switch on 2.1v and 2.5v

[Nick]

I am trying to make a switch on 2.1 volts and anther switch to turn on at 2.5 volts without using the PIC. The wire will have between 2v and 4v and I would like the switch to supply +5v for true and 0v for false. Does anyone have any pointers?


analog line
(2v-4v)________________---Switch----(+5v or 0v)

Nick

[Charlie U]

I am not certain what you are trying to do, but it sounds like you could use an analog switch such as a TI CD74HC4066. Take a look at this link and see if it is what you are looking for.

http://focus.ti.com/docs/prod/folders/print/cd74hc4066.html

Or are you trying to create 0 and 5V from the analog line? In that case, you could use a comparator such as an LM393. Look at the data sheet and some of the app notes. You may want to add a bit of hysterisis to give some noise rejection.

http://www.national.com/pf/LM/LM393.html

[Neutone]