This project is described at Hackaday.

The minimum lines required to use this board are: GND, SER (data), SRCLK (shift), RCLK (strobe). Vcc depends on the power arrangement. You should jumper the ~OESEL (output enable select) to ground if you don't wish to disable the display by signal, or vary the output with PWM, from a controller. The ~SRCLR input is only needed for resetting the output by the controller.

This board is designed with optional aspects you can choose to include or not:

• As mentioned some lines don't need to be driven in smaller configurations.
• Between 1 and 4 74HC595s can be installed for 8-32 outputs, in steps of 8. Naturally only the resistors for the used outputs need to be installed.
• The 74HC595 can source or sink 6 mA current.
• The 74HC595 can operate between 2V and 6V. This can be chosen to suit the controller, e.g. 3.3V or 5V, and the power supply section if installed.
• The power supply section is optional. You can choose to power this from the controller. Or you could power the controller with this.
• Copper pads for data and output are duplicated so you can attach more connectors or even solder wires. The input power is also brought out to duplicate pads for piggybacking to other circuits, e.g. an auxiliary board.
• Although the connectors are rendered as vertical pin headers, you can use other kinds of connectors like pin sockets, or even solder wires to the pads.