\rm k\Omega$, an input voltage $U_\rm I=20~\rm V$, and an output voltage $U_\rm O=5~\rm V$, what is the dissipated power on the load and on the transistor? |
| | * One LDO is the [[https://www.ti.com/lit/ds/symlink/tps746.pdf|TPS746]]. \\ - What is the Pin $\rm FB$ for? \\ - How does the [[https://www.ti.com/lit/ds/symlink/lm340.pdf|LM7805]] differ regarding the set-up in a circuit? |
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| <WRAP>{{url>https://www.falstad.com/circuit/circuitjs.html?running=false&ctz=CQAgjCAMB0l3BWcMBMcUHYMGZIA4UA2ATmIxAWwpABYqEBTAWjDAChtC8Rs1xiUPPmm6QobAOa0whECjzcaMnpBpRxAJ2mz5i5ShpixYeHDZalOw9vDz1J02wDuNg2JQG51yM7meRfmpu4i5gNGpgGLJgAuBRmuDhcdFJYHbGpj7YagBeDAB2DBpMKNCETNwQMJmktXX1pOqlXIQI8th4WDTEYB0UZeBsACaJQQqjyXIgeYXFzRWSE7oTuGpGbABKE2nceMbp6tZ8RlDQCL5hEXartqK+2Jy3NjvinNxtlXYI8S-rLpZPD5PHxaIEvIGYQQZMxSCEYQRAm7rACGgX4gl4xlixHASBYSAcpjkZ1Y8OIkF6GAQ5OID2JCFYe16lBoDMgrWQjlCsUiOk8vPEADMhFiMXwXtYwGdTpAUGwAB4UPBUNDkakqky0cDcAAyCoohEEMTVGBxaDEQTUG31PIQlUgOJkEEtIGtitYVBknwJGGd2pAABEbRAUNhyCZuMEXUHFazI3BaFS5JAqC63YmzZqaHhM6n-exY0nMLJs0hMDiIpH9aygoQS765CQtZ5rQB7ZAgQhraSa47QKpTTXYNjt3qd7tKTWamAQEPgKjDvrTzvJkAANVbABsAC7IiQMDiVJAZTliDYMADOAEsL7v8gBjA9AA noborder}} </WRAP> | <WRAP>{{url>https://www.falstad.com/circuit/circuitjs.html?running=false&ctz=CQAgjCAMB0l3BWcMBMcUHYMGZIA4UA2ATmIxAWwpABYqEBTAWjDAChtC8Rs1xiUPBILADwUEADUA+gHE2AJ3A0a-ESvApukZPA6qAXgwB2DBUwzQiEmPDikHjp6QkpoXQsLzY8WEJet2ABNlVS1uMA1RQUEjU3MAwjYAc1CQcLTcVR1INgAlNLAtEDwdIu0JGh0+HKhoBDYAd0LirM1tJp5OdtowQh7czm4vHoQMfvLxHRkAGU6aPtHiydylEcmRzEEyvVTNjEERtpzOyNVonj4L3IAzS7KxXjLiqvB6usgUNgAPEDJwTzgSIA7hhVR5H5AiIYJBgXDgDCg8DcAAikOI-RQUTh6Ro5DBIDRvwQhAgomGiPSkAgBIhxIIVOGYhQrFoyJAcwA9mzCNlemBqjloBBqmyqABJYwABwArgAXAA6AGdJJyADZygCGyQYbG55F5lVYgrqZPS-h4IAA8vLZYqVeqtTrlbMOEiAGIi6h8FggSV2l2O7W6nx-ECeiQC3Q6X0zTmaoLKvIMJUASyVWuMAGNdUA noborder}} </WRAP> |
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| You work in the company "HHN Mechatronics & Robotics" and are supposed to generate a bipolar signal ($-10V ... + 10V$) from a unipolar signal of a digital-to-analog converter ($0...5V$) in a project. A colleague recommended the circuit shown on the right. | <WRAP>{{url>https://www.falstad.com/circuit/circuitjs.html?running=false&ctz=CQAgjCAMB0l3BWcMBMcUHYMGZIA4UA2ATmIxAWwpABYqEBTAWjDAChtC8Rs1xiUPBILADwUEADUA+gHE2Ac1phCIFHm40VPSDQmQ2AJ2Wr1m7ShqQJYeHCMm1Vx2HU27BgO6PL1lJadrLzUAtG5-PV8oNm8wGj0wDFVRESTo4ziEtMzwN2tbOw49AC8GADsGQyYUaEImbggYD1IW1rbSCRquQmE8bDwsGmIwfrVa8DYAE3B4tQ0ZrNMQUoqqrvrFBbmG2dw9ILYAJS3Xbjx8vIlnPiCoaAQYk7c93O5g7E5XlzyOLgo3U4UbIAiQyAAyjy0yTcvS+BmMsMBsMwgny8E2yIwglhLwOAEMQgkxLx8mJiOAkCwkAU7GMEKwscRICMMAgmcQPnTWOcRpQaPTID1kIVYmJEqYAuLogAzHh8FJyi6afL3O6QFBsAAeFDwkVcFGIeqQCW4EO1CEIVDQ2POakgxqcIEOWtoBDtgiGgjQDrADRdNEIEAVNAwDWIDoCzu1NFtKNoTLUrNo4HC-rZakIHrSRAjeij4Di4AwQaIRb0JpAABEXRzwIGC-lCOXHfnayhPqw-NhyZE9NWAPbIEBNq6du13RpqIdUACSZQADgBXAAuAB0AM6SfsAG2XeIUDDYg5Gw-2ylsQ5gQanJ6oAHkV0u15ud3uDxvwRwGtYAGKT0zWCwIBzk+H6vvuh6jGASB-u4wqARAYL9nikwbocDDrgAluue5lAAxoeQA noborder}} </WRAP> |
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| - First, analyze what change is made by pressing the switch $S$. How does the output signal change? | |
| - Try to determine mathematically the relationship of $U_O$ and $U_I$ as $U_O(U_I)$ by superposition. | |
| - The circuit still has the problem that for an positive positive half-wave the output is still negative. Which additional circuit must be provided so that this problem can be solved? | |
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| </WRAP></WRAP></panel> | </WRAP></WRAP></panel> |
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