about numeric keyboard questions?

[nick]

i use many diodes to make a numeric keybord , total are 12 keys,the
keys connect to other ICs when i connect DC9v to this circuit , and
press the key
i divcover become less 9v but the ic need 9v to operate , Are the keys
make potential difference in the circut how to solve this problem, to
provide a stable voltage to the circuit when i press the keys?

thanks

 

[the Wiz]

i141802596@yahoo.com (nick) wrote:

i use many diodes to make a numeric keybord , total are 12 keys,the
keys connect to other ICs when i connect DC9v to this circuit , and
press the key
i divcover become less 9v but the ic need 9v to operate , Are the keys
make potential difference in the circut how to solve this problem, to
provide a stable voltage to the circuit when i press the keys?

thanks

There is a voltage drop across each diode that is in the circuit when a key is
pressed, typically from 0.2 to 0.6 volts depending on the type of diode.


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