A
ajcrm125
- Jan 1, 1970
- 0
Okay... I'm trying to create a circuit that interrputs a video signal
to a monitor. (Right now I'm using an old arcade monitor and arcade
game to test). The part I chose was the TI OPA3692 tripple video amp
with disable. Here's the datasheet:
http://focus.ti.com/general/docs/lit/getliterature.tsp?genericPartNumber=opa3692
Basically all I did was tie -Vs to GND, +Vs to +5V, attach the RGB
signals from the game to +IN A/B/C respectively, and the OUT A/B/C
signals to the monitor. I left the -INA/B/C signals floating so that
the amps would provide a +1 gain as specified in the datasheet. When
the disable pin is high (deasserted) the video looks normal, but when I
ground it the video dims but is still very noticeable. According to
the datasheet, disabling the amps puts them in a high-impeadance state.
I even threw some 100k pulldowns in the outputs to the monitor but no
difference. Is there something I'm missing here?
Input voltage levels off? Can't think of a reason why the disable
function would not work....
Thanks for any help guys.
-Adam Courchesne
to a monitor. (Right now I'm using an old arcade monitor and arcade
game to test). The part I chose was the TI OPA3692 tripple video amp
with disable. Here's the datasheet:
http://focus.ti.com/general/docs/lit/getliterature.tsp?genericPartNumber=opa3692
Basically all I did was tie -Vs to GND, +Vs to +5V, attach the RGB
signals from the game to +IN A/B/C respectively, and the OUT A/B/C
signals to the monitor. I left the -INA/B/C signals floating so that
the amps would provide a +1 gain as specified in the datasheet. When
the disable pin is high (deasserted) the video looks normal, but when I
ground it the video dims but is still very noticeable. According to
the datasheet, disabling the amps puts them in a high-impeadance state.
I even threw some 100k pulldowns in the outputs to the monitor but no
difference. Is there something I'm missing here?
Input voltage levels off? Can't think of a reason why the disable
function would not work....
Thanks for any help guys.
-Adam Courchesne