What is Timer: Definition and 126 Discussions

A timer is a specialized type of clock used for measuring specific time intervals.
Timers can be categorized into two main types.
A timer which counts upwards from zero for measuring elapsed time is often called a stopwatch, while a device which counts down from a specified time interval is more usually called a timer. A simple example of this type is an hourglass. Working method timers have two main groups: hardware and software timers.
Most timers give an indication that the time interval that had been set has expired.
Time switches, timing mechanisms which activate a switch, are sometimes also called "timers."

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  1. W

    Building a 1KHz Clock Signal Timer using a 555

    I need to build a timer(using a 555) with a frequency of about 1KHz and a duty cycle of about 25% to provide my clock signal. So the 555 is obliviously in astable mode. From my engineering data sheet: D=\frac{R_B}{R_A+2R_B} f=\frac{1.44}{\left(R_A+2R_B\right)C} where C is my capacitance value...
  2. J

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  3. J

    Creating a 556 Timer from Two 555s - Possible?

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  4. F

    Solving User Time Greater Than Real Time Problem

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  5. B

    Can the 555 timer be set to its maximum frequency of 500kHz?

    How would i do this?
  6. M

    Producing a Time Delay of 44 Seconds with a 555 Timer

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  7. D

    Triggering 555 Timer: How to Use PIC Microprocessor

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  8. N

    Solve 555 Timer Problem - Get 100kHz & 95% Duty Cycle

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  9. T

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  10. C

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  11. K

    Engineering Resistors in a 555 Timer Circuit

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  12. A

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  13. T

    Simple 555 timer circuit needed.

    Hi all, great forum here. Hope to learn a lot. I am looking for a sample LM555 circuit. In simple terms I am looking what I think to be a reverse of the monostable circuits I have seen. More or less I have a switch that needs to be held down for 1 sec before the circuit is active (pin 3...
  14. R

    Mk111 Variable interval timer

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  15. L

    What is the Relationship between Ticker-Tape Timer Tapes and Average Velocity?

    Homework Statement Refer to the uploaded file, Which of the following statements is/are correct? (1) The length of each tape represents the average velocity within the time interval. (2) The width of the tape represents the constant time interval. (3) Joining the centres of the tops of...
  16. N

    What am I doing wrong (555 timer as a one-shot)?

    What am I doing wrong (555 timer as a one-shot)?? I'm trying to use a 555 timer to produce a quick pulse whenever a switch is switched a certain way. I have it set up exactly as the data sheet describes (attached picture) and am using a 47 micro Farad Cap as C1 and a 1k ohm resistor. I have the...
  17. S

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  18. A

    Understanding Electric Motor Theory: A Guide for First Timers

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  19. R

    Using 555 Timer IC to Output 100 KHz Frequency

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  20. M

    How can I prevent my NE555 timer from being triggered upon power ON?

    Hi, My circuit is using NE555 timer to active a solenoid driver for some seconds. I have finally found out that any time we turn the power ON, the circuit is initially running. I have wondered that, when we turn the power ON, the power switch creates a signal as a voltage, so that can...
  21. M

    .Using a LM555 Timer to Power a 6V Solenoid

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  22. C

    Ticker Timer Experiment: Calculating Displacement, Velocity & Acceleration

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  23. Shahil

    Learn How to Program a 555 Timer for 4 Second Intervals | Tips and Tricks

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  24. U

    Morse Code IC Timer for Intercoms

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  25. N

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  26. X

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