Electronic & Computer: timer

Showing posts with label timer. Show all posts

Wednesday, April 14, 2010

Timer circuit

This is timer circuit, , which compose the circuit controls, delay the work.
When expire warn or use control other get. The majority is will the circuit is simple,
then build not difficult. For example NE555 integrated circuit leads come to are usable,
The circuit delays with the transistor and other again many the circuit.

555 Asymmetric Timer
A simple astable timer made with the 555, the mark (on) and space (off)
values may be set independently. The timing chain consists of resistors Ra, ...

555 Timer 5 to 30 Minute
However you must use the CMOS type 555 timer designated the 7555,
a normal 555 timer will not work here due to the resistor values. ...

Timer Plus Relay by IC 555
Timer Plus Relay by IC 555. ... Use IC 555 Timer (HOT IC) and Relay 6V ,
Volt supply 9V. R1 and C1 control timer relay 11 S. Trigger circuit pin 2 to switch ...

Voltage Controlled Switch using 555 Timer
IC 555 Circuit, Voltage Controlled Switch using 555 Timer. ... In this circuit the 555 timer
is used in a novel way, as a voltage controlled switch. ...

Car Burglar Alarm timer delay using NE556
12 Jan 2009 ... Car Burglar Alarm timer alarm system circuit , model to economize.
This circuit convenients for to set up in an automobile. usually switch ...

One - Shot Timer by IC 555
This is digital circuit, It is One - Shot Timer make by IC 555. Power supply 5-15V, Output pin 3,
Input pin 2 Trigger input. One - Shot Timer by IC 555.

Astable Timer with PIC 12F629 - 12F675
5 Jun 2009 ... This software functions as a long period astable mutivibrator.
The mark and space period can be set from 1 second up to a maximum 65535 ...

PIC16F628 Digital Clock Timer
1 Feb 2008 ... This clock timer uses a PIC16F628 microcontroller to display 3 and 1/2 digit
time and control an external load. It can be programmed to time ...

Basic Timer By IC Quad Timer LM558
23 Jul 2007 ... Basic Timer By IC Quad Timer 558 Today I begs for to advise
the circuit timer the foundation. By use the integrated circuit number LM558 (IC ...

RS - Flip-Flop Made With A LM556 Timer
5 Sep 2009 ... The circuit on this page is for a hybrid - SET / RESET type of
logic Flip-Flop that is constructed from an LM556 - Dual Timer integrated ...

Power Saver & Timer Kit
12 Sep 2009 ... This little timer kit can be easily added to any existing project
to allow for automatic shutoff. Tons of applications; heating, cooling, ...

D - Flip-Flop Made With A LM556 Timer
23 Aug 2009 ... This circuit is a hybrid - D type Flip-Flop that is constructed from an LM556 -
Dual Timer integrated circuit. The circuit is essentially a ...

One-Shot By IC Quad Timer 558
23 Jul 2007 ... One-Shot By IC Quad Timer LM558 When mention the circuit One Shot friends
at take an interest digital side may know good that how much is it ...

ZN1034E Timer
This entry was posted on Sunday, May 20th, 2007 at 3:23 pm and is filed under Audio - Alarm,
Circuit, Timer. You can follow any responses to this entry ...

Relay Timer switch By IC 555 and 741
29 Aug 2007 ... In Fig.1 see a 100 second delayed turn ON relay RL1 switch, if plug power +12V
in circuit. In Fig.2 see a two range 6-60 second and 1-10 ...

Basic 555 Timer Oscillator
26 Apr 2008 ... The circuit on the left shows the standard astable oscillator circuit for
the NE555N IC. This si the basic circuit that is shown in most ...

555 timer as a switch-mode power supply
27 Dec 2007 ... Most switch-mode power supplies rely on a PWM (pulse-width-modulated)
output that is controlled via voltage feedback. A 555-timer IC can ...

Basic Timer Control with NE555
13 Aug 2008 ... As friends many take an interest the circuit about IC 555 which
be integrated highly popular that circuit. I then lead the circuit sets the ...

Circuit Egg Timer By LM555
22 May 2007 ... Click to View Circuit Egg Timer By 555 This is Easy and Mini Timer Circuit
( Egg Timer) by IC 555. Alarm by Buzzer. This be mini timer ...

simple timer with IC 4093 + 7808
31 Aug 2007 ... The on time of the timer is set by the one shot built with R2/R3 C3 and IC2A:
after pressing pushbutton S1 C3 will be charged slowly through ...

Circuit Egg Timer By 555
IC 555 Circuit, Circuit Egg Timer By 555. ... This is Easy and Mini Timer Circuit
( Egg Timer) by IC 555. Alarm by Buzzer. Circuit Egg Timer by LM555 ...

LM555 Timer Used As A Voltage Comparator Or Schmitt Trigger
22 Oct 2009 ... The next section shows how the LM555 timer could be used as
a voltage comparator or a wide offset Scmitt Trigger. Applications for which it ...

555 timer pulse generator
31 Jan 2008 ... To drive ignition coils is to use a 555 timer pulse generator.
A 555 generates a square wave output that triggers the 2N3055.

Basic Timer using FET 2N3819
8 Sep 2008 ... This circuit be Basic Timer Circuit by use important equipment is FET 2N3819.
By this circuit can can delay long ago arrive at 1.5 minute.

Timer Circuit by FET + Transister
20 May 2007 ... Circuit Timer Circuit by FET + Transister. ... ZN1034E Timer
LED Chaser by IC 4017 + IC 555 ». Timer Circuit by FET + Transister ...

Tan Timer by IC 4060 and IC 4017
26 Oct 2008 ... Six timing positions suited to different skin types Timing affected
by sunlight intensity Six timing positions suited to different skin ...

Touch Switch low cost by Timer IC 555
15 Oct 2008 ... This Touch Switch circuit use a part compares with voltage 2 group,
within the integrated circuit timer LM555 or NE555.

Timer Plus Relay by IC 555
29 Jun 2007 ... This be Timer Plus Relay Circuit by IC 555. When see the circuit also
a little equipment. By the value R1 and C1 perform set the time give ...

Fully Adjustable Pulse Generator By IC Quad Timer 558
29 Jul 2007 ... Fully Adjustable Pulse Generator By IC Quad Timer LM558 Be the circuit
that is valuable very , because frequency pulse fine get freely do ...

Sunday, January 6, 2008

Time Delay Relay II by IC 4011

When activated by pressing a button, this time delay relay will activate a load after a specified amount of time. This time is adjustable to whatever you want simply by changing the value of a resistor and/or capacitor. ...

Link Time Delay Relay II by IC 4011

Time Delay Relay by 555

A time delay relay is a relay that stays on for a certain amount of time once activated. This time delay relay is made up of a simple adjustable timer circuit which controls the actual relay. ...

Read more and View Circuit

Wednesday, May 30, 2007

24 Hour Timer by IC 4060

Source :: http://www.zen22142.zen.co.uk/Circuits/Timing/24hour.htm

Circuit : Ron J
Email Ron

Description:
These two circuits are multi-range timers offering periods of up to 24 hours and beyond. Both are essentially the same. The main difference is that when the time runs out, Version 1 energizes the relay and Version 2 de-energizes it. The first uses less power while the timer is running; and the second uses less power after the timer stops. Pick the one that best suits your application.

Notes:
The Cmos 4060 is a 14 bit binary counter with a built in oscillator. The oscillator consists of the two inverters connected to Pins 9, 10 & 11; and its frequency is set by R3, R4 & C3.The green Led flashes while the oscillator is running: and the IC counts the number of oscillations. Although it's a 14 bit counter, not all of the bits are accessible. Those that can be reached are shown on the drawing.

By adjusting the frequency of the oscillator you can set the length of time it takes for any given output to go high. This output then switches the transistor; which in turn operates the relay. At the same time, D1 stops the count by disabling the oscillator. Ideally C3 should be non-polarized; but a regular electrolytic will work, provided it doesn't leak too badly in the reverse direction. Alternatively, you can simulate a non-polarized 10uF capacitor by connecting two 22uF capacitors back to back (as shown).

Using "Trial and Error" to set a long time period would be very tedious. A better solution is to use the Setup tables provided; and calculate the time required for Pin 7 to go high. The Setup tables on both schematics are interchangeable. They're just two different ways of expressing the same equation.

For example, if you want a period of 9 Hours, the Range table shows that you can use the output at Pin 2. You need Pin 2 to go high after 9 x 60 x 60 = 32 400 seconds. The Setup table tells you to divide this by 512; giving about 63 seconds. Adjust R4 so that the Yellow LED lights 63 seconds after power is applied. This will give an output at Pin 2 after about 9 Hours.

The Support Material for the timers includes a detailed circuit description - parts lists - a step-by-step guide to construction - and more. A suitable Veroboard layout for each version is shown below:

The timer was designed for a 12-volt supply. However, provided a suitable relay is used, the circuit will work at anything from 5 to 15-volts. Applying power starts the timer. It can be reset at any time by a brief interruption of the power supply. The reset button is optional; but it should NOT be used during setup. The time it takes for the Yellow LED to light MUST be measured from the moment power is applied. Although R1, R2 and the two LEDs help with the setup, they are not necessary to the operation of the timer. If you want to reduce the power consumption, disconnect them once you've completed the setup. If you need a longer period than 24-hours, increase the value of C3.

555 Asymmetric Timer

Source :: http://www.zen22142.zen.co.uk/Circuits/Timing/asym.htm

Circuit : Andy Collinson
Email: anc@mitedu.freeserve.co.uk

Description:
A timer circuit with independent mark and space periods.

Notes:
A simple astable timer made with the 555, the mark (on) and space (off) values may be set independently. The timing chain consists of resistors Ra, Rb and capacitor Ct. The capacitor, Ct charges via Ra which is in series with the 1N4148 diode. The discharge path is via Rb into into pin 7 of the IC. Both halves of the timing period can now be set independently.

The charge time (output high) is calculated by:

T(on) = 0.7 Ra Ct

The discharge time (output low) is calculated by:

T(off) = 0.7 Rb Ct

Please note that the formula for T(on) ignores the series resistance and forward voltage of the 1N4148 and is therefore approximate, but T(off) is not affected by D1 and is therefore precise.