I'm designing a TPA6120 based headphone amp, is there anyone can give me some advice

shadownee

Member
2012-02-13 6:08 am
I'm designing a high-fadely headphone amplifier based on TPA6120, is there anyone can give me some advice?

Here is the schematic I designed.:D
 

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jcx

Member
2003-02-17 7:38 pm
..
you might look at Peranders TPA6120 project for ideas, pwr pad soldering hints

rather than a independent buffer op amp in front I much prefer a Multiloop topology where a good quality "audio" op amp applies global feedback around the TPA6120 - this improves the performance of both amps in the composite

Walt Jung has written about these multiloop composite amps for audio line driving, check his site, his "Op Amp Applications" book (online at Analog.com)
 

shadownee

Member
2012-02-13 6:08 am
you might look at Peranders TPA6120 project for ideas, pwr pad soldering hints

rather than a independent buffer op amp in front I much prefer a Multiloop topology where a good quality "audio" op amp applies global feedback around the TPA6120 - this improves the performance of both amps in the composite

Walt Jung has written about these multiloop composite amps for audio line driving, check his site, his "Op Amp Applications" book (online at Analog.com)

Thanks for your advice.
I'm interesting of Peranders TPA6120 project.
Could you please provide me some information about it?
 
The TPA6120 has high input bias...you might consider an input buffer.
Don't forget to design your board to use the thermal pad on the underside
of the chip.
The bias is max 12 uA! Compare the data sheet THS6012, the same chip. 5 kohm feedback may not be good. This is a current feedback amp and the feedback value is very sensitive.
 

jcx

Member
2003-02-17 7:38 pm
..
5 kOhm is "over-compensation" - since the current feedback op amp feedback R value ~ determines (inverse) GBW, this higher value slows down the amp, may make it easier to stabilize

12 uA could be too big a input current for noiseless, long life for volume pot wiper, OK if driven from a lower Z source
 
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