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Buffer could smooth the output, but why? The CMOS resistive inverters can act like a buffer smoothing out the output, if you do analysis on the circuit you will find the noise-margins for the input/output help cancel the perturbed noise from external influences. Consider the following circuit : Ring oscillator. The output from various inverters is being ...


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A CMOS buffer can also act as a level shifter. For example, when you have a sine wave with 400mV Vpp, and you want that sine wave to be a square wave swinging from rail-rail (from Vdd to Gnd), you can have a output buffer. Also, buffers are used as delay elements in logic circuits (for example reset), where you want an operation to happen after some time. ...


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Like others have already said (I'll just be a little more elaborate), unused CMOS input pins must never be unconnected, because they tend to float towards the dangerous region which is in the middle between VDD and GND. The input pin invariably is connected to another complementary MOS pair's gates, and the process parameters are often optimized for ...


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For CMOS, tie the inputs high or low. Do not leave them floating as then they will be in an undefined state and susceptible to external influences and can cause high current consumption or oscillation. It shouldn't make any appreciable difference whether you tie them high or low for a standard logic gate, so long as they are tied somewhere. For TTL, tie ...


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Usually you want to connect unused logic gate inputs to either VSS or VDD. In your case, this is exactly what you want to do, and since it's an inverter the choice here doesn't really matter. The documentation you have does provide this info (figure 17, Page 3-182).


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No, there are no parallel outputs on this chip. As you can see from the truth table below, when Parallel/Serial in is low a rising clock edge shifts data in from the serial input. When it is high, a rising clock edge loads from the parallel inputs. The only way you can get data out is from Q8, Q7 or Q6.


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This seems to be the standard textbook definition of VIH and VIL. Using a slope of -1 as the limit makes more sense if you think of inverters as amplifiers and remember that the input will have some noise: simulate this circuit – Schematic created using CircuitLab Going back to your graph, if the input voltage is between VIH and VIL, any noise ...


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I also see no specific significance in the points having a slope of -1, The most important point of this transfer curve is the point "VM" where input voltage=output voltage. This property of the CMOS transfer curve is used to bias the CMOS unit and to use it as a "linear" amplifier because this point - more or less - is in the middle of the Quasi-linear part ...


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The "slope=1" comment indicates that the diagonal line shows the point where Vin=Vout. If one has two inverters in a back-to-back configuration to form a latching circuit (to change the latched state, use stronger transistors to overpower the latching transistors), both inverters could sit at that precise voltage indefinitely. If one inverter's input was a ...


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The two leftmost transistors forms a simple not gate, but it is powered only when \$V_{x1}\$ is high. Luckily enough the passgate on the right is turned on when \$V_{x1}\$ is low instead, and directly connects the \$V_{x2}\$ input to the output. To sum it up: if \$V_{x1}\$ is high the output is NOT \$V_{x2}\$ if \$V_{x1}\$ is low the output is \$V_{x2}\$ ...


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"But we know that for input voltage 0 , PMOS will allow current flow and for input voltage VDD or logic value 1 , NMOS will allow current flow." That is not true in general, it holds only when the NMOS source is at 0 and the PMOS source is at 1, which is not (always) the case in your circuit.


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Imagine a load resistor (say 10K) from output to Vdd, and make X_1 and X_2 low. Ideally, output should be 0.0V. You can figure out what it is (not 0V). Now imagine a 10K load resistor from output to GND and make X_1 low and X_2 high. Ideally, output should be Vdd. You can figure out what it is (not Vdd). simulate this circuit – Schematic ...


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Intel 1101 256 bit SRAM probably had over 1K transistors. July 1969. They had an even early product- a bipolar SRAM, but bipolar SRAMs tend to use mutant BJTs with multiple emitters rather than multiple transistors so I doubt it hit the 1K milestone. There may have been others- prototpes, those aimed at military applications or in labs that were earlier. ...


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Based on the datamath webpage there were ICs around with more than 1000 transistors as early as 1967 used in TIs calculators prototypes. But it's not clear if this is a single chip or all three had together 1000 transistors and the exact chip is not mentioned. I've done some further research on the CalTech prototype. There is a patent available: Patent ...


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All mobile style cameras I came across used one of any of the three common Mobile Industry Processor Interface (MIPI) connectors. The one shown above is an FFC/FPC connector style. LVDS FFC. Board to Board connector. Both LVDS FFC and FFC/FPC look almost the same, while the BtB connector is different. The connector above is a 30-pin FFC/FPC 0.5mm ...


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HCMOS (74HC) is still very popular these days due to its wide voltage range and the fact that it still has through-hole packages, but LVC (74LVC) is useful for its lower bottom supply limit, 5V tolerance regardless of supply, partial power-down capability, reduced footprint packages, and reduced gate count devices (e.g. 74LVC2G00).


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The precise method depends on the particular spice engine. Most have something called a subciruit or package definition that would let your create the component as a schematic. Many also have the ability to define the behavior of an element programmatically. By entering a formula or script, relating the various values. There are many different levels of ...


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The design of the sensor and the interface really. Some are a parallel interface and could be 8,10,12 bit etc. It might include hsync and vsync or they might use embedded sync codes. Or it could be a serial interface and have only on lane or four or eight. The configuration interface could be spi or i2c. One might have more powers and grounds than ...



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