555 EFI

[thergen at svn.net]

On Sat, 16 Jan 1999, Clarence L.Snyder wrote:

> thergen at svn.net wrote:
> > 
> > Picture an op-amp with the non-iverting input connected to pin 6 and the
> > inverting input connected to pin 5.  Pin 5 is also connected to a resistor
> > divider network that pulls it to 2/3 Vcc.  There is probably a symbolic
> > view on one of the semiconductor manufacturers sites.  I'm looking at the
> > cover of two different books that show this configuration.
> > 
> > The 2/3 reference point can be yanked around to where you want by using
> > pin 5.  It can also affect the 1/3 reference for pin 2.
> > 
> 
> So this pin 5 could be labelled "offset?" In other words, it changes the
> voltage that 2/3 of must be reached to trigger? Or put another way, does
> it change the reference voltage of the comparator?
> > >
> 
Yes, pin 5 can change the reference voltage of the comparator and could be
labelled an "offset".  Pin 5 is tied directly to the reference voltage of
the comparator (for pin 6) in the symbolic picture I have of a 555.

Tom