How can PTH resistors in a PSU sound different from SMD?
This would be much better on a two layer board with a ground plane underneath for both noise, heat removal and better regulation. Further the resistors are feedback so smaller less inductive SMD would be better. The ground connections to the device are too small so it may overheat in use.....
This would be much better on a two layer board with a ground plane underneath for both noise, heat removal and better regulation. Further the resistors are feedback so smaller less inductive SMD would be better. The ground connections to the device are too small so it may overheat in use.....
TI have very specific recommendations for this chip - If you want to obtain anything like its datasheet specs, layout is very important for lots of reasons, not least is planning the thermal budget correctly (hint: you have no heat sink plane).
As NO AUDIO is passing though any of these devices, use of PTH vs. SMDs will have absolutely no effect on the resulting sound - what DOES matter is the output decoupling & filtering.
Read the datasheet fully. Look at the example board that TI provide. Note the rationale for the various component & layout design decisions.
As NO AUDIO is passing though any of these devices, use of PTH vs. SMDs will have absolutely no effect on the resulting sound - what DOES matter is the output decoupling & filtering.
Read the datasheet fully. Look at the example board that TI provide. Note the rationale for the various component & layout design decisions.
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yes the perforated heatsink on the base of the part is left to do but.
Agreed regarding the heat Im using a external heatsink on the IC.
Does copper sucks out heat faster?the difference between the alu and copper in the amount of dissipation is very little but the faster heat sucking is copper?
Agreed regarding the heat Im using a external heatsink on the IC.
Does copper sucks out heat faster?the difference between the alu and copper in the amount of dissipation is very little but the faster heat sucking is copper?
If you are thinking of using a heat sink on the top surface of the part, you are not going to remove the heat.... The heat is removed from the die by using the thermal pad... and by the correct use of thermal vias.
Your starters:
http://www.ti.com/lit/an/sloa122/sloa122.pdf
http://www.akrossilicon.com/home/su...racterization-and-qfn-layout-guide-rev0-6-pdf
http://cache.freescale.com/files/sensors/doc/app_note/AN4530.pdf
and IPC-7093 if you can find it.
You have already nice pcb made by Mravlcax. Works excellent. I always use 600ohm or 100-150uh ferrite bead after reg. for more smoth refined sound.
http://www.diyaudio.com/forums/vendors-bazaar/263618-tps7a4700-low-noise-ldo-regulator-pcb-8.html
http://www.diyaudio.com/forums/vendors-bazaar/263618-tps7a4700-low-noise-ldo-regulator-pcb-8.html
Below, yes if you are able to mount the device upside down to reach its heath conductive bottom and be able to connect it to the heathsink. Sure.
Regards
Then they are wrong, I don't recall seeing any design with a heat sink on the top for these sort of devices (Plastic QFN or QFP's).
The first page of the first link shows the problem of a heat sink on the top... the heat has to go through the plastic, the thermal resistance is huge. The die is mounted upside down on the thermal pad to give the best possible thermal path for the removal of heat directly from the die.
Generally if you look at the data sheet there will be a graph of copper area the device is soldered to and the power and thermal derating etc.
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