Add electric circuit design

README.md

@@ -1,2 +1,25 @@
 # GlassBluetoothSpeaker
 
+## Hardware
+
+* Raspberry Pi Zero W V1.1
+* [DAC: JustBoom DAC Zero pHAT](https://shop.justboom.co/products/justboom-dac-zero-phat)
+* [10cm/4in fullrange speaker 4ohm: Visaton FR 10](https://www.visaton.de/en/products/drivers/fullrange-systems/fr-10-4-ohm)
+* [Digital Mono Amp: OEP30W](https://www.ebay.de/itm/174942134102?chn=ps&norover=1&mkevt=1&mkrid=7071533165376683&mkcid=2&itemid=174942134102&targetid=4582833206194173&device=c&mktype=&googleloc=&poi=&campaignid=376712745&mkgroupid=1267737623409783&rlsatarget=pla-4582833206194173&abcId=9300540&merchantid=87778)
+    * Small passive ic chip cooler
+* DC-DC adjustable step down module: CN4015-1
+* SD card
+* AC-DC power supply with at least 12V output
+    * DC power jack
+* Potentionmeters to adjust sound level and led brightness level
+* Resistors
+* Switch
+    * general power switch
+    * light switch
+* [LED filament](https://en.wikipedia.org/wiki/LED_filament)
+
+## Software
+
+## Reference
+
+## STL / 3d printing