NI 9401 TTL to non-TTL signal

[ibrahim42]

Hi Everybody,

I am using Labview FPGA modules. I want to trigger 5V relay.  I have got a NI-9401. This is 8 channel 5V TTL digital out module. But my relays isn't triggering with TTL signal.

Briefly, How Can I Use my TTL Signal to Generate a non-TTL Digital Signal?

Have a nice day!

[crossrulz]

What relay are you using.  Generally, relays need a good amount of current in order to switch.  DIO generally cannot source that much current (2mA for the 9401 from what I can gather from the datasheet).  So you may need to add a buffer circuit to get the current draw you need.

[ibrahim42]

Hi,

I am using relay in attachment. I think this problem is about inadequate current. You are right. Well, may I do buffer circuit with Labview? Or is the buffer circuit only hardware? Can you help me ?

[crossrulz]

That is quite a bit of coil current.  You may need a buffer chip and something like a Solid State Relay to control that relay properly.  Something like a SN74ACT245PWR  buffer chip with a DO061A SSR should do the job.

[ibrahim42]

Thank you for your advice