AFE7225: LVDS ADC Pin Name/Description Polarity Clarification

Wayne Cox

Part Number: AFE7225

For the DAC LVDS signals, that are labeled with non-reused CMOS names in Table 2-2 (why change some but not all?), the pin name's indicated polarity matches with the desription, but the ADC LVDS lines appear to have reversed polarity from name to description as highlighted.

over 4 years ago

0 Vijayendra Varma Siddamsetty over 4 years ago

TI__Genius 10855 points

Hi Wayne Cox,

In Table 2-2 DAC LVDS signal names should ideally be updated to LVDS names as in figure 2-2. This is just an oversight in the datasheet.

Regarding the ADC lines polarity, table is incorrect. i.e. for example, pin 42 is named as ADCB_DATA_1N, it is the negative pin and pin 43 named as ADCB_DATA_1P is positive though the Table 2-2 suggests otherwise.

Regards,

Vijay

0 Wayne Cox over 4 years ago in reply to Vijayendra Varma Siddamsetty

Prodigy 10 points

To paraphrase: The Figure 2-2 pin name is correct in general excepting the polarity indication (xxxx_xN or xxxx_xP) in which case the Table 2-2 polarity in the description is correct despite it directly contradicting the Figure 2-2 naming scheme

0 Vijayendra Varma Siddamsetty over 4 years ago in reply to Wayne Cox

TI__Genius 10855 points

Hi Wayne Cox,

Yes. I think the description is correct though pin names suggest otherwise.

I'm checking the pin connections on AFE7225EVM; TSW1400EVM and if there's any inversion in software to confirm this. Will update you in a day or two.

Regards,

Vijay

0 Vijayendra Varma Siddamsetty over 4 years ago in reply to Vijayendra Varma Siddamsetty

TI__Genius 10855 points

Hi Wayne Cox,

Sorry for the delay in my response. I checked with the design team and found that polarity suggested by pin names is correct. Description in Table 2-2 is incorrect.

Regards,

Vijay

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AFE7225: LVDS ADC Pin Name/Description Polarity Clarification