CSD23382F4: Dimension NG

Cheah,

Thank you for contacting us, I will need to contact some packaging people and will get back to you as soon as possible.

Many thanks

Chris

Cheah,

I have contacting our packaging experts and they have a few questions we would like for your to answer if possible, before we can answer your questions:

1. These features are done at a wafer level so it is unlikely to have different values within the same wafer, in other words all units would fail or pass, unlike the measurements you have given in your table
   1. Could you please provide the lot number or TI lot trace code for the devices you have shown in your table, are they all one lot or different lots? We can then go and check our specific internal data to see if there was an issue.
2. The way you describe the measurement seems to be user dependent and not automated.
   1. If manual was the measurement done only once?
   2. Can you repeat the measurement to see the repeatability of the measurements?
3. We are unable to define the equipment you should use for your own process but can you double check on the calibration and make sure the software and equipment are up to date.
   1. The reason we say this is the equipment you mention, according to the specification, has a resolution of 0.001mm but your numbers report 0.0001mm
   2. We do not know if you have an enhanced version of this equipment capable of 10x better resolution than they specify for the std VMG-450 model.

Many thanks

Hi Chris, 

Sorry for late reply.

1. The lot number for this device is 9827876CL9. They all are in one lot. 

2. We have done the measurement three times. Each measured value is almost the same.

3. The equipment and software that we used are calibrated and up to date. Actually, all the values measured are in 6 decimals number in unit of mm. I think it may because of the software we used able to support the measurement to 6 decimals number.

Hi Cheah,

Chris is out of office today. Thanks for the updated information. Is this dimensional issue causing a problem with assembly of the devices onto the customer's board? We will review and get back to you when Chris returns next week.

Thanks,

John Wallace

TI FET Applications

Hi John,

We have not implement this device onto the board yet as this issue was found during our incoming inspection. The overall size of the device is within the spec however the dimension of footprint is larger than the spec in datasheet. Therefore, we afraid that this dimension NG of footprint would affecting the function of this device if we assembly the devices onto the board, and so I am writing here to seek for advice from Texas Instruments professional technicians. 

Thank you.

Best regards,

Cheah 

Cheah,

I am sorry but we were unable to find this 9827876CL9 in the system, do you have a photo of the shipping label on the box that you could send so we can go and check our manufacturing details. Or any other information you could please provide for this lot.

Thanks

Chris...

Hi Chris,

This is the label for this lot.

Many thanks,

Cheah

Cheah,

Thank you, we will investigate and be back to you ASAP

Chris

Hi Cheah,

Apologies for the delay. We are still waiting on more information from the factory and will update you as soon as we have it.

Thanks,

John

Hi Chris and John,

Any update from the factory?

Thanks,

Cheah

Hi Cheah,

We're still working to get the data. If the customer follows the recommendations for PCB layout and stencil design, they should have no problems placing and soldering these devices onto their PCB. The dimensional variation should not cause any reliability issues. Below is a link to the FemtoFET SMT guidelines. TI has shipped high volumes of these devices and there have been no reported issues due to the dimensional variation of the package. We will update you as soon as we have data to share.

https://www.ti.com/lit/pdf/slra003

Thanks,

John

Hi Chris and John,

It has already been passed 2 weeks. Do you have the data to update and share to us?

Thanks,

Cheah