LCD Screen Driver with 74HC595 (for LCDs with 2x8 header).
This uses the 74HC595 to drive LCD displays such as 1602, 1604, 2002, or 2004 with 5V, GND and three Arduino pins (DIN, CS, and CLK). Compatible with screens that have 2x8 male header.
It is recommended to use a 2x8 male header on the LCD and 1x8 female socket on the Serial_LCD_Driver_2.
Note that in the KiCad files male header is used (although the 3D .png rendering shows how the female socket should be populated), because I wanted to have pin for pin maping (ignore the 3D rendering in the KiCad files).
The LED (D1) and R2 are optional. You can populate for diagnostics (test the hardware), or connect a panel LED with wires to the Serial_LCD_Driver_2.
It is recommended to use a resistance value for R2 no lower than 470 Ohms (preferably use 1K with high efficiency LEDs).
The Q1 is used to provide current for the LCD back-light, so that the 74HC595 does not bear the burden to provide the required back-light current (some LCD back-lights draw as much as 200mA). The R1 can be adjusted (1K to 10K) to achieve Q1 saturation for or reduce the current to a desired brightness.
This design has been built and tested with the code provided in the Serial_LCD_Driver repository. It works!
