This Design Idea is a 1-dot bar graph display that provides a simple, compact, low-cost, and low-power alternative to the usual four-LED bar graph battery gauge [1]. It consists of a surface-mount ...

The circuit in Figure 1 uses only five I/O lines to drive a dot- or bar-graph display of 20 LEDs. Although this version of the design uses a small and inexpensive one-time-programmable microprocessor, ...