ECET 105 Week 3 iLab Introduction to Digital Logic Gates

OBJECTIVES To understand basic logic functions (AND, OR, and NOT) and their complement used in Boolean algebra and digital logic design. To test simple logic small-scale integration (SSI) integrated circuit (IC) devices. II. PARTS LIST Equipment: IBM PC or Compatible with Windows 2000 or Higher Parts: 1 – 74LS00 Quad 2-Input NAND Gate IC 1 – 74LS02 Quad 2-Input NOR Gate IC 1 – 74LS04 Hex INVERTER Gate IC 1 – 74LS08 Quad 2-Input AND Gate IC 1 – 74LS32 Quad 2-Input OR Gate IC 1 – 74LS86 Quad 2-Input XOR Gate IC 1 – Set of Four Single-Pole-Double-Throw (SPDT) Switches, DIP Style 1 – 330 Ω resistor 1 – Light emitting diode (LED), red III. PROCEDURE OR Gate Operation Using the Internet or the campus library, acquire a hard copy of a data sheet for the 74LS32 quad 2-input OR gate. (HINT: Look at ti.com for possible help.) One of the OR gates is shown below in Figure 5.1. Figure 5.1 – 2-Input OR Gate Fill in the Table 5.1 for ALL possible logic conditions, based on the information found on the data sheet. Input (Pin 1) Input (Pin 2) Output (Pin 3) Table 5.1 - 2-Input OR Gate Theoretical Truth Table Write the Boolean expression below for the relationship between the device inputs (labeled as A and B) and output (labeled as Y). OUTPUT Y = ____________________________ Construct the circuit shown in Figure 5.2 (a layout of the breadboard is shown in Figure 5.3). Be sure that the flat side of the LED (called the cathode) is connected to ground and that the 74LS32 is connected to power and ground (Pins 14 and 7, respectively). Figure 5.2 – OR Gate Test Circuit Top View Side View Figure 5.3 – Breadboard Layout for Figure 5.2 Connect the circuit to verify the logic gate operation recording the input and output voltages. Fill in Table 5.2 below for ALL possible logic conditions. Input (Pin 1) Input (Pin 2) Output (Pin 3) Table 5.2 - 2-Input OR Gate Measured Truth Table Do the results match the manufacturer’s truth table? __________ (YES or NO) AND Gate Operation Acquire a hard copy of a data sheet for the 74LS08 quad 2-input AND gate. Figure 5.4 – 2-Input AND Gate Fill in the truth table below for ALL possible logic conditions based on the information found on the data sheet.