I am about to build an output stage for a sine generator.
I run across several circuits of AB class amplifiers but in spite of lot of reading I still have many basic doubts.
My questions:
1) A buffer output is expected to have gain by itself? In other words what defines the gain in a pushpull configuration?
2) Several function generators seem to set their output impedance just by using a series resistor of 50 / 75 / 600 ohms at the output. Is that all is needed?
3) Instead of building an AB stage, the LH0033 (or similar buffer), would be a better (if expensive) solution?
4) When reading about AB amps it seems that those specifically for audio and those used as an output stage of signal generators share different necessities. Besides the obvious low impedance loads in audio, is anything that make them so different?
5) Walter Jung in his IC Op-amp Cookbook says that the attached circuit has an output impedance of 10 Ohms. What determines that value? How could I change it, if possible?
6) Read somewhere in a forum that diodes as shown above are old use; that a Vbe multiplier should be used instead. Can anyone elaborate?
Gracias for any help to understand this a little more.
I run across several circuits of AB class amplifiers but in spite of lot of reading I still have many basic doubts.
My questions:
1) A buffer output is expected to have gain by itself? In other words what defines the gain in a pushpull configuration?
2) Several function generators seem to set their output impedance just by using a series resistor of 50 / 75 / 600 ohms at the output. Is that all is needed?
3) Instead of building an AB stage, the LH0033 (or similar buffer), would be a better (if expensive) solution?
4) When reading about AB amps it seems that those specifically for audio and those used as an output stage of signal generators share different necessities. Besides the obvious low impedance loads in audio, is anything that make them so different?
5) Walter Jung in his IC Op-amp Cookbook says that the attached circuit has an output impedance of 10 Ohms. What determines that value? How could I change it, if possible?
6) Read somewhere in a forum that diodes as shown above are old use; that a Vbe multiplier should be used instead. Can anyone elaborate?
Gracias for any help to understand this a little more.
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