PB Fortich

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  • Pushbutton Winner Indicator

  • Created: Jan 16, 2015

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This simple project is commonly used for entertainment. It identifies the first person to trigger or hit the switch and lock out the other entries. It generates buffered outputs and double diode protection on all inputs of the NAND gates. It is simple and low cost that can handle up to four participants.

The circuit is comprised of SN74LS75 4-BIT Bistable Latches that stores information temporarily. It is used with MC14012B dual 4−input NAND gates that indicates the first button being pressed and locked out other inputs. The LEDs are provided as indicators of pushbutton switches. It lights up the pushbutton that is pressed first while other stays OFF. The pushbutton switches are for the user input with pull-up resistors to ensure correct logic levels of the system.

The design is suitable for simple queuing system, which manages a certain number of participants. It is more convenient to identify queues using this system. It is not limited only to entertainment applications but it is also useful in processing data, objects, or even events that requires sequential collection or other forms of queue.



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