Logic Diagram Of 4 Bit Comparator

Using cmos logic style fig 3 a represents symbol of cmos inverter.

Logic diagram of 4 bit comparator. 2 2 logic diagram according to logic function obtained from truth table logic diagram is drawn as in fig 2. A 3 b 3 being the most significant inputs. Addition subtraction shift operand one bit magnitude comparison plus 12 more it also implemented several logic operations. The hcf4063b is a low power 4 bit magnitude comparator designed for use in computer and logic applications that require the comparison of two 4 bit words.

Exclusive or comparator and nand or nor plus 10 more here is the logic diagram. 3 20 april 2018 product data sheet 1 general description the 74hc85. It used 75 gates. 5 gates of and have different number of inputs but the principle of layout is the same.

2 bit magnitude comparator design using different logic styles 3 1. So we will do things a bit differently here. In a 4 bit comparator the condition of a b can be possible in the following four cases. The two 4 bit numbers are a a3 a2 a1 a0 and b3 b2 b1 b0 where a3 and b3 are the most.

We will compare each bit of the two 4 bit numbers and based on that comparison and the weight of their positions we will draft a truth table. The hcf4063b has eight comparing inputs. It consists of eight inputs each for two four bit numbers and three outputs to generate less than equal to and greater than between two binary numbers. They perform comparison of two 4 bit binary bcd or other monotonic codes and present the three possible magnitude results at the outputs qa b qa b and qa b.

4 gates of xor are the same. The logic circuit of a 2 bit comparator how to design a 4 bit comparator. 4 bit magnitude comparator rev. So does the nor gate.

By the way they re still available from some distributors such as newark and mouser. 74hct85 is a 4 bit magnitude comparator that can be expanded to almost any length. An equality comparator such as that illustrated in fig 4 3 1 is the simplest multi bit logic comparator and can be used for such circuits as electronic locks and security devices where a binary password consisting of multiple bits is input to the comparator to be compared with another preset word. Figure 2 5 optimized logic diagram for a 4 bit comparator seeing from the above diagram we can use 11 gates to implement the 4 bit comparator beside the inverters.

The truth table for a 4 bit comparator would have 4 4 256 rows. This logic circuit determines whether one 4 bit word binary or bcd is less than equal to or greater than a second 4 bit word. Logic diagram of 2 bit magnitude comparator 3. Operation is not restricted to binary codes the device will work with any monotonic code.

The kind of gates includes xor and nor. The figure below shows the logic diagram of a 2 bit comparator using basic logic gates. It consists of one nmos one pmos. 4 bit magnitude comparator the sn54 74ls85 is a 4 bit magnitude camparator which compares two 4 bit words a b each word having four parallel inputs a 0 a3 b 0 b3.