Try this:

   PIC Output pin
         |
   +-----+------+
   }            |
   |            |
   |           ---
   |           ---    .1 to 2.2 uFd - value depends on drive pulse
   |            |                     rate, use smaller value with
   |            |                     higher rates	
   |            |         
   \            \ 
   / 1K         /
   \            \      10-100 Ohms - may not even be needed.
   /            /                     Limits peak current
   \            \                     from output pin.
   |            |
   |            |
   |     /------+
   |  | /       | //
   |  |/       ---  
   +--|   LED  / \     
      |\|      ---  
      | \       |      
 2N3904  |      |   
         |      |
        ---    ---
        ///    ///

The LED will appear to be on solid when the pulse rate is more 
than 30 per second.



On Wed, 14 Jan 1998 09:16:58 +0200, you wrote:

->Trying to run a PIC 16F84 with 2V i came to tihnk if there is any
->possibilities to make a LED to run with only one NiCd that has the
output
->valtage of about 1.2 V. Led needs about 1.6 V.
->The system should not have any fancy IC's and it should fit in the
size of
->half of an AAA-cell.
->
->Virtual beer for the best idea !
->
->--------------------------------------------------------------------------
->PTM, pasi.mustalahti@utu.fi, ptmusta@utu.fi,
http://www.utu.fi/~ptmusta
->Lab.ins. (mikrotuki) ATK-keskus/Mat.Luon.Tdk
OH1HEK
->Lab.engineer (PC support) Computer Center
OI7234
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