555 Timer? Input sawtooth 0-8 volts, Output adjustable pulse

[gmcjetpilot]

This is what I want to do:

Input: sawtooth from 0-8 volts with freq of 30 Hz to 60 Hz

Output: a pulse when input is at a user set voltage between 1-7 volts.
The pulse output is adjustable voltage (3-9v) and duration (5uS to 2mS)

I'm flexible, it is not super critical. I just need a stable trigger even if it has some delay.

If some one can draw out a circuit I would appreciate it.
The 555 timer seems to be the way to go?

Thanks

 

[IanP]

Re: 555 Timer? Input sawtooth 0-8 volts, Output adjustable p

555 is not that flexible, it has “fixed” thresholds and the output pulse is more the less the same as the supply voltage ..
However, you can do almost all what you’ve described with PICAXE-08 ..
Have a look at the attached picture .. it’s self-explanatory ..
P1 can be programmed to “read” the amplitude of the incoming signal, whereas P2 can be programmed to control the width of the output pulse ..
If you vary [V+], that’s the voltage that supplies the output driver, you can vary the “height” of the output pulse ..

Rgds,
IanP

 

[gmcjetpilot]

Re: 555 Timer? Input sawtooth 0-8 volts, Output adjustable p

555 is not that flexible, it has “fixed” thresholds and the output pulse is more the less the same as the supply voltage ..
However, you can do almost all what you’ve described with PICAXE-08 ..
Have a look at the attached picture .. it’s self-explanatory ..
P1 can be programmed to “read” the amplitude of the incoming signal, whereas P2 can be programmed to control the width of the output pulse ..
If you vary [V+], that’s the voltage that supplies the output driver, you can vary the “height” of the output pulse .. Rgds,
IanP

Hey I was not familiar with the PICAXE-08.... I guess it is a micro controller. Very Cool.... I looked into it a little and it would be fun to learn. Thanks

 

[E-design]

Re: 555 Timer? Input sawtooth 0-8 volts, Output adjustable p

One way doing it with common parts will use a window comparator (2), 2 gates, D type FF and some R&C's

MCU is the more elegant solution