Download presentation

Presentation is loading. Please wait.

Published byJasmine Tesh Modified over 2 years ago

1
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 1 Combinational Circuit – Arithmetic Circuit Parallel Adder Example: 4-bit adder

2
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 2 Combinational Circuit – Arithmetic Circuit Cascading Adder –Cascade four full adder –Classical method: 9 variable input needs 2 9 = 512 line of truth table Cascading method can be expanded to greater number. Example: 16-bit parallel adder

3
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 3 Combinational Circuit – Arithmetic Circuit Usage: Poling system (for 6 person) –Use full adder and parallel adder 4-bit (binary) –Each full adder can add 3 polls

4
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 4 Combinational Gates – Arithmetic Circuit Adder-Subtractor –Use two’s complement X-Y=X+(-Y) –Two’s complement for Y = invert each Y bit and add 1

5
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 5 Combinational Gates – Arithmetic Circuit BCD Adder –Classical method needs 29 lines in TT –As a replacement, we use binary adder with a little alteration

6
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 6 Combinational Gates – Arithmetic Circuit BCD Adder Strategy –Use 4-bit parallel adder to ad 2 BCD code –If answer <10, therefore it is correct (just leave it) –If answer ≥10, therefore some calibration is needed to get to correct C, S 8, S 4, S 2 and S 1. Repeat this strategy for other 4-bit parallel adder

7
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 7 Combinational Gates – Arithmetic Circuit When answer <10, therefore total BCD = total Binary, no calibration is needed When answer ≥10, therefore Calibration Total BCD = Total Binary + requirement for calibration C=K+Z 8.Z 4 + Z 8.Z 2

8
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 8 Combinational Gates – Arithmetic Circuit Comparator –Magnitude comparator: compare two value A and B to ensure if A>B, A=B or A**b3) therefore A>B –If (a3
{
"@context": "http://schema.org",
"@type": "ImageObject",
"contentUrl": "http://images.slideplayer.com/12/3378341/slides/slide_8.jpg",
"name": "MOHD.",
"description": "YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 8 Combinational Gates – Arithmetic Circuit Comparator –Magnitude comparator: compare two value A and B to ensure if A>B, A=B or A**

9
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 9 Combinational Gates – Arithmetic Circuit A3A3 A2A2 A1A1 A0A0 B2B2 B1B1 B0B0 B3B3 x3x3 x2x2 x1x1 x0x0 A 3 B 3 ’ A 3 ’B 3 (A**B) (A=B) A 3 ’B 3 + x 3 A 2 ’B 2 + x 3 x 2 A 1 ’B 1 + x 3 x 2 x 1 A 0 ’B 0 A 3 B 3 ’ + x 3 A 2 B 2 ’ + x 3 x 2 A 1 B 1 ’ + x 3 x 2 x 1 A 0 B 0 ’ x3x2x1x0x3x2x1x0
**

10
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 10 Combinational Circuit - Arithmetic Circuit Comparator

11
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 11 Combinational Circuit – MSI Circuit There are four useful MSI circuit –Decoder –Demultiplexer –Encoder –Multiplexer Block Diagram

12
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 12 Combinational Circuit – MSI Circuit DECODER Codes used for representing entity, e.g. your name is a code which represent yourself (entity) This code can be identified (or decoded) using a decoder: Provide code, identify entity Change binary information from n input line (maximum value for) 2 n output line Is known as line decoder n to m, or n:m or nxm decoder (m<=2 n ) Might be used to generate 2 n (or less) minterm for n input variable

13
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 13 Combinational Circuit – MSI Circuit DECODER Example: if code 00, 0, 10, 11is used to identify four bulbs, therefore we need 2-bit decoder This is 2x4 decoder which select output line based on the given 2 bit. Truth table

14
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 14 Combinational Circuit – MSI Circuit DECODER From the truth table, decoder circuit 2x4 is Notes: each output in 2 variable minterm expression (X’Y’, X’Y, XY’, XY)

15
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 15 Combinational Circuit – MSI Circuit DECODER Design of 3x8 decoder Usage? Conversion from binary to octal

16
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 16 Combinational Circuit – MSI Circuit DECODER In general: for n-bit code, decoder suppose to select up to 2 n line

17
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 17 Combinational Circuit – MSI Circuit DECODER – Function execution Boolean function in SOM for can be executed with decoder (to generate minterm) and OR gate (used for forming “sum”) Any combinational circuit with n input and m output can be done with n:2 n decoder and with m OR gate Good for circuit with a lot of output, and each function is express with several minterm

18
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 18 Combinational Circuit – MSI Circuit DECODER – Function execution Example: Full Adder

19
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 19 Combinational Circuit – MSI Circuit DECODER with Enable Most decoder has an enable signal, therefore it only active when enable, E=1 Truth table

20
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 20 Combinational Circuit – MSI Circuit DECODER with Enable In MSI, enable signal for decoder is zero enable, E’, therefore this device only active when enable E’=0

21
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 21 Combinational Circuit – MSI Circuit LARGE DECODER Large decoder can be built using small size decoder E.g. 3:8 decoder can be built using 2:4 (with 1 enable) as the following

22
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 22 Combinational Circuit – MSI Circuit LARGE DECODER E.g. 4:16 decoder can be built using two 3:8 decoder (with 1 enable) as the following. How can you build 4:16 decoder by using 2:4 decoder with enable?

23
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 23 Combinational Circuit – MSI Circuit ENCODER Encoder is the inversion of decoder. Several sets of input line, select one, it produce similar code for selected line Consist of 2 n (or less) input line and n output line Created from OR gate Example:

24
MOHD. YAMANI IDRIS/ NOORZAILY MOHAMED NOOR 24 Combinational Circuit – MSI Circuit Truth table

Similar presentations

Presentation is loading. Please wait....

OK

Combinational Circuit – Arithmetic Circuit

Combinational Circuit – Arithmetic Circuit

© 2017 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Ppt on total internal reflection critical angle Ppt on articles of association and memorandum Ppt on file system in operating system Ppt on protein energy malnutrition with its management Ppt on inhabiting other planets that could support Ppt on toyota production system Ppt on suspension type insulation tool Ppt on zener diodes Ppt on viruses and bacteria articles Ppt on modernization in indian railways