the failsafe function of the LVDS transmitter

Status
Not open for further replies.
C

chang830

Full Member level 5
Joined
Feb 11, 2006
Messages
267
Helped
14
Reputation
28
Reaction score
3
Trophy points
1,298
Activity points
3,425
Hi,
For the LVDS transceivers, it is known that a failsafe functioon is needed for receivers because it is the small siganl detector. But I have some puzzles on the transmitters, why it also need the input failsafe protection part, considreing the TTL/CMOS input?

Thanks in advance
 

I also know a LVDS transmitter. But I didn't find the failsafe function.
Can you tell me what is failsafe function? Its purpose and how it is realized.

thanks!
 

It is doubt that the failsafe function is at the receiver
side.
 

hi, deal above all,
Pls. see the attached files. This is the datasheet of a quad LVDS transmitter from National Semiconductor. It ha the failsafe function at in floating inputs. I guess, when the input pin is in float status, it acts like as an antenna, it will trigger the LVDS transmitters to malfunction, just like LVDS receivers.

PLs. correct me if i am wrong.
 

Fail-Safe specification
In an LVDS interface, the fail-safe specification forces the receiver to provide logic-high level under certain input conditions. The receiver will output a logic high when one of the following conditions is true:
• The driver is disconnected from the receiver or powered off while the receiver is still powered on.
• The two lines of the differential pair become shorted.
• The inputs of the receiver are left open.
This fail-safe mode prevents the receiver from providing invalid data because of unexpected voltages on inputs.
 

so,, in the LVDS transmitter for which it has CMOS input from inside the chip,,is it required this failsafe or not????

thanks
 

Status
Not open for further replies.

Similar threads

Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…