No USB or Battery Power

[Beko]

Hi,

We are designing a board where USB or Battery Backup power is not required. Per recommendations in your application notes we are pulling the VIN_USB pins to GND but we are following the suggestions in TI Application Note SLVA901 (http://www.ti.com/lit/an/slva901/slva901.pdf) and instead of leaving the VIN_BAT and PMIC_BAT_SENSE connected but floating, we are connecting them to GND with a 1K resistor. (See attached image) Do you think following the TI application note would create any issues or help us in any way? Thanks.

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[Neeraj Dantu]

Beko,

We don’t expect any issues with connecting VIN_BAT and PMIC_BAT_SENSE to GND via 1K resistor.

Please let us know if you have more questions.

Best,

Neeraj

[Beko]

Thank you Neeraj.

[Beko]

Hi Neeraj,

I just wanted to follow-up on this topic. We did make a new board with VIN_BAT and PMIC_BAT_SENSE to GND via 1K resistor as the TI Application Note suggested and you said you don’t expect issues but NOPE. It did not work, we had no signs of operation from the OSD335x C-SiP. As soon as we have removed the 1K resistor and kept the ends floating and VOILA, it started working. I guess we should have followed your recommendations instead of TIs. 🙂

Just writing this for the record and maybe you may want to further investigate this.

Regards,

Beko

[Neeraj Dantu]

Beko,

Thanks for the follow up. It is interesting that the TI recommendation did not work. We will investigate. Glad you are able to bring up your design successfully! Please let us know if you have any more questions.

Best,

Neeraj

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