# Recent questions tagged adder 1 vote
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How many inputs are required in Full Adder Circuit? $2$ $3$ More than two inputs None of the above
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It is necessary to design a decimal Adder for two digits represented in Excess-3 code. Show that the correction after adding the two digits with a four-bit binary adder is as follows. The output carry is equal to the carry from the binary adder. If the Output carry is 1 ... add 0011. if the output carry is 0 then add 1101. construct a four-bit decimal adder using two 4-bit adders and an inverter..
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Construct a 4-digit BCD adder-subtractor using 4 BCD adders. Use the Block diagram for each component, showing only inputs and outputs.
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How many Unused Combinations are there in BCD adder?
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Derive the two-level Boolean expression for the output carry $C _5$ shown in the look-ahead carry generator of the figure
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Assume that the EXCLUSIVE-OR gate has a propagation delay of 20ns and that the AND and OR gates have a Propagation delay of 10ns. What is the total Propagation delay time in the four-bit adder of the figure given below?
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(a) Redefine the carry propagate and carry generate as follows: $P _i = A _i + B _ i$ $G _i = A _iB _i$ Show that the output carry and output sum of a full adder becomes $C _i{+1} = (C _i'G _i + P _i')' = G _i + P _iC _i$ ... draw the two level look ahead circuit for this IC. [Hint: use the equation substitution method and AND-OR-INVERT funtion given in part (a) for $C _{i+1}$
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Using the AND-OR-Invert implementation procedure, show that the output carry in full adder can be expressed as $C _{i+1} = G _i + P _iC _i = (G _i'P _i + G _i'C _i')'$ IC type 74182 is a look-ahead carry generator MSI circuits that generate the carries with AND-OR ... -ahead carries $C _2 C _3 and C _4$ in this IC (HINT: Use the equation substitution method to derive carries in terms of $C _1'$).
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The adder-subtractor circuit of figure has the following values for mode input M and data inputs A and B. In each case, determine the values of the outputs: $S _ 4 S _3 S _2 S _1$ and $C _5$. M A B 0 0111 0110 0 1000 1001 1 0101 1000 1 0000 1010
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The adder-subtractor of the figure is used to subtract the following unsigned 4-bit number: 0110 – 1001(6 – 9) What are the binary values in the nine inputs of the circuit $?$ what are the binary values of the five outputs of the circuit$?$ Explain How the output is related to the operation of 6 – 9.
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Construct a BCD-to-Excess-3-code converter with a 4-bit adder.remember that the Excess-3 code digits obtained by adding 3 to the corresponding BCD Digit. what must be done to change the circuit to an excess-3-to-BCD-code converter
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Construct a 16-bit parallel adder with four MSI circuits, each containing a four-bit parallel adder. Use a block diagram with 9 inputs and five outputs for each 4-bit adder. Show how the carries are connected between the MSI circuits.
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Let $S(x,y,z)$ and $C(x,y,z)$ represents the Sum & Carry function of a full adder circuit. Which of the following options best represents $S(x,y,z)$ and $C(x,y,z)$ respectively? $x \oplus y \oplus z, y( x \oplus z)+xy$ $x \oplus y \oplus z, y(x+y+z)$ $x \odot y \odot z, z(x+y)+xy$ $\text{None of these}$
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x and y are two n bit numbers. these numbers are added by n bit carry look ahead adder which uses k logic levels. if the average gate delay of carry look ahead adder is d then what will be the maximum Delay of carry look ahead adder circuit? N2 Kd Nkd Nd
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Suppose we are using 4-bit carry lookahead adder modules to build a 64- bit adder with two-level carry lookahead, with ripple carry between the modules. If the delay of a basic gate (AND, OR, NOT) is 2 nanoseconds, the worst-case delay of the 64-bit adder will be ……….. nanoseconds.
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$1)$3-bit ripple adder, which adds two 3-bit numbers, is designed using AND, OR, NOT, NAND, NOR gates only. Assuming that all the inputs are available in both complemented and uncomplemented forms and the delay of each gate is one time unit, what is the ... in both complemented and uncomplemented forms and the delay of each gate is one time unit, what is the overall propagation delay of the adder?
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A full adder circuit takes 20 ns to generate the carry-out bit and 40 ns for the sum bit. When 4, 1 bit full adders are cascaded, the maximum rate of additions per second will be $\text{____} \times 10^6$sec. Usual Solution given The answer ... really calculate the total time taken to perform one round of four bit addition. Right? (Similar old question: https://gateoverflow.in/83500/digitals)
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How to check whether there is overflow in n-bit parallel adder?
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A $4 \hspace{0.1cm} bit$ carry lookahead adder which add two $4$ $bit$ number is designed using $AND ,OR,NOT,NAND,NOR$ gates only.Assuming that all the inputs are available in both complemented and uncomplemented form and the delay of each gate is one time ... doubt is if we take same $4$ $bit$ number instead of lookahead adder if we take parallel adder what will be overall propagation delay??
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