Will the analog out on a 6713 board source to a 75 ohm load?

[paul_r65]

Will the analog out on a 6713 board source to a 75 ohm load?  We have a 6713 board connected to a BNC-2110.  One analog out is connected to the input on a trigger circuit.  The analog out from the 6713/BNC-2110 is programmed to apply 5 volts.  The analog voltage has been measured at 5 volts, but when the trigger circuit is connected the voltage drops to 1.5 volts.

[Nathan_R]

Hi paul_r65,

The 6713 is not going to be able to provide 5 volts to a 75 ohm load. The analog outputs on the 6713 are rated to provide +/- 5 mA of current.  5 volts across 75 ohms will draw 66mA of current. The minimum load I would recommend using with a 5 volt output is 1k ohm.  This is because a 1k ohm load would draw 5mA. Any smaller load at 5 volts will draw more current than the 6713 can provide.

Can you increase the input impedance of your trigger circuit? If it has to stay at 75 ohm another option might be to control a relay with the 6713. The relay would switch on or off a higher current external voltage source that would power the trigger circuitry.

 The 6713 specifications can be found here. Please let me know if you have any questions.

Thanks,