regarding opto isolators

Hi all,

I was studying some board schematics. In this there are some clocks coming from external world . Before these clocks are connected to the FPGA pins they pass through an opto isolator.Could any body help me out why the opto isolators are really required .

rgds, prav

Reply to
prav
Loading thread data ...

They usually required when the signal source has the different ground potencial than FPGA has. Often it occurs when the signal source is far from FPGA and the signal and ground wires make a pair to prevent noise errors. In the medical installation it is the usual practice because of voltage shield of patients.

But the opto isolator usually does not support the high clokck frequency.

A.Ser.

Reply to
Vladislav Vasilenko

Hi Vladislav,

As u told that optoisolator dosen't support high clock frequency . Are there any other alternatives to replace a opto isolator so that i can work at higher frequency.

rgds, prav

Reply to
prav

Phototransistors are slower than photodiodes, and LEDs are slower than laser diodes, though maybe fast enough. You might try a separate laser diode photodiode pair.

-- glen

Reply to
glen herrmannsfeldt

IsoLoop has isolators that run up to 35 Mbps.

formatting link

Reply to
Eric Smith

formatting link

optical isolation for data rates 100M

antti

formatting link

Reply to
Antti Lukats

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.