There is a cheap way to get 20 from 8 is to use two 7445's 1 of 10 decoder IC's
To get no outputs on, you would need to issue an invalid BCD code, the outputs will drive 80ma at up to 30vdc.
Al.
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CNC, Mechatronics Integration and Machine Design.
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E. |