Timeline for Anyone have a Falstad simulation of a two transistor common-emitter amplifier? [closed]
Current License: CC BY-SA 4.0
19 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jan 22 at 20:28 | comment | added | user84299 | Yes thank periblesis, I think I’m good, I believe I understand what’s going on though it took a bit of digging. | |
| Jan 22 at 17:42 | comment | added | periblepsis | @rhody It's a bad design, in isolation, because of how much its gain depends upon the input signal, as I show. But it is somewhat also dependent on the operating temperature, as well. In general, the circuit is fine if and only if the gain itself isn't important (which may be at times -- class-C perhaps) or where there is global NFB involved in the larger circuit context. Are you good at this time, then? | |
| Jan 22 at 17:07 | comment | added | user84299 | @greybeard I think that’s what I’ll have to do, I was hoping someone might have one already. However after sleeping on it I believe I now understand, I misunderstood the role coupling capacitor which turned out to be the key to my question. | |
| Jan 22 at 16:57 | comment | added | user84299 | @periblepsis didn’t realize it was a bad design, this configuration is in all the textbooks I have and many internet sites discuss it. However my main interest in understanding how the coupling works, but I think I’ve since figure it out now. I had a misunderstanding of the interaction between the capacitor and the base biasing. | |
| Jan 22 at 16:52 | comment | added | user84299 | @G36 thanks for the links, I have a simulation for a single stage but don’t have one for two stages, your second link is useful however. | |
| Jan 22 at 16:51 | comment | added | user84299 | Looks like I asked a bad question plus it’s not that clear. I think it’s ok to delete it, plus I’ve since managed to understand what’s going on. I misunderstand what the coupling capacitors did. | |
| Jan 22 at 16:24 | history | closed |
Andy aka Voltage Spike♦ |
Needs details or clarity | |
| Jan 22 at 15:18 | comment | added | SamGibson♦ | @rhody - Hi, To comply with the site rule on referencing, please edit your question & add the PDF / video / webpage name & link to the source of that schematic. TY | |
| Jan 22 at 15:16 | comment | added | G36 | Here you have a Falstad sim of a CE amplifier tinyurl.com/yue25lho And another one tinyurl.com/ylmfd5jz | |
| Jan 22 at 10:10 | review | Close votes | |||
| Jan 22 at 16:24 | |||||
| Jan 22 at 9:54 | comment | added | periblepsis | @rhody Read here where I discussed the stage, recently, in detail. You may wish to study this example, which is similar enough but includes the extremely useful global NFB that makes it a good circuit to study. I'm not interested in belaboring a poor stage pairing as you show. If you are stuck on it, have at it. But I would be interested in providing a useful discussion of this latter example if that would help. | |
| Jan 22 at 9:07 | history | edited | ocrdu | CC BY-SA 4.0 |
added 3 characters in body; edited tags; edited title
|
| Jan 22 at 8:46 | answer | added | Antonio51 | timeline score: 1 | |
| Jan 22 at 8:04 | comment | added | greybeard | Start with Falstad's demonstration CE amp. Duplicate and connect input of the second stage to output of the first. Find out why the amplification of the first stage no longer is almost 10. | |
| Jan 22 at 7:20 | comment | added | periblepsis | @rhody That design cannot be made to work well. The output signal will be grossly distorted. Period. You should study something that may work, rather than not work. Either include local NFB via emitter degeneration in both stages or else include global NFB to both or find another topology. | |
| Jan 22 at 6:55 | history | edited | user84299 | CC BY-SA 4.0 |
added 184 characters in body
|
| Jan 22 at 6:49 | comment | added | user84299 | I just came across this video which helped at lot, but a simple capacitor coupled circuit is what I’m looking for (will update question): youtube.com/watch?v=3CVcyyJyWu4 | |
| Jan 22 at 6:10 | comment | added | Math Keeps Me Busy | There are many two transistor amplifier topologies. Do you want one with both transistors configured as common emitter amplifiers? A very common two transistor topology is a differential pair, which takes two inputs and amplifies their difference. | |
| Jan 22 at 5:33 | history | asked | user84299 | CC BY-SA 4.0 |