Magic4g 夢幻國度的虛幻世界

Subject

[David][BT]All references to 2.9 V supply were changed to 3.0 V supply



Description

Dear Qualcomm Team,
Revealing the document of 80-WL300-1_F_WCN3660 Wireless Connectivity IC Device Specification.pdf in which all references to 2.9 V supply were changed to 3.0 V supply throughout the document from F revision.
Do you happen to be able to explain us the reason why?
We are a little concern for it, since we had defined VDD_BT_TXRF_2P9 instead of VDD_BT_TXRF_3P0 in our WCN3660-wise circuit scheme.
What difference would it result in if we happen to make use of VDD_BT_TXRF_2P9 instead of VDD_BT_TXRF_3P0?

BR
David

Comment



Created By: Rossi Hung (9/6/2012 12:26 AM)
Hi David,

For MSM8930 platform, please refer to latest MSM8930 baseband schematic 80-N7379-42, which is using VREG_L10 for WCN3660 3.0V power rail supply.
It should be the same case with MSM8960 as mentioned in previous case comment.

The most conservative way is always follow the latest platform schematic, for MSM8930+WCN3660 please use 80-N7379-42 and 80-N1622-44.

Regards,
Rossi.




Created By: David Lan (9/5/2012 8:07 PM)
Hi Rossi,
Thank you for your prompt responding.
Citing the schematic, it shows MSM8227 & PM8038 in circuit diagram, yet our BSP is named MSM8960.
Reveal the page52 of 80-N7694-21_A_PM8038 POWER MANAGEMENT TRAINING SLIDES.pdf in which Function L10 with default voltage 2.9V of specified range 2.6~3.05V, it is programmable and expected using on WCN hence it should be able to offer WCN3660 the stable working voltage for its output power, right?
By the way, Should SW set L10 to 3.0V instead of default voltage?
BR
David




Created By: Rossi Hung (9/5/2012 2:24 AM)
Hi David,

It should be entire VDD_2.9V net name change and corresponding configuration at PM8921 VREG_L10 has been done in MSM8960 SW release already.

The reason to update 2.9V to 3.0V is to obtain better WLAN TX EVM and it was also verified with MSM8960 reference design MTP as well, thus we updated this change in the device specification since 80-WL300-1 rev. F.

The latest WCN3660 device specification is 80-WL300-1 rev.K and the latest WCN3660 reference schematic is 80-N1622-44 rev.J

Please always follow the latest schematic in your design to prevent any unexpected problems.

Regards,
Rossi.