O.K.
Now look at your cap values... 47uF is very large for this. Look at the ripple (ACrms) on C3. These caps really do not need to be so large. At least C1 & C2 could be made smaller. When you do this you may be able to return to EC80.
😉
Now look at your cap values... 47uF is very large for this. Look at the ripple (ACrms) on C3. These caps really do not need to be so large. At least C1 & C2 could be made smaller. When you do this you may be able to return to EC80.
😉
How much ripple on B+ is acceptable for a SE amplifier?
If I change R1 to 100 Ohm I get a B+ of 270V and a ripple of 4mV. Changing C1 and C1 to 10u I get a ripple of 103mV. But even with a reduced C1 and C2 I still get the warning messages for the EZ80. Attached is an image of where I am at, two current sinks to simulate independent RC filters per channel.
Adi
If I change R1 to 100 Ohm I get a B+ of 270V and a ripple of 4mV. Changing C1 and C1 to 10u I get a ripple of 103mV. But even with a reduced C1 and C2 I still get the warning messages for the EZ80. Attached is an image of where I am at, two current sinks to simulate independent RC filters per channel.
Adi
Attachments
ping "kevinkr" or "SY",
I think he can give you a good spec for ripple. Also you ripple will be more critical for the first stages of your amp (I think).
Leave R1 at 200 Ohms or you will have too much diode current...
It really looks like you need another RC section before your first current tap. Can you post or link to your amp schematic?
😉
I think he can give you a good spec for ripple. Also you ripple will be more critical for the first stages of your amp (I think).
Leave R1 at 200 Ohms or you will have too much diode current...
It really looks like you need another RC section before your first current tap. Can you post or link to your amp schematic?
😉
Try reducing the load current and see if you still get the warning.. 100mV ripple at the output stage is relatively low, but could be audible, with an SE amplifier like this I would aim for about 10mV - 20mV to assure that this noise is not audible at the speaker.
Kevin
Kevin
To get the EZ80 warnings to disappear I had to reduce the caps and increase the filter R. That really dropped my useable B+. Trying to make this work with the EZ80 is too much of a compromise. Everthing looks good with the EZ81 in there. With a slightly larger choke I am at <2mV ripple and well within the spec of the EZ81.
Got my power supply nailed down.
Thanks!
Adi
🙂
Got my power supply nailed down.
Thanks!
Adi
🙂
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