Yet another ultra low noise high PSRR LDO - LT3042

It has. But if you do not have a big output currend and/or voltage drop (= minimal power dissipation) you do not need to solder it. Or: you can make a bigger via under the IC and use a little solder paste befor placing the component. After soldering some pins you can heat the thermal pad from the bottom side.
 
My take on LT3045 pcb. Bottom layer has a big exposed copper pad for attaching a heatsink. The ones dedicated to raspberry pi should fit fine.

I'm waiting for the PCBs to arrive from OSH park. I'll post an update when I receive them :)
 

Attachments

  • lt3045.jpeg
    lt3045.jpeg
    182.5 KB · Views: 944
Nice work kalinowski. Which rpi would you tweak? I did 2B and 2B+ on dual LT3045-1A regs but now i want to Do it on 3+ but there you have 1,2V High current pin for CPU that should have 4A pulse power...
Unsoldering switching regs and connecting to linear is big improvement in terms of get away from digitalisssss ssss sound.
 
It's a pity it's close to impossible to replace the Raspberry's switching internal regulators for linear ones, as that might be good for the audio quality.


The RPi is generating huge amounts of hash in every digital chip, there's little point cleaning up its rails as every load is pumping noise into them, you need separate analog ground and supply rails from the digital ones for analog interfaces.
 
"The optimum load cap for the LT3042 is 4.7uF. Overdoing gets you a noise peak. There is a trace with 22uF."
Low noise regulator for DAC & clock

"The LT3042 wants its 4.7uF output capacitor to have just that value.
Departing in either direction creates noise peaks at high frequencies, but still with an absolute value the others can only dream about."
Mr. Jung's ultra-low noise VREF - the GLED431


Patrick