LMX2594: RF output termination (LVDS)

Gajendiran A

Part Number: LMX2594

I am connecting the LMX2594 RF output to the fanout buffer. The frequency we are working on is between 150MHz - 200MHz.

The fanout buffer input signal type is LVDS, and the LVDS termination has to be differential AC Coupled input termination as below.

Fanout buffer differential (HCSL, LVPECL, Low-Power LVPECL, LVDS, CML) AC Coupled input termination:

LMX2594 RF Output:

Please suggest, What is the value of R1 and R2 for LVDS and LVPECL signals?

Thank you!!

over 2 years ago

0 Noel Fung over 2 years ago

TI__Guru** 107110 points

Hi there,

What is the input voltage specification of your LVDS receiver?

0 Gajendiran A over 2 years ago in reply to Noel Fung

Prodigy 225 points

Hi Noel,

The Vdd voltage is 3.3V

Regards,

Gajendiran A

0 Evan Su over 2 years ago in reply to Gajendiran A

TI__Mastermind 18705 points

Hi Gajendiran,

Thanks for the information, Noel is currently out of the office but a team member will assist you soon.

Best,

Evan Su

0 Ajeet Pal over 2 years ago in reply to Evan Su

TI__Genius 12560 points

Hi Gajendiran,

LMX2594 has ~8/10dBm single ended output with 50 ohm load (with OUTx_PWR = 50) at these frequencies. Using the lower OUTx_PWR setting, RFout power further reduced around 0dBm single ended, which can be acceptable for LVDS buffer with the maximum differential input swing 2.2V.

Thanks!

Regards,
Ajeet Pal

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LMX2594: RF output termination (LVDS)