TFP410: What is the clock of the differential signal outputs?

Matthew Chen

Part Number: TFP410

Hi team,

1. The input signal customer used is 148.5MHz and configured TFP410 according the datasheet. There is no signal captured by using 500Mhz and 1Ghz bandwidth oscilloscope. Customer wants to know the clock of the differential signal outputs to classify if they use the wrong measure method. Do you have any comment on that?

If the reason is not the oscilloscope, the problem comes from the wrong configuration of the registers.

2. For the CTL_1_MODE register, when power up the chip, what should be written to TDIS and PB if we don't need any function of it?

3. Is the software reset needed when power up to configure the resisters?

4. Do we have a document or tools to guide how to configure the resister?

Thanks a lot

Matthew Chen

over 3 years ago

0 David (ASIC) Liu over 3 years ago

TI__Guru**** 177081 points

Matthew

1. Can you please share their schematic?

2. The TFP410 can be configured through pin configuration, they do not need to program it using the I2C register. Are they seeing the clock output if they configure the TFP410 using the pin configuration mode?

3. Can they make sure the HTPLG is driving high?

4. Do they have 50ohm to 3.3V on the scope side when probing the clock output?

Thanks

David

0 Matthew Chen over 3 years ago in reply to David (ASIC) Liu

TI__Intellectual 1400 points

Hi David,

Thank you for your reply.

Customer has already made the PCB board which configure the device by I2C.

Now they can capture the signal after setting the TDIS = 1 in the CTL_1_mode. They wonder to know the amplitude and frequency of the output signal, which can help them to classify their results. I can't find any description about the output signal.

Another question, according to the datasheet, the HTPLG is used for monitoring the hot plug detect signal. If this function is not needed. Why it should be drive high? Will it has any influence on the outputsignal?

Thank you

Matthew