Modify the CSI circuit to use a 02x15 connector for potential use with the CO8725-B5SA-E camera, include cap touch FPC connector details, make minor adjustments to GNSS antenna circuit

Add WWAN and WLAN+BT MHF4 coax connectors and antennae symbols to the schematic, remove home and back buttons, reorder sheets so that GNSS is above the haptic motor sheet

Add camera/CSI circuit, include second switch that is part of the audio+camera DPDT for killing both simultaneously, level shifters used for camera's I/O that requires it, footprints for a 1.8V LDO which may be used by DVDD will be included

External DVDD (1.8V LDO) needs to be tested if it's needed (datasheet says an internal DVDD can be used, as is the case with Boundary Devices' OV5640 camera).

Replace ICM-20948 IMU with the LSM90S1, replace RPR-0521RS prox+ambient light sensor with the VCNL4040

Nearly complete the LCD/DSI and cap-touch schematic, add notes from the display's datasheet regarding the various pin assignments, add component property information for the 39-pin DSI clamshell connector

Still need to determine what this requested "low power state signal" requirement is for the display.

Add LCD display's 22.4V (@40mA) LED backlight driver/boost converter IC circuit (PAM2841), selected the rectifying/schottky diode (SS14), and set the OVP to 37.6V as found on the IC's EVB

Modify the boot config/boot mode pins and switch such that only eMMC and USB (serial downloader) are boot options due to the uSD being attached to the USB<->SD bridge chip, add OV5460 notes about using the internal DVDD 1.5V regulator

Make changes to the USB hub + SD bridge circuit and uSD sheet based on Prolific's feedback after asking questions

Add smart card circuit using the SEC1110 USB to ISO/IEC 7816 bridge chip, include ID-0001/2FF/mini-SIM socket connector selection informatino (1010027182)

Need to create footprint for the mini-SIM socket

Add Prolific MA8627 USB hub + SDIO bridge chip and use it in place of the USB2660, SD interface used with the uSD (not WLAN)

Move MIPI DSI & CSI sheets into a "MIPI" sheet, both DSI and CSI will likely use the I2C level shifter

Begin assigning footprints to passive components, add component information to the common 10k resistors throughout the schematic, include TVS diodes on the switch/button I/O pins, use the DB2J20900L schottky diode throughout the design (in place of the ZLLS400)

Added notes about the battery holder, battery size, and the fact that the 103HT thermistor can fit underneath the 18650 battery when the battery is insterted into the holder.

Included frequency response curve for the new/cheaper SMD speaker (slightly thicker mechanical dimension).

Included note about the RedPine RS9116's SDIO_RESET# line expecting a 2.31V VIH logic level, increased the pull-up to 100k (M.2 standard states that this is should be 1.8V level).

Added a TODO note stating the 1.8V logic-level I2C devices should share the same level-shifter that will be on the top-level circuit (in next commit).

Flip the direction of FULL_CARD_POWER_OFF# and W_DISABLE*# switches such that the devices are on when the switch is open, this should ever so slightly reduce the power consumption when these devices are used (most likely more often than them being off)

Connect the USB/SDIO bridge to WLAN rather than the uSD, fix a few ERC violations (not has zero errors/warnings), use best schottky option

Add current sense resistors and jumper symbols in the schematic, assign the various signals left unspecified, complete the PWR_EN assignment and verify that thepower sequence would be brought up in the correct order, add an LED to the VBAT_REG rail for debugging purposes (know when the board is receiving power)

Both the GP_LED1 and the HAPTIC motor are able to be controlled via PWM2 by individually MUXing the corresponding pads to PWM2. Only one pin should be MUXed to PWM2 at a time whilst the other is a GPIO, otherwise they will behave identically.

The I2C buses do not need the bus switch found on the EmCraft baseboard since the M.2 modules' power is controlled by PWR_EN and their I2C is level shifted between 1.8V<->3.3V, making it safe to leave them as is.

The various sense resistors have their corresponding parts selected but will be "NC" in the BoM and will not be assembled during manufacturing. To measure the current on the various rails (and WLAN M.2), one will need to break the trace between the two pads and place the corresponding resistor. A jumper (1.27 or 2.45 still needs to be determined) can be used to re-short these pads.

Notes have been added regarding which GPIO pins can easily be interchanged if it improves the layout.

Selected a better/cheaper RJ45 receptacle. Also picked out a well-suited green LED to be used in various spots throughout the board.

Include power load switch ICs to the 3.3V and 5V rails so that the SoC can disable the peripherals' power using the PWR_EN signal

Need to verify that 3V3's capacitance is greater than 3V3_P!

Next step is to have PWR_EN control the various logic translator chips EN pins.

Use a DP3T switch to select between eMMC, USB (serial download), and uSD boot devices, corrected the SW_BACK and SW_HOME buttons to have 33Ohm pull-ups instead
of pull-downs since the respective boot config lines have pull-downs already set

These buttons should be untouched during boot otherwise the board will not boot properly (pressing SW_HOME during boot causes "SD power cycle enable/eMMC reset enable" and pressing SW_BACK causes the uSD to be treated as a 4-bit bus if it's the boot device otherwise it's a BOOTCONFIG[6:4]=011 "reserved" condition)

Assign SAI5 to the WLAN/BT M.2, remove SIM2 slot due to conflicts between modules (specifically the L830-EB being a Config_0 module where the TX_BLANKING signal would connected to USIM_PWR2 sink), reassign the corresponding M.2 config pin to handle HP_DET, remove the AMOLED buck-boost as a different regulator will be used

The MIC_SEL, PROX_~INT, IMU_INT, and HAPTIC signals still need assigning

AND

Since pin 54 is actually USB_VBUS sink on the RedPine module the baseboard may need to treat this pin specially (NXP EVK uses a NMOS inverter with a 10k pull-up to 3V3).

Using a PFET to switch the high-side. The motor will likely be coin-shaped with adhesive on the back to stick to a designated spot on the board and have a 2-pin Molex or JST connector installed on the wire leads (by request).

Add NOR flash chip schematic, use mini-HDMI (requested) instead of micro and add its corresponding properties and footprint, use 3.5mm CTIA headset jack with through-hole pins rather than an SMD one for extra "mechanical rigidity"

Will likely want to use a USB-C receptacle with through-hole shield pins.

Add +X direction in the IMU's footprint on the F.SilkS layer, include figures in the schematic which show the corresponding axis directions (for both gyro/accel & compass) with respect to the package's pin 1 indicator/indent

Also double checked the footprint's pad sizes against the given package dimensions (no landing pattern given).

Add Proximity+Ambient Light sensor and 9-axis IMU circuits to the "sensors" schematic sheet, include the associated footprints and assign them to the respective symbols

The 9-axis IMU is configured to use I2C(1) rather than SPI. Notes are included regarding the IMU's setup. Descriptions of the IMU state that it is "fully compliant with Android" and therefore drivers must be available.

og SPDT switch to select internal or external mic via software (GPIO), select sp
ecific 8Ohm SMD speaker and SMD -37dB passive 2 terminal microphone (2.2kOhm output impedance)

Also fix a small typo in the notes from the last commit.

Introduce a method to switch between built-in and headset microphone depending on the presence of something plugged into the 3.5mm headphone jack, included notes regarding measurements, simulations, and various findings for the headset/built-in mic opperation

Zener diode included to protect the GPIO pin against under/over voltage from HP_OUT. Schmitt-trigger inverted at the enable pin of the analog switch for some debouncing.

Continue with the audio CODEC schematic, selected a potential STIA 3.5mm headphone jack, use logic level shifters on the WWAN/BT M.2's UART and PCM interfaces since the M.2 spec states that these are 1.8V logic levels

Still need to assign the corresponding SAI interface for the BT.

Assign verious signals such as W_DISABLE1, W_DISABLE2, WWAN_DISABLE; reorder the hierarchy to make more sense; add "solid" graphic lines around the power signals on the top sheet for clarity

Organize the USB-C, Battery, and Power sheets at the top-level such that the power-flow makes more sense when reading the schematic

Add I2C interface to WiFi/BT M.2, select an appropriate dual 2-input AND gate IC for the W_DISABLE logic and add the corresponding debounce/pull-down circuit to the HKS for W_DISABLE

Notes have been included regarding the I2C logic level voltage. If the USB interface is used then the input voltage needs to be 5.0V (not 3.3V); therefore the USB interface and hub may need to be removed!

Several signals are unused by the RS9116 WiFi/BT module, as noted in the schematic.

Add demultiplexer to uSDHC2 for the uSD and WiFi's SDIO interfaces, include the DEMUX's (TS3A27518E) 24QFN footprint

Begin WiFi+BT M.2 socket circuit, connect the associated USB bus from the hub circuit, determined that the i.MX8M's UART's default POR state is such that CTS is an output and RTS is an input and assigned the signals accordingly