SN65LVDT101 3.3V PECL Termination

Kazuhiko Hirano

Genius 12583 points

Other Parts Discussed in Thread: SN65LVDT101

Hello,

Usually, PECL output termination is 50ohms to Vcc-2V.

However, looking at the figure38 on page 14 of SN65LVDT101 datasheet, it is 50ohms to GND, not 3.3-2.0V.

In this case, if Vcc=3.3V, Ioh/Iol can be calculated as around 45mA/32mA.

Can SN65LVDT101 really tolerate such high output current?

I think, in case of terminating to GND, usually 130-150ohms are used to avoid too much high output current, though.

Best regards,

K.Hirano

over 11 years ago

0 Michael Peffers over 11 years ago

TI__Mastermind 20820 points

Hi Kaz,

Figure 38 in the SN65LVDT101 data sheet is incorrect. The resistors would have to be of a larger value to prevent over driving the outputs or the termination scheme would have to change to the typical PECL termination that you pointed out.

Regards,

Mike

0 Kazuhiko Hirano over 11 years ago in reply to Michael Peffers

TI__Genius 12583 points

Hello Mike,

I see, thanks a lot!

Best regards,

K.Hirano

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SN65LVDT101 3.3V PECL Termination