The recent modifications made to the circuit board design have improved its functionality and space efficiency. Initially, the replacement of 0805 passive components with 0603 variants was implemented. This transition not only saves space on the board but also contributes to a more compact overall layout.

Additionally, the rearrangement of components was undertaken to facilitate a clearer and more logical trace arrangement. In addition to the clearer arrangement, the CCD side of the PCB was kept clean. In the previous version of the board, I left the footprint outlines on the board which looks really bad, especially on a black PCB. Also, it may be just overthinking, but the white silkscreen might cause unwanted reflections of stray light.

One of the key changes was the resizing of the breakout board to closely match the dimensions of the STM32F401CCU6 microcontroller board. This alignment not only promotes a more streamlined design but also aids in maintaining a consistent aesthetic across the entire assembly. The reduction in board size was accompanied by a decrease in the number of mounting holes—from four to two. This reduction simplifies the assembly process while still ensuring that the board remains securely mounted.

To maximize performance, certain pins were reassigned following minor adjustments in the firmware. These adjustments are pivotal as they allow for better functionality and efficiency of the circuit. Coupled with the pin reassignment, the decision to orient the STM32 board upwards from the surface of the breakout board plays a dual role.

In conclusion, these design modifications reflect a comprehensive approach to optimizing the circuit board for both space and performance.

Pin connections for relevant pins:

fM: PA6

ICG: PA5

SH: PA3

OS: PA1