Interview Question in digital logic |
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logic gates, digital logic gates, OR logic gate, AND logic gate, logic gate symbols, logic gate simulator, ttl logic gate, and or logic gate, basic logic gate, binary logic gate, nand gate, nor gate, not gate, circuit gate, logic transistor, inverter gate, logic multiplexer, xnor gate, combinational gate, delay gate, diagram gate, gate input, transmission gate, tutorial gate, using gate, xor gate
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digital circuit, digital circuit design, digital integrated circuit, digital circuit logic, digital electronic circuits, digital circuit simulation, digital clock circuits, digital circuit detective, digital circuit testing, adder digital circuit, digital vlsi circuits, digital inverter circuit, digital design, digital logic, digital level, digital cmos, logic circuit, digital ic, digital ttl, digital layout, digital schematic, gate circuit, tutorial circuit, digital inputs, digital switching, digital multiplexer, digital circuitry, digital vlsi
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I'm using a rectifier which uses a center tap transformer (which is rated at 6.3V, .45A), two 400PIV diodes forming a full tap rectifier, one inductor (a 35A toroid coil) and a 1000uF, 16V electrolytic capacitor, the latter two used to filter the current, all leading to a 7805 +5VDC voltage regulator Now my question is (and please focus on the question and not the overkill of my 12V power source), is there any reason why my 5VDC generator refuses to work with and digital logic, i.e. CMOS? What I mean by "refuses to work" is burns up the chips, but if I put a 1k ohm current-limiting resistor in front of the voltage-in of the IC (for example, pins 8 and 4 on a 555 timer) which would deliver 5mA (5V/1000ohm=.005A=5mA) the IC doesn't even function, and the voltage input at pin 8 leaves pin 3 the same or, if I've grounded pin 1, at about 1/10 the voltage. Any help would be greatly appreciated, and if anyone has any suggestions for a power source better suited for CMOS projects, I'm open.
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Tax, Title & License?
TTL can refer to:
* Time to live for computer data
* Transistor–transistor logic, a type of digital logic-gate circuits
* Through-the-lens measurements in photography
* Taiwan Tobacco and Liquor
* Total
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They are two different techniques for making digital logic components. These two are not the only digital logic technologies, although they are perhaps the most widely known. Other technologies include NMOS, ECL, and some others.
TTL stands for "transistor-transistor logic". It uses bipolar transistors. Bipolar transistors are constructed vertically into the surface of the semiconductor material (usually silicon). Each transistor has three regions that are in physical contact with one another. The regions are called emitter, base, and collector. All three regions are below the surface of the semiconductor.
CMOS stands for "complimentary metal oxide semiconductor". It uses MOS transistors. MOS transistors are constructed horizontally across the surface of the semiconductor materal. Each transistor has three regions, but they are not all in physical contact. The regions are called source, gate, and drain. The source and drain are below the surface, but the gate is constructed above the surface of the semiconductor material. The gate is separated from the semiconductor by a very thin layer of silicon dioxide (glass). Thus, the gate is electrically insulated from both the source and the drain. The gate exerts its effect on the device by means of its electric field, which can extend through the glass.
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TTL (Transistor-Transistor Logic) is a name for type of logic circuits which are constructed using the bipolar transistors.
In general the bipolar transistors such as the NPN and PNP transistors are current operated devices. In these types of transistors, when used for digital logic circuits, typically the input voltage is applied across the Base-Emitter junction. As a result of this a small base current is produced in that junction. This small base current is magnified by the transistor's current gain factor B(called Beta), resulting in a large amount of collector-emitter current. This is basiclly how a TTL switch works.
The TTL family of circuits are generally very fast, but this speed comes at the cost of higher power dissipation. Also, a typical TTL logic gate circuit requires multiple transistors and other passive components such as resistors. This results in lower number of gates that can be put on an IC built using TTL family.
The CMOS(Complimentary Metal Oxide Semiconductor) family of logic circuits are buit using Metal Oxide Semiconductor(MOS) Field Effect Transistors (FET). These types of transistors are voltage operated devices. A typical CMOS logic gate circuit can be constructed using as little as two MOSFET transistors (A CMOS Inverter) resulting in a much higher density of logic gates that can be put on an IC.
Also, CMOS gates use much much lower power to operate compared to the TTL gates because no resistors are required to build such circuits.
CMOS logic also allows much higher operating voltages compared to the TTL family.
One drawback of CMOS family is that they are slower than the TTL family, however these days this may no longer be true.
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Draw 16-input Multiplexer by using 4-to-1 Multiplexers
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Mathematical Logic
Probability
Set theory and algebra
combinatorics
graph theory
linear algebra
numerical methods
calculus
theory of computation
digital logic
computer organization and architecture
programming and data structures
algorithms
compiler design
operating system
databases
computer networks
in short i want to cover the GATE SYLLABUS for computer science and engineering
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it is requierd to do a 7segment driver to display an octal number on a 7 segment LED display..
and this function have 3 input and 4 output...
and i try to minimize the fuction as possible as i can but it still in the function 22 gates ....how can i reduce it more???
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it is requierd to do a 7segment driver to display an octal number on a 7 segment LED display..
and this function have 3 input and 4 output...
and i try to minimize the fuction as possible as i can but it still in the function 22 gates ....how can i reduce it more???
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What would be my final project for DLD(digital logic design)?
PLZ help me i am really tired to think about any project
My teacher taught us only basic gates AND OR NAND NOR OR with 74 IC series of 14pin he instruct us your project must contain at least 6 ICS full used.
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I'm in VLSI and I think I've forgotten how to do this..but I may have to on a test (designing Compound Gates using transistors..). So for example: Y = AB + C+D
Would the complement be
A(complement) + B(complement) *C(complement)*D(complement)
I know it's probably simple, but it's been a really long time since I've taken digital logic. Thanks
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Not enough information in your question. Input/output levels not specified.
The NOT gate or inverter is a digital logic gate that implements logical negation. A HIGH output (1) results if the input is LOW (0). If the input is HIGH (1), a LOW output (0) results.
Hope this helps. See the source link for additional info if needed. Cheers!
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reserve words in digital logic gates
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reserve words in digital logic gates
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This is the question for, who are studying or teaching digital logic design
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I am taking a digital logic class and we need to know how to use negative logic but they haven't done a very good job of teaching this so I am a little confused.
For example, given the following truth table (where F is output):
A | B | C | F |
-----------------
L | L | L | L |
L | L | H | L |
L | H | L | H |
L | H | H | H |
H | L | L | L |
H | L | H | L |
H | H | L | H |
H | H | H | H |
Describe the circuit in (a) positive logic and (b) negative logic.
I know for positive logic you would replace the Hs with 1s and Ls with 0s. Then F(A,B,C) would equal all terms (each term would be made up the variables equal to 1 in that row ANDed with the variables equal to 0 set to their NOT) corresponding to rows with output of 1 ORed together.
Now with negative logic I know the Hs would be replaced with 0s and the Ls would be replaced with 1s. I'm not sure how to proceed after this point.
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common Architecture of printers & digital logic of operation
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This is digital logic intro by the way. I know how to set the circuit but I don't know what we are supposed to be learning from this.
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what kind of jobs can i get if i concentrate on these areas...
1) digital logic/digital systems/networking
2) communications/digital signal processing
3) integrated circuit design and fabrication <-- i am interested in this one so if you could give a lot of detail on this field
4) analog electronics
can you give as much detail as possible. just want to see what i want to do for the rest of my life.
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