Questions tagged [timer]

Circuit to generate a signal at a specific time after a trigger event. The timing can be defined by an RC time constant, or by clock pulses from an oscillator.

One way to implement a timer is as a digital counter incremented on a fixed clock frequency, allowing for generation of periodic or non-periodic timed events. It is one of the most basic and common internal peripherals found on micro-controllers, and can be used for a wide range of tasks like interrupt generation, time measurement, PWM generation, etc.

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4 or 5 Time Constants to reach practical potential?

While I'm aware that a component can never "fully" charge or discharge to 100%, one textbook I'm using (Practical Electronics - 6th Edition, Sinclair, Dunton) says that we can assume a component has reached roughly its full practical potential after…
Tim Crossey
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Simple Metronome Circuit w/ Linear Pot Control

I'm trying to design a square wave oscillator to control an LED with a LINEAR frequency control range of ~0.017 Hz to ~17 Hz (1 BPM to 1000 BPM). EDIT Oli's excellent answer and circuit indeed make the duration between discharges linear wrt the…
squarewav
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General directions for a timer circuit which will not use microcontroller and which can measure several hours needed

Some background info first: In my country, price of electricity depends among other things on the time of the day when energy is used. Because of that, many people tend to turn on big energy consumers after midnight, when electricity is cheaper. One…
AndrejaKo
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Optimizing a "stop light" circuit to run on lower voltage

I am specifically talking about the circuit found here. I want to make this same circuit but make it run on much lower voltage, preferably a coin cell or two. Longevity is not important.
incomprehensibledisdain
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Single step debug and timer's counter value

I am debugging with cortex m7, i found that when I halt the CPU, the timer's counter value still upward increases. After reading it's reference maunal, I found a register that can stop timer's clock feed when the debugger halts the CPU. However,…
iouzzr
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Timer to provide a short pulse after a power-up delay

I've been searching for a long time for a timer circuit that activates a relay for a short time(less than 1 sec.) after a few seconds(5 to 10 sec) when the current is switched on. There are many circuits with a switch to activate the timer but for…
Marcel
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TS3005 Timer End of life...what should I do for an ultra low power astable?

I am working on a circuit with a Sharp Memory display that requires a VCOM 50% duty cycle square wave signal at a frequency of approx 1Hz. It was suggested to use a TS3005 (Datasheet)which looked perfect until I see that Silicon Labs has EOL (End of…
MarkW
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Jaycar short circuits Vol.1 bonus project 2: 3.5 minute timer

I have been trying to get this circuit working for sometime. Mechanically it works but when the potentiometer through which the capacitor charges is set to maximum the maximum timer period before the LED lights, or Buzzer goes off is roughly 12…
burton01
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Can there be a zero power timer?

Apologies before I dive into the question. This is the best title I could think of for a more complex question. Is it possible to have a timer circuit that consumes no power when quiescent? I mean that the circuit draws no power whatsoever, until…
Paul Uszak
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How are timers adjusted in a micro-controller?

In a 555 Timer the resistors and capacitors determine the frequency and the duration of the timer pulses. How is this actualized in case of a micro-controller timer?
user16307
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ON few hours OFF few hours timer circuit

I am very new at this, but I am looking for a simple circuit (no microcomputer please) that will turn ON an LED for 4-5 hours, then turn OFF for 20 - 19 hours. Then it will automatically repeat this loop for as long as there is power. This will be…
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Timers prescale and postscale

So i understand that a prescaler divides a clock, and PR2 is the period register which when the timer TMR2 reaches the value it increments from 0. Why is a post scaler needed to divide a non-clock signal. From the diagram it looks like the post…
Yogi Bear
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Help with 74HC393

I'm learning how to use ICs and am currently playing with a 74HC393. Since it contains 2 independent 4 bit binary counters I am trying to connect both sides of the chip to make them work together. Since this chip does not have a carry output I am…
Higgins
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CD4060 and 74HC4060

I am making a clock timer for an analog LED clock with ICs 4060 and 4027. The clock signal is going to drive some 4017s. Supply voltage would be from 5V to 9V. My online supplier site shows two 4060s- CD4060 and 74HC4060. Are they interchangeable?…
Vinodvnmy
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Simple coountdown timer IC that is independant of supply voltage

I'm designing a shutdown circuit that switches off a SMPS regulator after a 10 second time interval. This is a battery powered application and the battery voltage could be anywhere between 7-15V. I've looked at capacitor circuits and 555 timers and…
Jeremiah Rose
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