That depends on the technology (e.g. TTL, CMOS, ECL) used in the adder. Look on the data sheet tables for the exact device you are using. There will be several different delays listed, depending on which inputs and outputs are involved. Also minimum and/or maximum delays may be given instead of typical.
A half adder has 2 inputs and 2 outputs, these are usually called something like: Ain, Bin, Sout, Cout.A full adder has 3 inputs and 2 outputs, these are usually called something like: Ain, Bin, Cin, Sout, Cout.A & B are the 2 bits to be added, C is the carry bit, and S is the sum bit. A half adder cannot propagate carry as it has no carry input, a full adder canpropagate carry. A full adder can be built from 2 half adders.
A full adder takes two inputs plus carry in and produces one output plus carry out. You need four full adders to add two 4 bit words. (No half adders required.)Or: for the lowest bit you can use a half-adder (no input carry).
The parallel counter incorporates carry lookahead circuits so that all flip-flops in the counter change in sync with the clock pulse. The ripple counter each flip-flop output is the clock for the next flip-flop, causing the most significant bit of the counter to settle only after a long delay time from the input clock pulse.
just one
=HA#0-=FA#1-=FA#2-=FA#3-=FA#4-=FA#5-=FA#6-=FA#7=It consists of seven Full-Adder and one Half-Adder, has 2*8 input lines and 9 output line (8+carry).
The parallel adder which we use in the digital circuits ,the carry output of each full adder stage is connected to the carry input of the next higher order stage.therefore,the sum and carry outputs of any stage cannot be produced until the input carry occurs; This leads to a time delay in the addition process.This delay is known as carry propagation delay. to the second question the propagation delay can be avoided in the binary parallel adder with the help of look ahead carry generator .............................................................................................................................
A full adder has a sum bit and a carry bit. A half adder just has a sum bit.
Carry select adder is used to select the carry during addition of two numbers. If those numbers are of 64 bits, then we call it as a 64 bit carry select adder.
A "half adder" circuit computes the resulting bit and carry bit from adding two bits together, assuming there is no carry (using an "exclusive-or" and an "and" operation, respectively). This is sufficient for the lowest-order bit, only; the remaining bit positions require a "full-adder" circuit to compute the result and carry from three inputs at each successive bit position (i.e. the two operands and the carry-in from the previous bit position).
half adder for addend and augend bits, generates partial sum and first partial carry bitshalf adder for partial sum and carry in bits, generates sum and second partial carry bitsgate to combine first and second partial carry bits, generates carry out bitdelay line or flipflop to feed a delayed version of the carry out bit back to the carry in bit
A half adder has 2 inputs and 2 outputs, these are usually called something like: Ain, Bin, Sout, Cout.A full adder has 3 inputs and 2 outputs, these are usually called something like: Ain, Bin, Cin, Sout, Cout.A & B are the 2 bits to be added, C is the carry bit, and S is the sum bit. A half adder cannot propagate carry as it has no carry input, a full adder canpropagate carry. A full adder can be built from 2 half adders.
The circuit which adds two single bit binary numbers and produce a sum and carry is a half adder circuit.
Full adder circuit:Full adder reduces circuit complexibility. It can be used to construct a ripple carry counter to add an n-bit number. Thus it is used in the ALU also. It is used in Processor chip like Snapdragon, Exynous or Intel pentium for CPU part . Which consists of ALU (Arithmetic Block unit) . This Block is used to make operations like Add, subtract, Multiply etcA full adder adds binary numbers and accounts for values carried in as well as out. A one-bit full adder adds three one-bit numbers, often written as A, B, and Cin; A and B are the operands, and Cin is a bit carried in from the previous less significant stage.The full adder is usually a component in a cascade of adders, which add 8, 16, 32, etc. bit binary numbers.
The 2-bit adder has two input lines and two output lines.The two input lines are the two bits to be added, call them "Bit-A" and "Bit-B".The two output lines are "sum" and "carry".Here are the states of the "sum" and "carry" outputs, for every combination of inputs "Bit-A" and "Bit-B":Bit-A . . . Bit-B . . . Sum . . . Carry0 . . . . . . . . 0 . . . . . . 0 . . . . . . 00 . . . . . . . . 1 . . . . . . 1 . . . . . . 01 . . . . . . . . 0 . . . . . . 1 . . . . . . 01 . . . . . . . . 1 . . . . . . 0 . . . . . . 1The Boolean functions for the two output lines are:SUM = [ (Bit-A) XOR (Bit-B) ]CARRY = [ (Bit-A) AND (Bit-B) ](Actually, I think the "adder" only has one output line, called "sum"; if it also has the "carry" output,then it's called a "full adder". To me, a full adder is a snake plus a dead frog.)
A full adder takes two inputs plus carry in and produces one output plus carry out. You need four full adders to add two 4 bit words. (No half adders required.)Or: for the lowest bit you can use a half-adder (no input carry).
10 ANd and 4 Or gate..
There are five flip-flops in a five-bit ripple counter.