IC 4026 Decade Counter/Divider

The IC 4026 Decade counter combines a counter and a display driver into a single chip. The counter is a decade counter, which means it counts from 0 to 9 before restarting. Internal logic converts the count to the seven outputs (a - g) necessary to drive a 7-segment display. The outputs can provide a few mA of current, enough to directly drive a small 7-segment LED display.

When the CLOCK input (Ck) changes from LOW to HIGH, the output changes. The counter output changes when the clock input rises.

The RESET (RST) button resets the counter to zero, and as a result, the display displays zero. RESET is usually set to LOW. When RESET is HIGH, the counter is reset to zero. The counter does not count clock pulses while RESET is HIGH.

CLOCK ENABLE (CE) is typically set to LOW. When CE is LOW, the counter responds to clock pulses and advances the count with each rising edge of the clock. The counter does not respond to clock pulses and the display does not change when CE is HIGH. Clock pulses are ignored while CE is HIGH.

DISPLAY ENABLE (DE) is typically set to HIGH. When DE is HIGH, the outputs a to g supply current to the display, illuminating the 7-segment display. When DE is set to LOW, all outputs a through g are set to LOW, and the 7-segment display is blank, with no segments illuminated.