Other Parts Discussed in Thread: DS90UB635-Q1,
Tool/software:
We are still pursuing safety certification for a system using the DS90UB638-Q1 and a DS90UB635-Q1.
It would be very helpful to have additional information on the maximum possible output of the DS90UB638-Q1 RIN0+ pin.
The datasheet specifies a maximum output voltage of 260mV for a 50Ω terminated single ended system. This implies a max 5.2mA drive. This math also holds for the 100Ω differential termination @ 520mV.
We are not worried about 10mA or even 100mA out of this pin. We just need some verification that it can never exceed 500mA.
I know it sounds silly, but can you state that the DS90UB638-Q1 cannot drive >=100mA @ >=10Mhz at the supply voltage level regardless of internal or external termination?
Failure modes that might drive DC current are not an issue due to the external blocking capacitors. Our 1.8V supply rail is protected with Zeners and fuses to make sure it can't exceed 2.4V under any circumstances.
I am certain that the precision high frequency driver circuits in the 638 will fail well before they could switch 100mA, but it would be very helpful if you could support that assumption.
Thanks
