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25 votes

How is 10G Ethernet physically possible?

Chasing this answer down took a few different links, but it appears to boil down to this: 1. 4 differential pairs (8 wires total, but only 4 lanes). 2. 800 Mega Symbols a second. 3. Using PAM16, 16 ...
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  • 12.4k
24 votes
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Why is NAND gate preferred over NOR gate in industry?

1. NAND offers less delay. As you were saying, the equation for delay is $$Delay = t(gh+p)$$ But the logical effort \$g\$ for NAND is less than that of NOR. Consider the figure showing 2 input CMOS ...
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  • 8,137
22 votes
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12 hours delay with ATmega16A

I felt the need to give a non-blocking solution to the problem especially because we are talking about twelve hours of delay here. The util/delay.h library and its _delay_ms() and _delay_us() ...
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22 votes

Embedded C - Most elegant way to insert a delay

The context of this inline no-dependency delay is missing here. But I'm assuming you need a short delay during initialization or other part of the code where it is allowed to be blocking. Your ...
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  • 20.4k
16 votes
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Why is propagation delay a function of supply voltage?

I didn't really buy this argument. All else being equal, simply increasing the supply voltage should not increase the small-signal gain, which is out of scope anyways since the 'amplifier' is being ...
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15 votes

How is 10G Ethernet physically possible?

10G ethernet (as described by other answers) does not do signal transitions at 10 GHz, it uses multiple level encoding spread across 4 pairs to achieve 10 Gb/s. However, 10+ gigabit serial ...
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  • 2,389
14 votes

Rocket launcher circuit design

Having used commercial circuits and built a few myself... The standard model rocket igniter takes a fairly hefty current to work. In the olden days, an incandescent bulb was placed ACROSS the launch ...
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  • 5,504
12 votes

Embedded C - Most elegant way to insert a delay

Use a timer if you have one available. The SysTick is very simple to configure, with documentation in the Cortex M4 User guide (or M0 if you're on the M0 part). Increment a number in its interrupt, ...
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  • 4,469
11 votes
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PIC MCU: Software or hardware delay?

You need to go to the bank (which is just around the corner) and do your laundry. Going to laundry requires you to wait for the washer to finish, and then wait for the the dryer to finish. How would ...
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  • 11.5k
11 votes

Alternatives to RC circuit for simple variable delay up to 2 minutes

Depending on how you measure "simple", a small microcontroller is a good answer. Even the tiny PIC 10F200 can do this easily, and comes in a SOT-23 package. That's the same package single ...
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10 votes
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PIC Microcontroller - __delay_ms() no effect

while(1) { LATAbits.LATA5 = 1; //set pin as high __delay_ms(1000); //delay of 1second LATAbits.LATA5 = 0; //set pin as low } You don't let the LED stay ...
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10 votes
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Delaying a TTL signal

The Analog Devices / Linear Technology LT6993-1 (see circuit below) is a positive edge triggered pulse generator that has a resistor-programmable clock frequency and a resistor programmable divider ...
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  • 5,362
10 votes

Embedded C - Most elegant way to insert a delay

Not to detract from other answers here, but exactly what length delay do you need? Some datasheets mention nanoseconds; others microseconds; and still others milliseconds. Nanosecond delays are ...
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  • 1,423
9 votes
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Rocket launcher circuit design

simulate this circuit – Schematic created using CircuitLab Figure 1. Power-on indicator and buzzer additions. Simply add them in parallel as shown. BTW, congratulations on an excellent first ...
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  • 159k
9 votes

Minimizing signal delay when debouncing

The best way to handle this is to debounce the signal in software with your microcontroller. This is cheap, simple, and gives you maximum versatility in terms of your debounce algorithm. Here's an ...
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  • 4,695
8 votes
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Is this a correct way to have a 1 second delay?

Repeat loops are only really any good for "rough" timing and for short periods. There are many factors that can effect just how long your loop takes: Clock frequency accuracy. 4 million clock ...
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8 votes
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How do signal reflections work?

First, it's not really right to say that positive charges are holes in regular (not semi-conductor) metals. However, that's not the point here. You are OK thru the fourth diagram, but the 5th one is ...
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8 votes
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Arduino analogread: neighbor pin noise on ADC even with big delay

When you do analogRead internal capacitance of the MEGA 2560 are connected to the sensor and must be charge to the right voltage. Because your sensor uses a 220k pulldown your sensor has a large ...
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  • 321
8 votes

MOSFET Drivers to decrease turn on/off times

No. The datasheet tells you what the bare part can do, already assuming very fast gate transistions. The test conditions are usually listed in the datasheet. Read it.
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8 votes

How to create a 100ms delay between button pressed and line grounded?

Here is the circuit: The rest is firmware. The passive pullup on the GP3 pin is enabled. The pin therefore goes low when the button is pressed and high when not. The firmware debounces this and ...
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8 votes

Delaying a TTL signal

Custom Silicon Solutions makes the CSS555C, which is a 555 timer married to a wide counter. It allows you to count multiple timer cycles to use reasonably sized resistors to generate really long ...
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  • 5,362
8 votes
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Difficulty understanding group delay concept

(1) Let us start with the PHASE DELAY: The response of a linear two-port to a sinusoidal excitation is an output signal with the same frequency w but with a phase delay \$ \phi \$: \$ V_{out}=V_{max} ...
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  • 22.5k
8 votes

How to use libraries with delays inside within a time critical STM32 HAL application?

You can implement an RTOS and replace the HAL_Delay for the equivalent Thread_Sleep function available. But the library doesn't look very complicated, you can probably pick any of the options and do ...
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  • 20.4k
8 votes

My capacitor does not do what I expect it to do

My guess is that your capacitor has the wrong (too small) value, or you connected a polarized capacitor with reversed polarity. It is also possible that the base resistor (33k) actually has a much ...
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8 votes

My capacitor does not do what I expect it to do

I replaced the capacitor with another one (smaller cause that’s all I had) and it’s working so I guess my previous cap was defect.. Thanks a lot to all of you who took some time to help me
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  • 327
7 votes
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Software delay vs hardware timers

By hardware delays I meant 'Timers'. The advantage of using timers to realize a delay is that they provide a way to allow async counting. Using a "Software delay" you force the controller to put all ...
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  • 9,680
7 votes

Can a tank circuit store energy for a simple AC system?

Yes, your analisys is correct and the tank does essentially store AC. With a theoretical ideal inductor and capacitor, the tank would continue producing the same AC voltage when the switch is opened ...
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7 votes

How much does an op-amp delay?

Using an LTspice simulation with 100 MHz 0.5 V peak sine wave input and the Figure 36 unity gain buffer (+/-5 V supplies), and a 20 pF load, I get about 130 ps. You can see ...
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7 votes
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How to introduce delay to a signal

simulate this circuit – Schematic created using CircuitLab There is a tolerance on Vt+ and Vt- that shifts withtemperature that will make the delays asymmetric. Also if the waveform is not ...
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7 votes
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Does using a software delay() function have greater power consumption than using a System Timer interrupt?

Being curious myself I've made some simple measurements on a 32L152CDISCOVERY board. My test program consists of 4 tests, each displaying the elapsed seconds on the LCD. The difference between the ...
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