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Added line breaks (2 x space at EOL) in the reference text, so it displays as intended (as per Markdown syntax)
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SamGibson ♦
SamGibson ♦
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common-source amplifier

ImI'm currently studying electronic devices. IveI've reached transistor amplifiers. The image above shows a common-source amplifier. ImI'm confused about why the textbook takes the load out for DC analysis. WontWon't the analysis be invalid after we connect the load back, wont conditions, eg, output voltage, change due to the re-connection of \$R_L\$? The textbook talks about how \$V_{BIAS}\$ vs \$V_{OUT}\$ is such that at about \$V_{DD}/2\$ the small-signal gain is the highest, using a plot that they present, which is fine, but how do I connect the open-circuit behaviour to the case where \$R_L\$ is actually there?

Edit: The image comes from page 475 of the following book,

title: "Microelectronics: An integrated approach", 
authors: "Roger T. Howe & Charles G. Sodini", 
publisher: "Prentice Hall", 
ISBN: "9780135885185"

common-source amplifier

Im currently studying electronic devices. Ive reached transistor amplifiers. The image above shows a common-source amplifier. Im confused about why the textbook takes the load out for DC analysis. Wont the analysis be invalid after we connect the load back, wont conditions, eg, output voltage, change due to the re-connection of \$R_L\$? The textbook talks about how \$V_{BIAS}\$ vs \$V_{OUT}\$ is such that at about \$V_{DD}/2\$ the small-signal gain is the highest, using a plot that they present, which is fine, but how do I connect the open-circuit behaviour to the case where \$R_L\$ is actually there?

Edit: The image comes from page 475 of the following book,

title: "Microelectronics: An integrated approach", authors: "Roger T. Howe & Charles G. Sodini", publisher: "Prentice Hall", ISBN: "9780135885185"

common-source amplifier

I'm currently studying electronic devices. I've reached transistor amplifiers. The image above shows a common-source amplifier. I'm confused about why the textbook takes the load out for DC analysis. Won't the analysis be invalid after we connect the load back, wont conditions, eg, output voltage, change due to the re-connection of \$R_L\$? The textbook talks about how \$V_{BIAS}\$ vs \$V_{OUT}\$ is such that at about \$V_{DD}/2\$ the small-signal gain is the highest, using a plot that they present, which is fine, but how do I connect the open-circuit behaviour to the case where \$R_L\$ is actually there?

Edit: The image comes from page 475 of the following book,

title: "Microelectronics: An integrated approach" 
authors: "Roger T. Howe & Charles G. Sodini" 
publisher: "Prentice Hall" 
ISBN: "9780135885185"

added 64 characters in body
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Yeslin Sequeira
Yeslin Sequeira
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common-source amplifier

Im currently studying electronic devices. Ive reached transistor amplifiers. The image above shows a common-source amplifier. Im confused about why the textbook takes the load out for DC analysis. Wont the analysis be invalid after we connect the load back, wont conditions, eg, output voltage, change due to the re-connection of \$R_L\$? The textbook talks about how \$V_{BIAS}\$ vs \$V_{OUT}\$ is such that at about \$V_{DD}/2\$ the small-signal gain is the highest, using a plot that they present, which is fine, but how do I connect the open-circuit behaviour to the case where \$R_L\$ is actually there?

Edit: The image comes from page 475 of the following book,

title: Microelectronics"Microelectronics: An integrated approachapproach", authors: Roger"Roger T. Howe & Charles G. SodiniSodini", publisher: Prentice Hall"Prentice Hall", ISBN: 9780135885185"9780135885185"

common-source amplifier

Im currently studying electronic devices. Ive reached transistor amplifiers. The image above shows a common-source amplifier. Im confused about why the textbook takes the load out for DC analysis. Wont the analysis be invalid after we connect the load back, wont conditions, eg, output voltage, change due to the re-connection of \$R_L\$? The textbook talks about how \$V_{BIAS}\$ vs \$V_{OUT}\$ is such that at about \$V_{DD}/2\$ the small-signal gain is the highest, using a plot that they present, which is fine, but how do I connect the open-circuit behaviour to the case where \$R_L\$ is actually there?

Edit: The image comes from page 475 of the following book,

title: Microelectronics: An integrated approach authors: Roger T. Howe & Charles G. Sodini publisher: Prentice Hall ISBN: 9780135885185

common-source amplifier

Im currently studying electronic devices. Ive reached transistor amplifiers. The image above shows a common-source amplifier. Im confused about why the textbook takes the load out for DC analysis. Wont the analysis be invalid after we connect the load back, wont conditions, eg, output voltage, change due to the re-connection of \$R_L\$? The textbook talks about how \$V_{BIAS}\$ vs \$V_{OUT}\$ is such that at about \$V_{DD}/2\$ the small-signal gain is the highest, using a plot that they present, which is fine, but how do I connect the open-circuit behaviour to the case where \$R_L\$ is actually there?

Edit: The image comes from page 475 of the following book,

title: "Microelectronics: An integrated approach", authors: "Roger T. Howe & Charles G. Sodini", publisher: "Prentice Hall", ISBN: "9780135885185"

added 64 characters in body
Source Link
Yeslin Sequeira
Yeslin Sequeira
  • 33
  • 5

common-source amplifier

Im currently studying electronic devices. Ive reached transistor amplifiers. The image above shows a common-source amplifier. Im confused about why the textbook takes the load out for DC analysis. Wont the analysis be invalid after we connect the load back, wont conditions, eg, output voltage, change due to the re-connection of \$R_L\$? The textbook talks about how \$V_{BIAS}\$ vs \$V_{OUT}\$ is such that at about \$V_{DD}/2\$ the small-signal gain is the highest, using a plot that they present, which is fine, but how do I connect the open-circuit behaviour to the case where \$R_L\$ is actually there?

Edit: The image comes from "Microelectronicspage 475 of the following book,

title: Microelectronics: An integrated approach" byapproach authors: Roger T. Howe & Charles G. Sodini, ISBN publisher: Prentice Hall ISBN: 9780135885185, page 475

common-source amplifier

Im currently studying electronic devices. Ive reached transistor amplifiers. The image above shows a common-source amplifier. Im confused about why the textbook takes the load out for DC analysis. Wont the analysis be invalid after we connect the load back, wont conditions, eg, output voltage, change due to the re-connection of \$R_L\$? The textbook talks about how \$V_{BIAS}\$ vs \$V_{OUT}\$ is such that at about \$V_{DD}/2\$ the small-signal gain is the highest, using a plot that they present, which is fine, but how do I connect the open-circuit behaviour to the case where \$R_L\$ is actually there?

Edit: The image comes from "Microelectronics: An integrated approach" by Roger T. Howe & Charles G. Sodini, ISBN: 9780135885185, page 475

common-source amplifier

Im currently studying electronic devices. Ive reached transistor amplifiers. The image above shows a common-source amplifier. Im confused about why the textbook takes the load out for DC analysis. Wont the analysis be invalid after we connect the load back, wont conditions, eg, output voltage, change due to the re-connection of \$R_L\$? The textbook talks about how \$V_{BIAS}\$ vs \$V_{OUT}\$ is such that at about \$V_{DD}/2\$ the small-signal gain is the highest, using a plot that they present, which is fine, but how do I connect the open-circuit behaviour to the case where \$R_L\$ is actually there?

Edit: The image comes from page 475 of the following book,

title: Microelectronics: An integrated approach authors: Roger T. Howe & Charles G. Sodini publisher: Prentice Hall ISBN: 9780135885185

added 141 characters in body
Source Link
Yeslin Sequeira
Yeslin Sequeira
  • 33
  • 5
Source Link
Yeslin Sequeira
Yeslin Sequeira
  • 33
  • 5