Hi, I'm making a PCB for my line following - color sorting robot which includes a few buck regulators, 1 ATmega328P master, 1 ATmega328 Slave, 1 APDS 9960 color - proximity sensor, 1 motor driver TB6612 and pin headers for ICSP communication with Pixy Camera, and FTDI ports to write to the MCUs. The schematic and the board are shown below. Generally, please check my wirings... Specifically, my concerns are as follows:
1. I use I2C to communicate between 1 master and 2 slaves (1 Atmega and 1 sensor), I2C connection requires pull up resistors to a logical high, the APDS9960 module takes in 3.3(V) supply, can I use this 3.3 V for I2C between the ATmega master and slave as a logical high as well?
2. In the datasheet the ATmega328 draws a 0.2A current when operating in active mode at 1MHz, does it also draw the same current operating at different frequencies? How do I know which frequency it's operating at? Is it determined by the crystal I connected it to?
3. I have placed some 5730 LEDs to assist the APDS9960 module, however the foot print and schematic has 3 pins out...? What's the third pin?
4. Please check my general wiring as in I2C, UART and SPI connection.

 

Yes I have received many advice on changing the 14.8 - 3.3 V buck to a 5 - 3.3 V regulator. I will try to implement this as soon as possible. But first, I need to see if this schematic is legit. Also I intend to have all the line width of the PCB at 0.8mm to ensure safe current flow. I repost the two parts of the circuit here so that you guys can see clearer