Other Parts Discussed in Thread: SN65MLVD3, SN65LVDS180-Q1
To whom it may concern -
I need to set up an LVDS receiver for Failsafe State=LOW. I require a variant that
operates from -40°C to 125°C, such as e.g. the DS90LT012AQ-Q1.
In a related exchange it was commented that pulling down IN+ via 8k and pulling up IN- via 5k
results in -25mV across RT. According to threshold specifications of the DS90LT012AQ this will not result in Output=LOW:
VTH<=0V, typical value -30mV.
VTL>=-100mV, typical value -30mV.
Thus, a guaranteed Output=LOW requires a differential voltage of <-100mV across RT.
A bias current of about 1mA is required to achieve -100mV across RT. However app note
"AN-1194 Failsafe Biasing of LVDS Interfaces" recommends choosing a bias current at least one
order of magnitude smaller than the loop current (3mA).
Is there a way to set up the DS90LT012AQ-Q1 for Failsafe State=LOW? If not, is there any other LVDS
receiver for the operating range -40°C/125°C than can be?
Any feedback will be greatly appreciated, thank you in advance.
Best wishes, Rainer
