# Tag Info

13

Interestingly, none of the other answers tell you the main purpose of this inverter. They are all correct : this is a high impedance state. And as you quote in the question, this device needs a pull-up resistor to work. So why use a gate that needs an extra component? Because it's a way of sharing signals, of connecting several signals (possibly in ...

11

It represents a high impedance (Z) output state. The output will (ideally) neither sink nor source current, nor can it act as a voltage source.

7

You need to re-think your approach to Verilog. Being able to say c <= a + b; (adder) or i <= i + 1; (counter) on signals that can have arbitrary bit widths is much more concise and less error-prone than wiring up 4-bit chunks of 74xx logic. Let the synthesis tool take care of all the low-level details for you!

5

Z = high impedance state. An "open collector output" is just that - the output is a transistor collector pin. NPN type, more specifically, with the emitter tied to ground. So that collector only has two states: Signal feeding it's base = off, transistor in cutoff, collector = high impedance. Signal feeding it's base = on, transistor saturated, collector = ...

4

I suggest you to read the Hennessy & Patterson book on computer architecture "Computer Organization and Design: the Hardware/Software Interface". It is widely use in bachelor courses on computer architecture around the world. It is well written and easy to follow. Throughout the book the authors use a MIPS pipeline to explain the concepts that they ...

4

If driving reasonable inputs, move the output BEFORE (to the left of) the resistor in your Circuit 2 and it should work fine. If driving unreasonable inputs, you'll need a buffer. Use a resistor as large as you can get away with (experiment) and still see the LED light up to minimize load on the output from the LED. Many modern LEDs are quite visible with a ...

3

According to the paper found by @lustful-rat, T0-C is not a method for encoding binary words individually, but rather a method of encoding sequences of binary words. It is used in situations in which the sequences frequently contain groups of values that are a fixed offset from each other, such as stepping through a memory array by bytes or words. The ...

3

When you set out to make something that can support differential or single ended connections from the encoder why not try what I have done on a number of projects. Before delving into that let me clarify for you that differential encoders do not output voltage swings that go above and below GND. A single A+ or B+ or A- or B- will always swing from GND to ...

3

In parallel to the led + resistor. Optional Resistor to keep the GPIO within it's recommended current limit. Adjust values as needed. Logic level, high-impedence inputs could be connected directly without a resistor. simulate this circuit – Schematic created using CircuitLab

3

Maybe you can reverse engineer it, but it would be far easier to get a real datasheet. Whoever you buy these things from should be able to supply you with the relevant technical specs. If not, don't buy it. I took a quick look at the web site for the LED strip, and it seemed there was some source code there. If the source code is well written, then it ...

3

Yes this can be easily by considering the following picture simulate this circuit – Schematic created using CircuitLab Here in the above diagram,this D flipflop works when rising edge of clock is detected.On power ON the D will be in OFF and hence Q also OFF.As told early,the flipflop activates when +ve edge is detected.When rising edge is ...

3

As equations. $\overline{ABC} = \overline{(AB)C} = \overline{\overline{\bar A+\bar B}\cdot C}$

2

Yes. Though it is probably a little easier to make a fixed /5 divider, and then one that's selectable /6 or /7. Do you really want to make it from flip flops? Perhaps for the exercise, or you only have a box of HC74s? Because you can't make it purely from flip flops, you will need a few extra gates to make them recycle at 5, 6 or 7 counts. It's somewhat ...

2

In Brief Z mean "High Impedance State " In Deep, The inverter which you are seeing is tri-state inverter. High - Output Goes to 5V or depends on Vcc Low -0v High Impedance State- Consider as open circuit. For Better understanding consider this image(This is not inverter for understanding i added tri-state buffer which is also in same concept) When ...

2

D, JK or T flip flops can all be configured such that they divide by 2. SR flip-flops, by themselves, can not be wired to toggle that way. So they are not applicable. There are really only two types of counters you can build; a ripple counter, which divides by 2$^N$ using N flip-flops, and a ring counter, which divides by N using N flip-flops. The ...

2

simulate this circuit – Schematic created using CircuitLab

2

EDIT 3 : It was pointed out by commentors that this is not a true SPI. After looking further, I can see this information, which I missed in original : The strips basically implement a large shift register, like SPI, but with a small trick to allow use of only 2 signals – data and clock, without a separate reset or latch signal. Each LPD8806 ...

2

Your question is really too broad to answer. Our formal flow is the same as far as steps, but the outcomes are very different. I do both analog and digital design, and they are very different because your constraints are very different. Also, your goal is fundamentally different things. For instance, in an analog design I spend most of my time trying to ...

2

As has been indicated, this is not a good circuit, but I'll try until I get tired. Let's start with function. Apparently you want to do the following: 1) Run each battery through a difference amplifier to produce a (more or less) 3.7 volt level. 2) compare each level to 3.3 volts with a comparator 3) if any cell in a 4-call pack is low, turn on an LED ...

2

I'd suggest a more general approach (without counters) that needs some more gates but is much easier to understand and to debug and it can be adapted for more complex patterns. Drawn as classical logic gates: EDIT1: If you absolutely want (have) to use counters: one counter that increments with each 0 at the input. another counter that increments with ...

1

That circuit will not work, everything is wrong with it. especially the first column. in the first column comparators don't work like that, they they output high or low depending on only which of the two inputs has the higher voltage, they do not convert the difference to a voltage.

1

Get a pencil, get a paper. Write down all of the combinations of p and t then calculate w by hand. I'll do one for you... p=101 t=11 {w=(101+11-1)/11} => {w=(5+3-1)/3} => w=7/3=2.333 = 0b10.0101... Now do this for all possible inputs You never specified what kind of signal you need to output so I'll let you think about that. Then populate a table with ...

1

If you really want to take your hands of the keyboard often, then quartus has a symbolic editor with gates already made. Video Example. I'm sure some of the other synthesis tools have symbolic editors like this but it is so much easier to code it in with verilog or vhdl.

1

What, two conflicting pieces of advice are not enough? Let me see if I can contradict both of them at the same time. Well, not really. Neither one is exactly wrong. In principle, I'd say that converting to digital close to the sensor is the cleanest solution, but it requires that you have a place to put some circuitry there. If that is feasible, then ...

1

The 741 can't accept an input that's too close to the negative rail. The data sheet says the input range is +/- 13V when the power supply is +/- 15V. Not sure about when the negative power supply is 0V but I doubt it will work the way you expect with a 0V input. Similar story on the output side. That would explain the strange numbers you're getting below ...

1

If I were doing a silicon implementation, I would use an XOR because of the symmetric properties. Symmetric circuits us much less power because the stack size is the same that does a few useful things: 1) greater effective serial resistance when "off" due to the "stack of 2", 2) better matched channels because DIBL is the same on pull up and pull down ...

1

The K-map simplification seems to be wrong.The k -map simplification for A is A=x' and everything is right.For 0,just tie the input to ground

1

BBB run on Sitara AM335x which already has the interface for 3 encoders, it called eQEP. The pins are probably used as GPIOs, what you would need is to locate pins of your board, then search for suitable linux driver that can use/setup those GPIOs as eQEP, then you don't need an interrupt - this method is deprecated, it was used with MCUs without a time ...

1

A circuit that toggles the output for the rising edge of input is a frequency divide-by-2 system. JK flipflop in toggle mode (J=K=1) and T flipflop (with T=1) can readily implement this circuit. But all we have is a DFF. A positive edge triggered DFF captures the input(Data input) at rising edge of clock and this captured value is given as output. So if we ...

1

Not directly to 1.8V, but through a pull-up resistor of about 10K.

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