1. Jan 29, 2009 #1

   simo

   

   Can you tell me what is wrong with my timer. I want it to make a relay open and shut periodically. For some reason it's not working.

    

   Attached Files:

   • 

     555 timer.doc

     File size:

     41.5 KB

     Views:

     91

   simo, Jan 29, 2009
2. 
   Phys.org - latest science and technology news stories on Phys.org

   • • Engineers devise two-way radio on a single chip
   • • Researchers to develop new math theory for improvement of imaging technology
   • • New technology platform propels the use of 'organs-on-chips'
3. Jan 29, 2009 #2

   berkeman

   

   Staff: Mentor

   You show your output directly shorted to ground. Is that correct, or a typo?

    

   berkeman, Jan 29, 2009
4. Jan 29, 2009 #3

   simo

   

   Nope, that's how I made it.
   
   If I disconnect the output/diode junction from ground, would it sink the current?

    

   simo, Jan 29, 2009
5. Jan 29, 2009 #4

   dlgoff

   

   Science Advisor

   Gold Member

   If you do the calculation from the numbers you give, the sink current would be about 11ma, so the 555 should be able to sink that.

    

   dlgoff, Jan 29, 2009

• Log in with Facebook
• Log in with Twitter

Your name or email address:

Do you already have an account?

• No, create an account now.
• Yes, my password is:
• Forgot your password?

Stay logged in