DS90UA101-Q1: Looking for SerDes for GPIO and I2C

Hello Kazuki,

For the GPIOs do they need to be bi-directional or just unidirectional? How many go one way vs. the other way?

Best Regards,

Casey 

Hello Casey,

Bi-directional is best, but Customer will accept Uni-directional if Bi-directional is difficult.

Customer required 8GPIOs in bi-directional case. So they need up to 8 GPI and 8 GPO in Uni-directional case. However I think we don't have candidates of satisfied the counts of required GPIO. So If you have candidate which has less GPIO support pin than customer requirement, please let me know.

Best regards,

Kazuki Kuramochi

Hello Kazuki,

We don't really have an optimized product for something like this unfortunately. I don't have anything to recommend except for maybe DS90UB949-Q1 + DS90UB948-Q1 for example, but even this solution is not really ideal for just transferring GPIO. 

Hello  Casey,

Thank you for your prompt advice for me.

I understood we have ideal products for this requirement.

Sorry for bothering your but I would like to confirm about below 3 points.

The first, can our SerDes products (ex. DS90UB949-Q1 + DS90UB948-Q1) be used without any signal input other than GPIO and I2C?

Next, In previous E2E thread you explain we must comply the standard if the CSI input type device. Our FPD-link supported several input signal type. For exmaple HDMI, LVDS, LVCMOS, etc... Cannot all devices be used for low frequency input signal(GPIO)?

Last, FPD-link products has GPIO port. However I think GPIO port has 2 type. One type is that propagate input status transition to opposite site GPIO pin, and the other type is that configured GPIO H/L status by I2C.Our portfolio has some devices which has more than 8 port of  I2C controled GPIO.(exDS90UB949 + DS90UB948). However our portfolio don't has device which has more than 5 ports of the first type of GPIOs. Is this understanding correct?

Best regads,

Kazuki Kuramochi

Hello Kazuki,

I think there may have been a misunderstanding. I was trying to say that the FPD Link devices are not ideal for such an application. They are designed primarily for transferring high speed video data, not for transferring many GPIO. 

Theoretically our devices can be used for transferring GPIO data without any video data as long as you provide a PCLK to set the link speed. Then you would simply just only the GPIO pins and not the video interface pins. But the number of available GPIOs is very limited as you mentioned in your above post. Some GPIOs can be assigned forward or backwards direction but they can not be bidirectional. 

Best Regards,

Casey 

Hello Casey,

I understand that FPD Link is not designed for this application. However I would like to confirm about it  has the probability of being able to use for this application. I think CSI input and AC coupled devices can not be used for this application. But I think it remain probability of that if device's video port accept low frequency single-ended input.

If video port cannot accept it, I will introduce the usage of using GPIO pin without VIdeo input. Of course I agree this usage is overqualified to FPD-Link. However we don't have other candidates and customer don't concern about price in this time.

Best regards,

Kazuki Kuramochi 

Hello Casey,

I appreciate your kindly explanation and strong support.

I will introduce DS90UB933-Q1 + DS90UB934-Q1 solution to customer.

Thank you and best regards,

Kazuki KUramochi