10 Minute timer circuit.
Description.
When ever you need to get an alarm or intimation after ten minutes ,the circuit shown below can be used.The circuit is nothing but a monostable multivibrator based on IC NE 555.When ever you press the reset push button the green LED D1 glows after 10 minutes.
Circuit diagram with Parts list.
Notes.
- Assemble the circuit on a good quality PCB or common board.
- The time duration can be set by varying the POT R5.
- The switch S1 can be a push button switch.
- The IC1 must be mounted on an IC base.
Can the D1 LED be replaced with a buzzer?
Siri Johnsen
Can the D1 LED be replaced with a buzzer?
Yes it can provided you have used a NE555 chip. If you haven’t used a NE555 then if it doesn’t work its most likely the 555 can’t handle the current.A transistor would then be required as well.
Most buzzers come with a rated voltage and current. The voltage isn’t too serious as most buzzers will operate from 1.5V – 20V even if it says 5V(depending on manufacturer). If it’s a 5V buzzer it should work just as well off of 9V as off 5V.
The chances are good that it would draw about 10-15mA when fully switched on.
For convenience sake I would leave R2 at 330 ohm’s but 500ohms would be closer to the mark.
can i use a IC LM 555 in this diagram showed?
or can i use any IC LM in the other diagram?
thank you!!!!!!
you can use LM555 instead of NE555.
LM555 is a direct replacement for NE555 and SE555 timers.
Just have a look at the datasheets of these ICs.You will understand it.
can you give me a layout sample of this diagram??
Can the resistor R5 be adjust to varies the timer duration?
yes R5 can be adjusted to vary the time duration
Dear Johnson you can replace the LED with an electronic music generators (similar to car reverse horn). It is a two lead device with built in ceramic sounder and the required electronics to produce beeps or continuous tone etc. this device can operate from 3 to 15 volt with the out put sound level varying. Delete R3. Wishing you Happy construction and enjoyment.
that timer is very good. i use it as washing machine timer. thank you!
Dear Johnson,
I got a small problem in form of a circuit that can control
a relay by a signal (12V)so it can be adjusted just like your circuit.
What i need is a circuit so i can adjust relay on time
around 1 – 20 min for example after been triggered.
If you could help me i would be very greatful
Best Regards
Kjell.
dear people
guys i would like to change it for 5hrs timer and trigger device with alarm. what i would change?
for watchdog purposes.
Dear Harley The maximum capacitance you can use is 470uF and resistance 2.2M. with the internal leakage of 470uF, 2.2M may not be in a position to charge the capacitor at all. hence 1M and 330uF are the practically the highest values you can use. The delay cannot be greater than 10 to 15 mts. even an hr delay is not possible.
you may use this as a low frequency astable and use mutistage deviders to achieve the required time delay.
can we use 7 segment display by using 555IC for 10 minute timer or do we need any other IC ? please suggest?