CC2560: CC2560B and PAN1325B module power supply problem

Andrea Verdecchia

Part Number: CC2560

I'm trying to use the PAN1325B module that is based on the CC2560B. I don't understand the "Device Power Supply" section in the datasheet, where are explained three operating modes based on the connection between CL1.5_LDO_IN, MLDO_IN and MLDO_OUT.

I think that the CL1.5_LDO_IN is for the antenna alimentation, but what is the function of the MLDO_IN and MLDO_OUT? In the "Mixed DC2DC-VBAT system" option in the picture why they are connected toghether?

Can anyone explain me these three configurations?

over 8 years ago

0 YiKai Chen over 8 years ago

Guru 735685 points

I suggest you to post CC2560 issue to Dual Mode Bluetooth E2E forum at e2e.ti.com/.../

0 Andrea Verdecchia over 8 years ago in reply to YiKai Chen

Prodigy 120 points

I tried but, when I entered the device name (CC2560), the site has redirected me to the other forum. I don't know why.

0 YiKai Chen over 8 years ago in reply to Andrea Verdecchia

Guru 735685 points

Anyway, system moderator already move your post to Dual Mode Bluetooth E2E forum now.

0 Vihang Parmar over 8 years ago

TI__Mastermind 29311 points

Hi,

Andrea Verdecchia said:

I think that the CL1.5_LDO_IN is for the antenna alimentation, but what is the function of the MLDO_IN and MLDO_OUT?

MLDO_IN and MLDO_OUT refer to the Main LDO (internal to the CC256x). As mentioned in the CC256x datasheet, the MLDO_OUT value would be 1.8V nominal.

Andrea Verdecchia said:

In the "Mixed DC2DC-VBAT system" option in the picture why they are connected toghether?

In the Full-DC2DC or Mixed DC2DC-VBAT, VDDIN connected to the MLDO_IN is (1.7V to 1.98V). Thus, MLDO_OUT is connected to MLDO_IN to bypass the internal LDO. In the full VBAT system, the MLDO_IN is higher (2.2V to 4.8V). Thus, the internal LDO is active and the MLDO_OUT will be 1.8V.

Best regards,

Vihang

0 Andrea Verdecchia over 8 years ago in reply to Vihang Parmar

Prodigy 120 points

So the MLDO_OUT is a 1.8V power source in addition to the functionalities of the CC256x which can to be used for general purpose, like feed the VDD_IO input of the same IC (MLDO_OUT connected to VDD_IO)?

0 Vihang Parmar over 8 years ago in reply to Andrea Verdecchia

TI__Mastermind 29311 points

MLDO_OUT is just there as a test point if you are using MLDO. It cannot be used as an LDO out to power other things. Also, it cannot be used to feed into the VDD_IO.

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CC2560: CC2560B and PAN1325B module power supply problem