Can I use the output of the PC-TIO card to drive 5V into a 50 ohm load?

[rfrechen]

I am using the output of the PC-TIO as a trigger for a 20-year old YAG laser. The trigger requirement calls for a TTL-compatible signal that will give a 5V pulse into 50 ohm. The PC-TIO output only gives about 350 mV when measured on a scope set to 50 ohm input impedance. Attempts to "condition" the signal externally have failed. Any ideas?

[RobertoBozzolo]

Your device can output a maximum current of 10 mA. A 50 ohm load on a 5 V supply will drain 100 mA from the device, that is your card will fail in drive the unit connected, with the risk of damaging the card itself.

In this case you can use PC-tio to drive a traditional relay, a SSR or a transistor connected to an external 5 V supply capable of the required current for the device to drive. We usually use ULN2003 for this purpose: it's a 7-output high current driver.

In case of a traditional relay, since there can be a delay between card output and contact switch (up to tenths of msecs depending on the type of relay) you should consider it in your program if time consideration are relevant to you.

Roberto