1. MUSIC DAC/ADC PCB Rick Raffanti Nov 23, 2010

2. Circuit changes Add ADR441 reference, U108 Add loopback filters Change U103 from LM1117-5 to LP3856-5 (lower dropout v, bigger pkg)

4. ADC chips- 2.6W each

5. Heatsink- thermal tape mount (couldn’t find screw-attach type)

6. Thermal plane model

7. Thermal model- 1 oz plane

8. Thermal model- Spice Placed power sources roughly where they are on existing designs, on 20cm by 12cm grid Used 5 ea 0.5C/W mounting screws each edge Used 23.7C/W junction- ambient for ADC chips

9. ADC chip junction temp rise Single 1 oz plane: L 49C, R 54C (above ambient) Single 3 oz plane: L 36C, R 42C Add 4 1C/W mounting points near each ADC chip (8 in all): –L 27C, R 28C Moved 1.8W regulator near RH edge- L 27C, R 28C Single 6 oz plane (=? 2 3oz planes): L 18C, R 19C