You can see my PoC network in the bottom of the image.
My intention is to send 12V,1A along with this data(DOUT+ and DOUT-).
This 12V ,1A is received at Deserializer side along with the data and is used to power other devices present in the deserializer section.
I gave this schematic to TI AE team for review.The response received is that TI did not tested PoC on thsese devices and they told theoretically it will work.
You can do at your own risk. I decided to take that risk.
DS90UB92xx have internal termination. There should be no R790.
Check intended current load and saturation characteristi of "1000 ohm" ferrite bead. I'm not aware of a 1000R bead with useful current rating. See e.g. biased impedance curve of Fair Rite 1206 600R 1A ferrite bead, it clarifies that 1A rating is a pure DC figure. Ferrite beads of other vendors have similar behaviour, rarely documented, unfortunately.
I expect a separate ground return, e.g. through differential pair shield. If it's not present, you need an additional POC- path with chokes similar to POC+.
DS90UB92xx have internal termination. There should be no R790.
Check intended current load and saturation characteristi of "1000 ohm" ferrite bead. I'm not aware of a 1000R bead with useful current rating. See e.g. biased impedance curve of Fair Rite 1206 600R 1A ferrite bead, it clarifies that 1A rating is a pure DC figure. Ferrite beads of other vendors have similar behaviour, rarely documented, unfortunately.
Besides discussed problem of saturation with DC bias (as expected, your manufacturer doesn't specify it), the impedance in the frequency range of interest (> 500 MHz) is very low.
May I know can I connect multiple ferrite beads in series to improve the impedance.
As per my self study goal of the PoC filter is to make the impedance of the PoC delivery network much higher than the impedance of the 50-ohm transmission line so that the high speed signal edges don't "see" the PoC network.
Coilcraft 4310LC Series wideband bias chokes provide flat bandwidth with high impedance to 6 GHz. They offer low DCR and excellent current handling and are ideal for use in high-current bias Tee applications.
TI POE doc says " 3.1.1 ...The current that this circuit can handle is limited by the ferrite beads at 250 mA."
- 4 times as many FB's in parallel ?? hmm research if this has been done before
I would start with design specs: e.g. then work out what is needed for each part.
DC port s21 = -12dB min over passband design target 15 dB
Do above for V+, V- and also Vcm effects on CMRR
Convert DC port s21 to Z(f) for 50 ohm load.
Compute all L's, Rs Rp within reasonable R/L ratios like 100 to 300 (guestimate), compare FB's for R, R/L, I max over spectrum in spreadsheet
Ensure 12V power sequence is transient protected on low voltage sides.