> =

> sometimes you simply stare at the data sheet...thinking...hmmm...doenst m=
ake
> sense but it should.  So for example I was looking at the datasheet for t=
he
> ULN2803 located at =

> =

> http://www.st.com/stonline/books/pdf/docs/1536.pdf
> =

> >From what I gather, the different flavors are discussing the input contr=
ol
> voltage, not whats being switched?  Client is using the 2803A, being driv=
en
> from a PIC and is using it to switch 12V relays. Now they want to change =
to
> 24V relays...the part is rated on the transistors to 50V so shouldnt be a
> problem...right?  I just wanted to make sure I was reading the datasheet
> correctly, for those who have used this part in the past
> =


That's correct. The different flavors are designed for different kind of lo=
gic =

families (TTL, LSTTL, CMOS at various voltages and so on). The only thing t=
o =

look out for is that if the load current is increased so is the switch on =

voltage. Not much but if you are close to the limit it might be a problem. =
But, =

since you are switching to 24V relays instead of 12V the current should not=
 go =

up but down (with the same type of relay).

/Ruben
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D
Ruben J=F6nsson
AB Liros Electronic
Box 9124, 200 39 Malm=F6, Sweden
TEL INT +46 40142078
FAX INT +46 40947388
ruben@pp.sbbs.se
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D

-- =

http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist