• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Logic gates

Extracts from this document...


Task 1 For each of the gates listed below, explain their operation showing appropriate gate symbols, truth tables and logic equations for the outputs in terms of the input variables. a) Two input OR gate Logic gates process signals which represent true or false. Normally the positive supply voltage +Vs represent true and 0V represents false. Other terms which are used for the true and false states are shown in the table on the right. It is best to be familiar with them all. The output Q is true if input A OR input B is true (or both of them are true): Q = A OR B An OR gate can have two or more inputs, its output is true if at least one input is true. Input A Input B Output Q 0 0 0 0 1 1 1 0 1 1 1 1 Traditional symbol IEC symbol Truth Table b) Two input AND gate The AND gate is a digital logic gate that implements logical conjunction - it behaves according to the truth table to the right. ...read more.


the NOR gate Z = A.B.C + A.B.C + A.B.C + A.B.C A B C Z 0 0 0 1 0 0 1 1 0 1 0 1 0 1 1 0 1 0 0 1 1 0 1 0 1 1 0 0 1 1 1 0 Task 5 For this task I was asked to produce a minimized circuit. I did this by using the karnaugh map below. BC A 00 01 11 10 0 1 1 1 1 1 The minimized equation for this circuit is: A.B + A.C + B.C I built this circuit, using the same equipment as previous, such as the logic probe etc. this circuit does the function as the original circuit, but only this time there are less components used. This has many benefits, as it makes the entire circuit cheaper to build, and the person building the circuit is less likely to make a mistake in the construction of it. Task 6 Compare and contrast, with reference to five characteristics the differences between the 2 types of logic family listed below. ...read more.


On the CMOS, the delay ranges from 95-40ns. The propagation delay time, is the time it takes to send the signal from the sender to the receiver. TTL would be the best suited for changing signal outputs quickly. The TTL supply current ranges from 11-33mA. CMOS ranges from 1-30A. the CMOS chip requires less amps to operate, so for it would be better suited for low power circuits. The TTL needs 4.75-5.25V, whilst CMOS chip requires between 3-15V. this means the CMOS chip would be the best for altering voltage. This makes CMOS the most useful. TTL can operate at a temperature range of 0-70C. The CMOS chip again beats this, because it has a superior temperature operating range of -40-+85C. CMOS wins this because it is best suited to large temperature changes. The high level output voltage on the TTL chip is 2.4v, whilst the CMOS has an output voltage, of 2 thirds that of the input voltage. E.g. if the input voltage is 5V, the output is 3.333V. In conclusion I feel that the CMOS chip is the superior chip for today's demands. The only area that CMOS is outperformed by TTL is the Propagation Delay Time. This means CMOS is a great chip. ?? ?? ?? ?? Gavin O'Hara ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Design and Technology section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Design and Technology essays

  1. Bedside table development evaluation

    This can not be tested at this stage, but looking at the design of the drawer the drawer should be able to open as easily after any amount of times, but the metals haft that allows drawer to rotate might be the first past of the design to wear.

  2. Devlopment evaluation of my bedside table.

    they are all hardwearing and durable so should last more than the expect 4-5 years of standard bedside tables. All materials used are able to be recycled and reused, I will include a word document making customers aware materials are recyclable and reusable All materials are reasonably lightweight and all

  1. Research in the uses of silicon

    In fact it is amazing how rare native silicon is with 25.7% of the Earth's crust being silicon. Silicon, binds strongly with oxygen and is nearly always found as silicon dioxide, SiO2 (quartz), or as a silicate (SiO4) Silicon has been found as a native mineral only in volcanic exhalations and as tiny inclusions in gold.

  2. It is important that Sarah is blind having access to speech and Braille output ...

    The disadvantage is that because they are technologies they will need maintenance and could malfunction, which could be very dangerous since Steven is quite dependant on them. It is very expensive, if it breaks, that would be a problem for her to buy, and she can not afford that much money.

  1. Describe the benefits of technological developments in equipment and facility design in two contrasting ...

    On the other hand the football has changed a lot more dramatically over the last 30 years with the balls changing to a synthetic material which makes it unbelievably light. Over the years there have been a lot my adaptations to the football than the tennis ball.

  2. The Characteristics and Development of RFID - Radio frequency identification.

    of supply chain and of inventory management with attendant cost savings; reduced labour costs; improvements in customer service; reductions in shrinkage; and clearer targeting of customers and tracking of their purchasing behavior. Initially supply chain applications appear to be the fastest growing RFID usage within retailing and the technology would

  1. Printed Circuit Boards.

    The next step to making a printed circuit board is to design the artwork of the printed circuit board. The artwork (or layout) is the pattern that is to be etched in the copper. The artwork can be produced in many ways also; the traditional and popular method is by

  2. The Differences and Assimilation of Chinese and American Diet

    that the American diet is better in the nutrition part than the Chinese diet because it consumes less carbohydrate uses less oil, American people eats more dairy products in their meal too. Comparing to Americans, I believe Chinese people are less concerned about exercising activities and their health problems.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work