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Output a +5V TTL on a PFI term. to a 50Ohm load (M-serie or S-serie)

Hi,

I can export AnalogComparisonEvent to any terminal like PFI0. This signal is supposed to be a TTL with max = +5V.

But it seems the impedance of the PFI is not 50Ohm, because when I look the signal on a scope (terminated 50Ohm), the maximum is at only 2.4V.

Can I change this impedance ? How can I manage otherwise to get a +5V TTL on a (50 Ohm load) out of my card ?

 

Config. : a PCIe 6259 (M-serie) or a PCI 6110 (S-serie), with BNC-2110 or BNC2120.

 

Thanks !

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external hardware buffer/driver , powered by the provided 5V

Greetings from Germany
Henrik

LV since v3.1

“ground” is a convenient fantasy

'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'


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Thanks. So no other option than to use an additional external device that will amplify then signal, that's it ?

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If you use more that one PFI and parallel them ... but I don't recommend that.

read the spec, all expected behaviour..   If you increase the load impedance you get closer to to 5V.  50Ohm is no typical TTL input 😉

What is the problem? 2.5V is fine to trigger something 😄

Greetings from Germany
Henrik

LV since v3.1

“ground” is a convenient fantasy

'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'


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