Question On V5A & V5D Of TA2020

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I plan to replace the internal generated V5A and V5D of TA2020 by an external low noise 5V supply. Due to there is R-C-R filter in that 5V supply, the 5V will be stablized at around two seconds after the main power is turned on.

So when my 41Hz AMP6 is turned on, the VDD (14.5V) will be supplied to TA2020 immediately while the V5A and V5D will be ready after two seconds. Will this damage the TA2020 or any problem will arise ?

Thanks for your advice in advance.
 
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I can't remember exactly what happens if you power up the 12V supply before the 5V supply (most likely you'll get a loud turn on thump), but the recommended power on sequence is 5V followed by 12V or you can power up both at the same time.

If you power up the 5V supply without the 12V supply the overload and fault indicators will trigger. They go away once the 12V supply comes up without any harm to the chip. You will want to tie all of the 12V pins together otherwise you risk damaging the chip if the voltage differential between the pins gets too high for some reason (powering up is one instance where it could happen). On my first version of the Ref-T I had every power pin separated. The amp worked but you have to make sure all the 12V pins see very close to the same voltage and V5A and V5D see very close to the same voltage. They are weakly connected internally (the 12V pins to each other and the 5V pins to each other) and a large voltage differential can cause those weak connections to blow like a fuse and damage the chip. I would recommend connecting V5A and V5D, just use decoupling caps close to each pin. Unfortunately Tripath wouldn't disclose any more information so hopefully that information helps.

You can read all about the Ref-T here: http://www.diyaudio.com/forums/showthread.php?s=&threadid=77520&perpage=10&pagenumber=1

The first 5 or so pages are about the first design (you can see what kind of issues I was having) and after that the revised design is discussed.
 
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