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Multisim — NAND Only Logic Design

A PLTW Digital Electronics activity implementing a voting booth monitoring system using only NAND gates (74LS00). Starting from a truth table and K-map, Boolean expressions for Booth and Alarm outputs were derived, then re-implemented in NAND-only logic, simulated in Multisim, and prototyped on a Tinkercad breadboard with 74HC00 ICs.

Block diagram of voting booth monitoring system
Truth table and K-maps for Booth and Alarm outputs
Hand-drawn AOI circuits for Booth and Alarm
Multisim schematic screenshot of Booth and Alarm circuits
Hand-drawn NAND-only circuits for Booth and Alarm

NAND-Only Implementation

Both Booth and Alarm circuits were re-implemented using only 2-input NAND gates (74LS00), simulated in Multisim with switch inputs A, B, C, D and LED outputs, and prototyped in Tinkercad using 74HC00 ICs — verifying all input combinations against the truth table.

Conclusion: The NAND-only design required 5 full ICs and 3 out of 4 of an additional IC — proving NAND gates offer greater hardware efficiency than the AOI implementation.