INA134 would be the opposite of what you need. That would be the DRV134.
They can both be used with a single supply, just like any other op-amp.
https://www.diyaudio.com/community/...-simmilar-to-drv134-but-single-supply.280835/
They can both be used with a single supply, just like any other op-amp.
https://www.diyaudio.com/community/...-simmilar-to-drv134-but-single-supply.280835/
Thank you very much for your answer.
But my whole system is a common environment., If I use drv135 in single power mode, my signal GND will be connected to the vee pin of drv135, which will cause serious problems
Simplest solution: connect the positive input to the output and the negative input to the ground of the source. Also connect the shield to the ground of the source, insert a physically small 100 nF capacitor in parallel with a 100 ohm resistor between the shield and the ground of the source if you get hum.
Simplest solution is balancing transformer. Just like i did for F1J. Its fully balanced amplifier, and many feed it with unbalaced signal by grounding one input.
My solution was small balacing transformer. Exactly the same one as dartzeel uses. Input signal is small, so this trafo is very small.
You can find link in F1J thread.
My solution was small balacing transformer. Exactly the same one as dartzeel uses. Input signal is small, so this trafo is very small.
You can find link in F1J thread.
Post #227 has a link
https://www.diyaudio.com/community/threads/firstwatt-f1j.169509/page-12#post-6599536
https://www.diyaudio.com/community/threads/firstwatt-f1j.169509/page-12#post-6599536
When I wrote post #4, I assumed a differential input with a reasonable common-mode signal handling and common-mode rejection. Please ignore post #4 if there is little or no common-mode rejection, like when you use two identical amplifiers driven in antiphase as a bridged amplifier.
Thank you for answering my question.
As you said, if you use the method you proposed before, my amplifier will make a lot of noise...
Sorry, I don't understand what the problem is.
How is the amplifier powered and how do you plan to power the single-ended to differential converter circuit?
That's odd, I would expect it either to work properly or to have a much reduced maximum power output, not to make a lot of noise.
Just tried and it didn't make any difference in the sim. THD and noise figures stayed exactly the same. Simplifies things by one less resistor though.
There must be something wrong with your noise simulation set-up then; a 40 nV/sqrt(Hz) noise source added to an 18 nV/sqrt(Hz) op-amp should be quite noticeable. Unfortunately I can't tell what is wrong from the screenshot. How do you define the output and input quantities for the noise analysis? Do resistors in your simulator produce thermal noise by default, like they do in SPICE and Spectre?
I'm using TINA-TI but don't have much experience with it. From what I can find, it does model Johnson noise by default. Noise analysis was 20Hz-20kHz with an S/N signal amplitude of 1.
EDIT: Ok, it was just something weird going on with the program. Now when I change R6 to 0 the noise figures lower by more than half.
EDIT: Ok, it was just something weird going on with the program. Now when I change R6 to 0 the noise figures lower by more than half.
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I found that a charge pump can be used to generate a simple negative power supply, so that differential audio drivers such as drv135 can be used~
What do you think
Hi, friend
I built the bread board according to your circuit diagram, but it didn't work (no sound). I don't know why.
A good first debugging step would be to measure the supply voltage and the DC voltages at the op-amp outputs; those should be around half the supply.