Connections of devices with differential inputs/outputs

[amko]

Hello

I have SERDES device from TI (TLK2501) which I want to connect to
optical transciver from Intel (TXN31111). SERDES generates differential
output preemphasis 1680 mVpp (min)... 2520mVpp (max) and deemphasis
1520mVpp to 2280mVpp (max). Input Leves in SERDSE are 400mVpp (min)..
(not given in datasheet max).
Optical transciver has CML logic levels waht means CML input is 400mVpp
(min) to 2000mVpp. CML output levels are 500mVpp (min) ..1200mVpp(max).
Optical transciver has internal AC Coupling.
So I am interesting how I can connect these two devices or in other
words how should look adaption circuit (level converter).

Thank you for Your answers,

Regards,
Amir

 

[Rene Tschaggelar]

Hello

I have SERDES device from TI (TLK2501) which I want to connect to
optical transciver from Intel (TXN31111). SERDES generates differential
output preemphasis 1680 mVpp (min)... 2520mVpp (max) and deemphasis
1520mVpp to 2280mVpp (max). Input Leves in SERDSE are 400mVpp (min)..
(not given in datasheet max).
Optical transciver has CML logic levels waht means CML input is 400mVpp
(min) to 2000mVpp. CML output levels are 500mVpp (min) ..1200mVpp(max).
Optical transciver has internal AC Coupling.
So I am interesting how I can connect these two devices or in other
words how should look adaption circuit (level converter).

Thank you for Your answers,

When the output voltage is bigger than the allowable input,
a resistor divider can be used. Build a divider that
has the mean DC of the line as base. Or perhaps a
three resistor divider, with the outer connects as inpit
the inner connects as output. Since you're
counting picoseconds, the resistorvalues should be
sufficiently low.

Rene