CD4017 - Decade Counter IC
The CD4017 IC is a decade counter that counts to ten. It has 10 outputs that represent the numbers 0 to 9. The counter increases with one for every rising clock pulse. After the counter has reached 9, it starts again from 0 with the next clock pulse.
This is a great chip for making running LEDs! See a circuit example further down.
check out : Dual Complementary Pair with Inverter IC - CD4007
Pin Overview:

Pinout of CD4017 - Decade Counter IC
Pin Name |
Pin # |
Type |
Description |
VDD |
16 |
Power |
Supply Voltage (+3 to +15V) |
GND |
8 |
Power |
Ground (0V) |
Q0-Q9 |
1-7 and 9-11 |
Output |
Qx is high when the counter is x |
CO |
12 |
Output |
Carry Out. Goes high after ten clock pulses |
CI |
13 |
Input |
Clock Inhibit. Ignores clock inputs |
CLK |
14 |
Input |
Clock Input. Increases the counter with one |
MR |
15 |
Input |
Resets the counter to 0 |