This expandable LED display for a microcontroller in Figure 1 has a simple interface with only 6 data/control wires and can be easily accommodated to a DIY design. The display has static indication.

Built a smart Li-ion charger with 10-LED fuel gauge. Features BQ24075 for charging & LM3914 voltage monitoring. Full build guide available! Tired of guessing your battery's charge level? In this ...