flasher - Electronic Circuits Projects Diagrams Free

Silverker · 6th May 2006, 02:19 AM

Does any1 know where I could find a schematic for a timmer circuit that will allow a "flash**flash**flash**steady on" pattern for a 12 volt system?

Russlk · 6th May 2006, 04:32 AM

Here is a circuit. It will flash the load 3 times then stay on until the power is removed. You can calculate the R and C values from the 555 data sheet. Use a MOSFET rated for the current of the load. If the load is inductive, use a snubber diode. filter the 12 volts if this is an automotive application. Oops, Should have made the 555 timer duty cycle closer to 50 %! See the 555 data sheet.

hotwaterwizard · 6th May 2006, 06:54 AM

How many Amps load?

Silverker · 7th May 2006, 03:23 PM

it's a 5W/12V lamp. Correct in the assumption about automotive. Where I live "legally" you are suppose to flash your brake light on a motorcycle before you actually stop. I want to do it automatic. any other thought or help on this project would be appreciated because I only have a little of the basics down good.

Russlk · 7th May 2006, 08:08 PM

Now that I know more about the application, I have updated the schematic:

Silverker · 8th May 2006, 02:19 AM

what is the delay on the flashing? Do you know a good place to find the parts (when I looked on radioshack.com it didn't find the fqp3n80 and cd40175b) or are there other part numbers for them? Also, do I need to connect all the grounds and that be my output to the light? I'm not sure where wire 11 actually connects to. Are all the logic gates the same part number ( I noticed that 2 of them had 3 connections and the other 2 had 4). Does the VDD connect to pin 16 on the flip flop? Where is pin 8? The 1st symbol that you used I'm not familiar with is it a coil? Thank you for being patient with a newbie and helping me with this.

Cool_buddy_57 · 8th May 2006, 08:29 AM

PLz used a monostable Multivibrator it is a easy flasher Circuit

Russlk · 8th May 2006, 02:32 PM

The flash rate is one second (3 flashes in 3 seconds). You can make it faster by making the 470K resistors smaller. Order parts from Mouser (www.mouser.com); I put Mouser part numbers on the schematic. Mouser does not have a minimum order. Radio Shack does not carry useful parts anymore! Yes, the grounds are common, and it occurred to me that the tail light is grounded to the frame, so it would be dificult to operate in my original design, so I have modified the schematic again. Pin 11 is not used, leave it open. Yes, VDD is +12 volts on pin 16 and ground is connected to pin 8. It is common practice to leave the power pins off the symbol, because you can find them on the data sheet. Data sheets are available at Mouser.com. Yes, the curly symbol is a coil.

Silverker · 8th May 2006, 04:34 PM

would it still work if increasing the 470K resistors larger to make it a slower rate?

**Nigel Goodwin** · 8th May 2006, 04:36 PM

Quote:

Originally Posted by Silverker

would it still work if increasing the 470K resistors larger to make it a slower rate?

Yes, it's just a standard 555 oscillator.

Silverker · 8th May 2006, 05:02 PM

there is nothing "standard" in my life

Silverker · 8th May 2006, 06:24 PM

When I looked up the capacitor labeled 647-UPW1H0MDD it wasn't found. What's the voltage on that one?

**Nigel Goodwin** · 8th May 2006, 10:14 PM

Quote:

Originally Posted by Silverker

When I looked up the capacitor labeled 647-UPW1H0MDD it wasn't found. What's the voltage on that one?

I'll give you a clue! - the power supply is only 12V, so as long as it's more than that it will be fine. However, a 1uF is likely to be either 63V or 100V, and still be small.

Russlk · 8th May 2006, 10:50 PM

It is hard to tell the difference between "o" and zero, so that is probably why it was not found. And, I don't know which it is.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

6th May 2006, 02:19 AM	#1
Silverker	flasher Does any1 know where I could find a schematic for a timmer circuit that will allow a "flashflashflash**steady on" pattern for a 12 volt system?

6th May 2006, 04:32 AM	#2
Russlk	Here is a circuit. It will flash the load 3 times then stay on until the power is removed. You can calculate the R and C values from the 555 data sheet. Use a MOSFET rated for the current of the load. If the load is inductive, use a snubber diode. filter the 12 volts if this is an automotive application. Oops, Should have made the 555 timer duty cycle closer to 50 %! See the 555 data sheet. Attached Thumbnails __________________ see my website: www.geocities.com/russlk Last edited by Russlk; 6th May 2006 at 12:44 PM. Reason: Error in schematic

6th May 2006, 06:54 AM	#3
hotwaterwizard	How many Amps load? Attached Thumbnails __________________ John DeRosa (Hotwaterwizard) hotwaterwizard@aol.com

7th May 2006, 03:23 PM	#4
Silverker	it's a 5W/12V lamp. Correct in the assumption about automotive. Where I live "legally" you are suppose to flash your brake light on a motorcycle before you actually stop. I want to do it automatic. any other thought or help on this project would be appreciated because I only have a little of the basics down good.

7th May 2006, 08:08 PM	#5
Russlk	Now that I know more about the application, I have updated the schematic: Attached Thumbnails __________________ see my website: www.geocities.com/russlk

8th May 2006, 02:19 AM	#6
Silverker	what is the delay on the flashing? Do you know a good place to find the parts (when I looked on radioshack.com it didn't find the fqp3n80 and cd40175b) or are there other part numbers for them? Also, do I need to connect all the grounds and that be my output to the light? I'm not sure where wire 11 actually connects to. Are all the logic gates the same part number ( I noticed that 2 of them had 3 connections and the other 2 had 4). Does the VDD connect to pin 16 on the flip flop? Where is pin 8? The 1st symbol that you used I'm not familiar with is it a coil? Thank you for being patient with a newbie and helping me with this. Last edited by Silverker; 8th May 2006 at 03:47 AM.

8th May 2006, 08:29 AM	#7
Cool_buddy_57	PLz used a monostable Multivibrator it is a easy flasher Circuit

8th May 2006, 02:32 PM	#8
Russlk	The flash rate is one second (3 flashes in 3 seconds). You can make it faster by making the 470K resistors smaller. Order parts from Mouser (www.mouser.com); I put Mouser part numbers on the schematic. Mouser does not have a minimum order. Radio Shack does not carry useful parts anymore! Yes, the grounds are common, and it occurred to me that the tail light is grounded to the frame, so it would be dificult to operate in my original design, so I have modified the schematic again. Pin 11 is not used, leave it open. Yes, VDD is +12 volts on pin 16 and ground is connected to pin 8. It is common practice to leave the power pins off the symbol, because you can find them on the data sheet. Data sheets are available at Mouser.com. Yes, the curly symbol is a coil. Attached Thumbnails __________________ see my website: www.geocities.com/russlk

8th May 2006, 04:34 PM	#9
Silverker	would it still work if increasing the 470K resistors larger to make it a slower rate?

8th May 2006, 05:02 PM	#11
Silverker	there is nothing "standard" in my life

8th May 2006, 06:24 PM	#12
Silverker	When I looked up the capacitor labeled 647-UPW1H0MDD it wasn't found. What's the voltage on that one?

8th May 2006, 10:50 PM	#14
Russlk	It is hard to tell the difference between "o" and zero, so that is probably why it was not found. And, I don't know which it is. __________________ see my website: www.geocities.com/russlk