2 bit down counter

hamm

New Member
i have design a two bit down counter it works well in simulation but when i patch it on breadboard it doesnt count can any one figure it out whats wrong i have attached the circuit in doc file pls see it
 

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On CMOS circuits you can't leave any inputs floating. Tie them to either Vdd or Gnd.
 
Did you connect power & ground to the flip flops & the decoder ICs?
 
thx for reply
yep i observed on simulation when i connect the above circuit to 9v battery once i connect the 7 segment(common cathode) to -ve terminal it becomes short on the other hand when i give a separate ground to seven segment it start counting wts the reason ov it wt should i do on bread board
 
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