CD4017 Decade Counter circuit

 

The above circuit is for decade counter. These circuits are typically used for LED chasers and counting operations.

• The output of the decade counter increments base don the clock input
• On every clock rising edge, the output transitions
• Initially, when there is no clock or CE is high, the outputs Q0 to Q9 are low
• Once the circuit receives clock input, on the rising edge, Q0 becomes HIGH
• For the next rising edge of the clock, Q1 shall be high and all other outputs go low 
• The sequence continues till Q9 goes high and starts again from Q0
• TC is a Terminal count output which is used to sync various decade counters

The circuit operates based on the below truth table:

 The out waveform from the circuit is as below: