voltage to Freq converter

[BrownOut]

Hi, you have some problems with your connections. I will write more when I get back to town ( on the road right now )

 

[snooze]

looking forward to your reply..

 

[BrownOut]

V- for the5V connected to Rpu, and v- for the 0-10V source should be connected to the "common" point. You have them connected to -15V.

 

[snooze]

Thanks. i sorted out the circuit connection

Now the output Fout at pin 7 is inverted.

i connected a pull-up resister to 5V as indicated in circuit. anybody can help?

picture in next post?

 

[snooze]

**broken link removed**

 

[BrownOut]

Why don't you tell us what those traces are? We can't read your mind.

If the top trace is fout, then it should be inverted. That's what the output transistor does.

 

[snooze]

Fout should be this waveform. the Vint waveform pass thru the one shot circuitry.


but my circuit Fout produced this waveform. it seems like a inverted.

 

[BrownOut]

Look at the timing relationship between your waveform and the published one. They are the same. What exactly do you think is wrong? What value resistor did you use for the pullup? Your output should be a square wave, so I'm thinking your pullup is too low.

 

[snooze]

Why don't you tell us what those traces are? We can't read your mind.

If the top trace is fout, then it should be inverted. That's what the output transistor does.

so output waveform inverted is correct? the duty cycle of my Fout is opposite of the published schematics.

i am using 4.7KOhms as pull-up resistor for 5V.

 

[BrownOut]

Ok you're right, it is inverted ( I'm cross-eyed this morning ) And it's distorted. The good news is you're much closer than you were before. Check your pullup resistor with an ohmmeter, make sure it's connected to positive voltage, that you don't have the pullup voltage reversed, disconnect anything else from the output. At this point, it's a matter of carefully checking your connections.

 

[snooze]

ok. will check thoroughly. Tks