Hi,
This is my first post in the forum. I don't have a significant background knowledge on circuits but need to understand the attached circuit diagram. I didn't have anyone to turn to, so after much frustration trying to understand it by myself and googling around, I arrived here to ask for help from you all. Thank you in advance.
The circuit is a simple keypad lock that uses 3 AND logic gates and opens upon punching the code ABC in that order. What I don't understand is the role of the resistors. Are they needed to prevent a current overflow? R5 probably serves that function. But it isn't immediately clear what other four resistors do. Do R1-4 all serve the same purpose or not? Are they needed for the "memory" function of the loop (i.e. the circuit has to remember that the key "A" was pressed even when the key is no longer being pressed down)?
In other words, what would happen if the resistors were not there?
This is my first post in the forum. I don't have a significant background knowledge on circuits but need to understand the attached circuit diagram. I didn't have anyone to turn to, so after much frustration trying to understand it by myself and googling around, I arrived here to ask for help from you all. Thank you in advance.
The circuit is a simple keypad lock that uses 3 AND logic gates and opens upon punching the code ABC in that order. What I don't understand is the role of the resistors. Are they needed to prevent a current overflow? R5 probably serves that function. But it isn't immediately clear what other four resistors do. Do R1-4 all serve the same purpose or not? Are they needed for the "memory" function of the loop (i.e. the circuit has to remember that the key "A" was pressed even when the key is no longer being pressed down)?
In other words, what would happen if the resistors were not there?
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