Dennis Field / dvk-mx8m-bsb - History

Make some minor fixes to various components' properties and update the BoM with the respective changes, sort the BoM based on reference designator and value

Replace SZMM5Z3V3T1G with MMSZ4688 zener diode which has a higher reverse working voltage to ensure that HP_DET is at a strong HIGH level when headphones/headset are inserted into the jack, replace its SOD-523 footprint with the corresponding SOD-123 footprint from the spec sheet's recommended land pattern

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.

Make recommended changes after reviewer examined pages 13, 15-20

Add pull-up resistor to nCS pin of the NOR flash chip, make electrolytic caps tantalums again due to a the price difference not being significant

Add mounting holes to the schematic and assign the associated M2 hole footprint, add fiducial marks to schematic and assign the associated 1mm diameter copper with 2mm diameter solder mask opening footprint, make various visual adjustments throughout the schematic

Update WWAN mPCIe sheet by organizing a few things and fixing the component properties order

Replace WWAN M.2 circuit with one intended for mPCIe modules, include 74LVC1G08 single 2-input AND gate, create the AND gate's footprint and use the official SOT-23-5 3D model

The mini-SIM slot will need to be replaced with one that has an active-LOW detection pin. Will want to see if we can find cheap electrolytic to replace a few of the tantalum caps with (not all since we still need some low ESR, high capacitance, low profile, caps).

For better BoM generation, added placeholders for SOM, disṕlay, camera, WWAN card and wifi/BT card.
Datasheet links and supplier information can be stored in these new library symbols.