fixed upconverter termination and LPF

ready for production
added variants

No PI simulation and copper balancing yet

No PI simulation and copper balancing yet

initial layout done
ADC channels swapped for easier routing
Added TVS diodes to EEM I2C
TR5 part number added on schematics
LD7 and LD22 LEDs merged into LD7 (both used only one LED)
Added missing GND net to AVDD33 decoupling caps