Sidenote: Just based on listening, this board like many similar power supplies may not like low esr caps. Especially the 470uf at the output. Nichicon FG sounds good there.
Oh, I forgot those.where is the red led near the right opamp?
Seems to be good now, after adjusting the potentiometer to 1K/9K.
The output is still "wavy" or is this how it supposed to look?
Thanky you btw!
Oh, I forgot those.
Seems to be good now, after adjusting the potentiometer to 1K/9K.
The output is still "wavy" or is this how it supposed to look?
Thanky you btw!
View attachment 1308360
Its supposed to be a straight line. perhaps this is oscillation?
Its supposed to be a straight line. perhaps this is oscillation?
I have no idea, but I couldn't fix it, so I remade the whole thing from the schematic in #343.
The output is still bad tho.
What I've noticed is that modifying the potmeter values does nothing to the output, but I cannot see any wiring mistakes.
+If I lower the value of the 10KuF filter cap, the sawtooth becomes steeper, but increasing doesn't fix the issue.
Attachments
Tried 28V, 24V, 9V and 8V, but it doesn't change the output.what is the input voltage? your regulator may be dropping out.
It may be just a simulation error.
I finally got it working in Multisim13, but I can only set the output between ~22V-4V (With the 50K and 10K pots)
I should use a bigger transformer for the input to get 24volts?
I should use a bigger transformer for the input to get 24volts?
I started the board for the first time today with 12V output and 15V AC input, and as I expected MJE15030 get very hot (70-80 degrees open air) with 3.5cm radiator (as on aliexpress boards) with low load. Should I decrease input voltage or better to change radiator to bigger one ?
Buy 12vac trafo. The power lost in warmth depends also on the current flowing through the bjt. P =(( 12*1.44)-12)*I
Semms abnormal, something if wrong. What is the resistance value ? Have you bought it assembled ot just a board ?MJE15030 get very hot (70-80 degrees open air) with 3.5cm radiator (as on aliexpress boards)
I've changed transformator to 12V AC and all is well, the temp of bjt decrease as minimum twicely or more. 21V in is too much voltage dropSemms abnormal, something if wrong
The TI documentation states that TLE2072 is direct upgrade to TL07x and also now this op amp has a direct drop-in replacement.OPA2992, have you replaced TL, what reason ?
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That's right but you are posting something about OPA2992 ?? Just a mistake or ??The TI documentation states that TLE2072 is direct upgrade to TL07x and also now this op amp has a direct drop-in replacement.
Now is clear, thanksNo, OPA2992 is a newer and better version of TLE2072 according to manufacture
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