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2

This kind of intermittent failure can be a timing problem, but it can be a power supply problem. Since the latter is easier to debug, why not start there? If you did connect all the GND/VCC pins correctly I'll designate the HT7733 regulator as a suspect, since it's pretty much the only different part between the board that work and the one that doesn't. Well,...


1

Z = B’C’D + BC’D + C’D’ + CD’(B + A’B’)


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That board you linked is an I2C level shifter. I2C buses all have pullup resistors. Often in the low kiloOhms range. I suspect the pullup resistors are simply overwhelming the sensor trying to pull down to ground. Good luck.


1

when we connect it to the +5V supply or E, we can get 0 or 1 as an output. Connecting it to E makes it work like it is a two-input NAND gate. I know I have to choose one of them but which one. You could do it either way and the logic would work the same. So why choose one over the other? With 2 inputs connected together the signal loading is increased. ...


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The truth table is only true when there is power to the device. Without power, a NOR gate is a NON-gate, or NOT-A-gate.


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An analog circuit is not intrinsically more susceptible to noise than a digital circuit, because a digital circuit is made up of analog devices. Noise is a signal that interferes with the signal of interest. The difference in analog circuits and digital circuits is the kind of noise that can be safely tolerated. In a digital circuit, the important parameter ...


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It's almost never a good practice to connect the two MCUs' RX-TX pairs directly for relatively long-range (e.g. >2m) asynchronous serial communication. The possible problems are mostly solved by RS-485. RS-485 has a differential line (consisting of A and B lines) for relatively long-range asynchronous serial communication. But your MCU does not have the ...


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That part in itself converts single-ended transmit and receive signals to a differential, higher current bidirectional signal. This is part of the RS485 spec (and others) to improve the effective distance the signal can be sent, and reduce the number of pairs. What this part does not implement is the serial conversion itself. This requires some form of ...


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Assuming I am reading your notation properly, P and Q are the function inputs and R is the output. For the q projection gate it looks like P is irrelevant and R = Q. That is to say, for any value of Q, I can change P to any value and it doesn't affect the result. for the p projection gate it looks like Q is irrelevant and R = P. That is to say, for any ...


1

A sequential computer can emulate a parallel computer. All it needs to do is to compute the "next step" state from the current state without changing the current state in the process of computation. Like, for instance, Conways Game of Life is clearly a parallel machine, but can be easily simulated, and many times has been done. The array of the &...


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You have not only short-circuited the gate inputs and outputs but also the power supply. In my opinion, a little practical experience would stand you in good stead. To start with, you would do well to get hands-on experience with gate logic by using switches and lamps. That would also help you understand how to wire up a circuit. Later you could try your ...


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Problems: 1 and 2. Short circuits between V+ and V-. 3, 4, 5 & 6. Short circuits between inverter inputs and outputs. 7 and 8. LEDs with no current limiting resistors. It looks like you copied the outline of a hex-inverter chip into your schematic. (That was wrong.) Tip for future questions: Turn off the grid before taking a screengrab. Screengrab on ...


1

Indeed, the ordering of indices doesn't matter in that $$ΠM(1,3,6) = Σm(1,3,6)$$ holds both for the straight and for the reversed orders of indexing, providing these are identical on the left and on the right of the equality sign. The value of $$f(x_1, x_2, x_3)$$ does depend on the index ordering.


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Each input goes to a edge detector which outputs a pulse. It needs to detect either edge. Like this one: dual edge detector Those outputs are then ORed together (4 input OR gate) to a D-Flop clock input. Connect \$\overline{Q}\$ output to input \$D\$


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All other things being equal, digital signals only need to resolve two levels: a valid ‘0’ or ‘1’. The receiving end sets these thresholds and snaps to one of the valid levels, and so can be designed to reject a considerable amount of noise on the line. Analog signals are continuous. The entire range of the signal swing contains information. Any added noise ...


3

It all depends on the application that you are talking about, but generally the reason is because a digital circuit is either on or off. So lets say that in order to measure a digital high, the minimum threshold may be around 2-2.7v for 5v logic. And to register a low, it may only need to be as low as 0.8v. So any small amount of noise is generally not going ...


2

Headphone drivers (Class D or otherwise) for portables are limited in swing by the power supply. They do however use a few tricks to achieve greater loudness: (more expensive ones) full H-bridge drive (cheaper ones) common-mode bass drive To answer your voltage-conversion question, Class-D drivers use a kind of PWM-to-analog conversion that basically ...


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A Diodes Inc Class D is rated for 8R to about 1.5W @ 5.5V max so with 32R it may be about 1/4 of this. If you have a larger supply then it must be reduced It also operates down to 2.8V @ 0.5W @ 0.5% THD. Or 0.1W @ 0.1% PAM8302A. $5.71 for the PCB Adafruit Another example which shows power vs THD vs load R https://cdn-shop.adafruit.com/product-files/3006/...


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Why not use a level-shifter, a part designed to do this. You need to find one that can translate up to 12V, a CD4504 seems to fit. Of course, you will need a 12V supply.


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It is highly unlikely that it will be worth it to convert a MAX232 circuit to drive this PWM. MAX232 in general uses the supplied 5V to make +/- 7 volts with a charge pump, it might be possible to make it drive 0V and 12V, but it would require an external 12V supply, and while being within absolute maximum ratings, this kind of configuration is not shown in ...


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Most probably you reset the simulation, but you have no running clock. So the NORs get 0 on one of their inputs, and ERROR on the other, since their default output value is this. As long as this does not change, the NORs cannot output any other value, because 0 OR ERROR is still ERROR. Start the clock via the menu "Simulate" - "Ticks enabled&...


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I need to have addition be op code 010, which is what it is now, but I need subtraction to be op code 110 The output of the adder should split and go to both the '010' input and the '110' input. The op code value should also be used for additional logic gates that configure the adder for adding or subtracting.


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You need to provide a delay for the dflop, through the parameter td. The reason is that the state at the output and at the input coincide without any delay, and (quote from the manual, LTspice > Circuit Elements > A. Special Functions): The gates and Schmitt trigger devices supply no timestep information to the simulation engine by default. That is, ...


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The simplest thing is to just add the input number to itself. Doubling a number (multiplication by 2) is equivalent to a left shift in binary. In other words, select ADD as the ALU operation, and feed the input value to both inputs of the ALU. If you do add-with-carry, then the carry bit will automatically get shifted into the LSB. In either case, the carry-...


0

The time taken for a parallel divider to complete its operation is only due to the total delay of the gates in the combinational circuit. A serial divider takes many cycles to complete its operation. Hence the total delay is the product of the time taken to complete a cycle and the total number of cycles. For a given technology node the parallel divider ...


1

Excellent question, it's great you're curious about how things around you work! Unfortunately, as others have noted this is a huge topic; and the specific protocols you mentioned like Bluetooth and Wifi are complicated and the product of over a century of development stretching back to the telegraph (and probably further to smoke signals come to think of it)....


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You already know about amplitude and frequency modulation. In addition there are a number of other methods including phase modulation. Here are a few ... BFSK - Binary Frequency Shift Keying E-FSK - Enhanced-Frequency Shift Keying FSK/IM - Frequency Shift Keying/Intensity Modulation GFSK - Gaussian Frequency Shift Keying QASK - Quadrature Amplitude-Shift ...


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There are quite a few basic ways to do it. Important ones include: The earliest radio systems used pulse-width modulation on some carrier frequency (possibly just the natural resonant frequency of the antenna), broadcasting short and long pulses in the dot-dash code of Samuel Morse. This turns the carrier signal abruptly on and off, which causes problems in ...


2

If you want to know how 'A' from from keyboard via Bluetooth to your computer starting from 1s and 0s on an analogue wave, then it's far too complicated for any person to think about all at once. So we divide it into layers. Each layer uses the services of the layer below, and provides services for the layer above. This allows us to concentrate on just a few ...


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"Analog" as the opposite for "digital" is a remnant from the era when analog computers were common tools for solving engineering equations. Digital computers were too slow and the numerical calculation methods were too inaccurate. An electric, pneumatic, hydraulic or mechanical circuit which satisfied the same equation (=had an analogy) ...


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Traditionally a clock is edge triggered. A level-driven "causer of change" would tend to be an "asynchronous load" (if it accepts arbitrary data) or a "set" or "reset"/"clear" if it is both the cause of change and the resulting state. To understand the details of your particular part, please refer to its data ...


0

Using De Morgan's laws and this question and following answers which contain some simplification tables : A^B = A`B + AB` (AC ^ BD) + A = (AC)`(BD) + (AC)(BD)` +A = (A`+C`)(BD) + (AC)(B`+D`) + A = A`BD + C`BD + AB`C + ACD` + A = A(B`C + CD` + 1) + A`BD + C`BD = A + A`BD + C`BD = A + BD + C`BD = A + BD(C` + 1) = A + BD for learning purposes, if you want to ...


0

I designed in a 1x16 character VFD display into a product back in the early 1990s. Like this one it also came from Futaba. This was a 'bare' display with no driver chip as yours seems to be. Driving the display helps if you consider that it resembles a multi-anode thermionic valve (vacuum tube), actually a multi anode, multi grid directly heated cathode ...


1

When Q2 is on, V0 is off. For Q2 to be on, Q1 must be on. (pnp, negative base current) For Q1 to be on, H_BRIDGE_HI must be high. (npn, positive base current) When Q5 is on, V1 is off. For Q5 to be on, H_BRIDGE_LO must be high. (npn, negative base current) They're both inverting. Missing from this circuit is shoot trough prevention and dead time insertion. ...


1

Re: "I was wondering what relation is between memory (RAM, ROM) and PLD (ROM, PLA, PAL, CPLD, FPGA), and the other topics such as (synchronous) sequential circuits" These are all things that you might use to create (synchronous) sequential circuits. Re: "Are memory and PLD some examples or applications of (synchronous) sequential circuits"...


1

A PWM output will give you a PWM signal. It's operating frequency will be limited by the clock frequency and the divider options that the microcontroller features. If one of the available configurations suits your application then you can generate a continuous pulse train at that frequency with variable PWM. You haven't changed or invented anything new so ...


2

For example to act like an on-off signal by varying the duty cycle between 0 and 100%. Sure, a PWM that's on 100% of the time is just a "high" output. Same with 0% and "low". However, this sounds like something you ask in context of a microcontroller. I've yet to meet a microcontroller where you have a pin that you can connect to a PWM ...


1

Assuming a '6 nS signal' means a pulse of length 6 nS, and assuming that the 5 nS delay applies to both the high-going and low-going edges for the gate, then the 6 nS pulse emerges from the gate output as a 6 nS pulse, 5 nS after it went in. In general, gates tend to have different specifications for the tPHL and tPLH times (time for Propagation High to Low, ...


1

Look at the model. Yours (or the one shown in your figure) is TM-619H-2, it works on AC200-250Vac. However, the model TM-619H-4 works on 12Vdc:


0

Looks OK to me. It's designed to switch either an AC or DC load. In the case of DC up to 30V and 20A well able to handle your requirement.


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