Dennis Field / dvk-mx8m-bsb - History

Use I2C3 bus instead of I2C1 bus based on EmCraft's feedback

Move the VBUS TVS diode and bypass caps and place copper pour on the respective pad areas, the VBUS rail has a 6mm wide fill zone in order to properly handle ~4.3A with a <10degreeC temperature rise (should also do this when bring VBUS to the charge controller), make the In4.Cu layer a solid ground layer

Move CAPTOUCH_~RST from BOOT_CFG_03 to GPIO1_IO05/P3.33 (was CSI_P2_PWDN), add a 10k pull-down to LCD_~RESET, make the corresponding changes to the BoM and netlist/layout

Having CAPTOUCH_~RST on BOOT_CFG_03 caused a voltage divider on the pin.

Route the PTC polyfuse that's on the VBUS rail using a copper pour on the In4.Cu layer, route the USB-C's shielding to parallel 0Ohm and NC cap to GND, add a power net class, add a 0.508mm annular ring 0.254mm drill via for power nets

Make some minor aesthetic adjustments to the USB-C schematic sheet, the USB-C receptacle symbol should come from the dvk-mx8m-bsb library

Re-labelled signals around USB-C with naming scheme for differential routing (_P/_N names).
Routed some data lines behind USB connector.

Rename all diff pairs such that they end in _P/_N rather than just P/N (underscore needed for diff pair routing)

Add component info for 10k resistors that are missing them (R105 & R220)

Replace camera's schottky+resistor level-shifter circuit with the more functional TXB0101 dedicated IC

Add proper WWAN reset circuit using a MMBT2222A NPN BJT along with a 100nF cap and a TVS diode, make needed adjustements to the WWAN's SIM card circuit (UIM-CLK and UIM-RESET caps are NC & added 4.7k series resistor to SIM_DETECT_O#), assign the MMBT2222A footprint to KiCad's official SOT-23 footprint (identical to the spec sheet's recommended land pattern)

If necessary, the NC cap pads on UIM-CLK and UIM-RESET can be tested with various values during the first prototype debugging phase.