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I need help with a circuit design

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New Member
hello dear sir
I've made the Digital Up/Down Selector with 74hc193 and 74hc154 for 16 switching output for variable power supplay
push up/down key but output 74hc154 random swithing for example jumping output 74154 from 1 to 3 or 6 or 16 switching
power supply 7805 and capacitance 100uf and 100nf and input used gate 4584 but yet problem
Please help me another circuit without 74hc193 and no use microcontroler ic simple circuit


Well-Known Member
Most Helpful Member
Can you scan in your schematic and post it.
Your problem is "key debounce" or switch debounce. The switch probably does not open/close cleanly. So it will have two or three (on/off) from one switching.
Please show switch and the circuit up to the counter.
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