current limited logic driver

Sebastian Ciesluk

Hi,

I am looking for logic driver 100k-50MHz, 3.3V with current limit at 20-40mA. Are you able to suggest anything from TI portfolio?

In other words it should have short circuit protection. The series output resistor is not an option as it drives lines with different impedances so 120 ohm (27mA) causes a lot of reflections. I have no influence on the line I am driving hence no chance for termination at the target.

If a device is not available are you aware of any app notes related to current limiting for logic drivers?

Could you please help with this.

Sebastian

over 15 years ago

0 Chris Cockrill over 15 years ago

TI__Mastermind 46480 points

We dont have any logic devices with short circuit protection. I think you could limit the output drive by a 10 ohm series resitor on the Vcc line. use something like the http://focus.ti.com/lit/ds/symlink/sn74lvc1g125.pdf

This is just a thought so I would advise testing it.

0 Sebastian Ciesluk over 15 years ago in reply to Chris Cockrill

Prodigy 20 points

Thanks Chris,

This is the solution I have planned if I can not find anything, I thought of being even more radical and creating separate current limited power supply for the driver .

The power supply will have 30 mA current limit. Do you recon the gate will work fine even during short with such a setup? I certainly will verify the circuit before production.

Thanks

Logic

Logic forum

current limited logic driver