DIGITAL ELECTRONICS COURSE, SPRING 2008 1 Abstract—This report consider logic of some gates like NOR, NAND, XOR, INVERTER (NOT), MUX 2 to 1 and also D- LATCH and D-FLIPFLOP constructed from above gates. I. INTRODUCTION ost important subject in of digital electronic components is that the component work true functionally and other parameters are in lowers degree of importance.Here we’ll simulate functionally some logical components with CMOS technology in VERILOG l anguage. We’ll consider NOR, NAND, XOR, INVERTER (NOT), MUX 2 to 1 in A section and D-LATCH and D-FLIPFLOP in B section and results will be available in appendix part. II. SOME NOTES A. Sections NOR Logic Gate: In boolean logic, logical nor or joint denial is a truth- functional operator which produces a result that is the inverse of logical or. That is, a sentence of the form (A NOR B) is true precisely when neither A nor B is true. Fig. 1. NOR symbol [1]. XOR Logic gate The XOR gate (sometimes EOR gate) is a digital logic gate that implements exclusive disjunction. A HIGH output (1) results if one, and only one, of the inputs to the gate is HIGH (1). If both inputs are LOW (0) or both are HIGH (1), a LOW output (0) results [1]. Fig. 2. XOR symbol [1]. NAND Logic gate: The NAND operation is a logical operation on two logical values, typically the values of two propositions, that produces a value of false if and only if both of its operands are true. In Submitted May 3, 2008. other words, it produces a value of true if and only if at least one of its operands is false. Fig. 3. NAND symbol [1]. INVERTER: In digital logic, an inverter is a logic gate which inverts the digital signal driven on its input. It is also called NOT gate [1]. Fig. 4. NOT symbol [1]. MUX 2 to 1: In electronics, a multiplexer is a device that performs multiplexing; it selects one of many analog or digital input signals and outputs that into a single line [1]. Fig. 5. MUX 2 to 1 symbol [1]. B. Section D-LATCH: It is also known as transparent latch, data latch, or simply gated latch. It has a data input and an enable signal (sometimes named clock , or control). The word transparent comes from the fact that, when the enable input is on, the signal would propagate directly through the circuit, from the input D to the output Q. Fig. 6. D-LATCH symbol [1]. Switch Level Simulation Mohammad Reza Najafi 810184285 M