This isn't a homework problem, but I guess it is similar to one.
I'm looking at the circuit from http://www.electroboom.com/, the latest post. I also included the circuit in the pdf attached.
I want to know how this circuit works by calculating values in the circuit. This circuit is a power amplifier where Vin is an audio signal from a mp3 player. My work is found in the same attachment.
I'm not sure if I calculated the modes of operations correctly for the transistors but I think they look about right.
Besides the question if my work is correct, here are my other questions
1. How do I calculate the current going through the NPN_CE and PNP_EC
junction when they're not in cutoff?
2. How do I calculate the current or the power going into the speaker
assuming its something like an 8ohm speaker?
3. Is Vbe_on for transistors always 0.7V? I'm not sure how to read the
parameters on the datasheets. I didn't see 0.7V anywhere. I just assumed
it was 0.7V since the blog from http://www.electroboom.com/ said so. I'm
having a lot of trouble understanding datasheets.
I'm looking at the circuit from http://www.electroboom.com/, the latest post. I also included the circuit in the pdf attached.
I want to know how this circuit works by calculating values in the circuit. This circuit is a power amplifier where Vin is an audio signal from a mp3 player. My work is found in the same attachment.
I'm not sure if I calculated the modes of operations correctly for the transistors but I think they look about right.
Besides the question if my work is correct, here are my other questions
1. How do I calculate the current going through the NPN_CE and PNP_EC
junction when they're not in cutoff?
2. How do I calculate the current or the power going into the speaker
assuming its something like an 8ohm speaker?
3. Is Vbe_on for transistors always 0.7V? I'm not sure how to read the
parameters on the datasheets. I didn't see 0.7V anywhere. I just assumed
it was 0.7V since the blog from http://www.electroboom.com/ said so. I'm
having a lot of trouble understanding datasheets.
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