Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Slide02 digital logic operations and functions

1,094 views

Published on

  • Be the first to comment

  • Be the first to like this

Slide02 digital logic operations and functions

  1. 1. 517212: Digital Logic Designบทที่ 2 - หนาที่และการทำงานของวงจรดิจิทัล 12 พฤศจิกายน 2555
  2. 2. ตัวปฏิบัติการพื้นฐานทางลอจิก ระบบดิจิทัลนั้นสรางจากพื้นฐานทางตรรกศาสตร จอรจ บูล (George Boole) นักคณิตศาสตรชาวอังกฤษไดสรางพีชคณิต เชิงตรรก (Boolean Algebra) ขึ้นมาในชวงทศวรรษที่ 19 ซึ่งภายหลังได นำมาประยุกตใชในการออกแบบและสรางระบบดิจิทัล ตัวปฏิบัติการเชิงตรรกที่ใชเปนพื้นฐานและควรทราบนั้นมีอยูเพียง 3 แบบ ไดแก NOT AND OR
  3. 3. NOTNegationOutput is the opposite of the input, that’s all.The symbol:Note: There is only one input and one output for this op!
  4. 4. ANDThe output will be HIGH only when all the inputs are HIGH.The symbol: Note: there may be more than two inputs.
  5. 5. ORThe output will be HIGH when one or more inputs are HIGH.The symbol:
  6. 6. Basic Logic Functions Roadmap to what we are going to learn: –Comparison function –Arithmetic functions –Code conversion function –Encoding function –Decoding function –Data selection function –Storage function –Counting function
  7. 7. ComparisonA basic comparator compares two quantities and indicates whether or not they are equal. –Think about conditional statement like if or things like that in programming.
  8. 8. Arithmetic Adder is the key-element circuit of binary arithmetic. – You can add (of course, it’s the adder). – You can subtract using adder with special treatment on input number. – You can multiply using adder with the help of other circuits. – You can also divide with series of circuits in conjunction of adder.
  9. 9. Code ConversionA code converter changes one form of coded information into another coded form, i.e.: –binary-to-BCD –binary-to-Gray code –etc.
  10. 10. Encoding and Decoding Encoder converts information, such as a decimal number or an alphabetic character, into some coded form. Decoder does the opposite.
  11. 11. Data Selection Multiplexer (MUX) – Switches digital data from several input lines on a single output line in a special time sequence. Demultiplexer (DEMUX) – Does the opposite.
  12. 12. Storage This function is required in most digital systems. Itcan memorize a bit of a group of bits and retain the information as long as necessary. – Flip-flops – Registers – etc
  13. 13. CountingCounting is one of the most important function in digital systems. –Think about the loop in programming, you cannot accomplish unless you have some sort of counter.To count, the counter must remember the present numbers  it can go to the next proper number in sequence.
  14. 14. Integrated Circuits (ICs)
  15. 15. Fixed-Function ICs http://www.bbc.co.uk/schools/gcsebitesize/ design/images/dt_chip.jpg http://www.dolphin.fr/corporate/announcements/ pressrelease/2002/images/dsair.jpg http://www.tiscali.co.uk/reference/encyclopaedia/ hutchinson/images/c01356.jpg
  16. 16. Complexity Classifications for Fixed-Function ICs Small-scale integration (SSI) – Up to 10 gate circuits Medium-scale integration (MSI) – 10-100 gate circuits Large-scale integration (LSI) – 100-10,000 gates Very large-scale integration (VLSI) – 10,000-100,000 gates Ultra large-scale integration (ULSI) – More than 100,000 gates
  17. 17. Programmable Logic PL devices can be programmed to perform specified logic functions using software. –Hardware Description Language (HDL)A design can be implemented faster and with less cost (small volume). Just remember the name: –Field Programmable Gate Array (FPGA) –Complex Programmable Logic Device (CPLD)
  18. 18. รูป title page http://4.bp.blogspot.com/_FdGFE8NBDgc/TAdzuXy9VEI/AAAAAAAAC_A/73pzDSvpgww/s1600/mains-frequency-monitor-circuit-diagram.jpg

×