TPS659112 + DM8168 question

Hi,

You can use VDD1. Please refer the notes in the document. CVDDC requireemnt may be >1.5A. In this case you will need an external DCDC.

TPS51116 is used for DDR. There is no LDO that can satisfy the DDR current requireemnts.

Hope this helps.

Thanks, this clarified the things.

What about using one of the LDOs to supply 0.9V USB? What is the purpose of the TPS7101 ? If the current is an issue, can I connect 2 LDOs in parallel?

Greg

Hello 

Long Time ago I am trying to have more accurate information about the TPS659112 like how to obtain the full datasheet,no one can give an answer, may be  I should design my power rail in a more conventional way.

Please could someone direct me to wright person to get  what I am looking for ,I have the feeling that I am wasting my time.

Regards

Hi

I've got the datasheet immediately after I contacted the technical suport.

Greg

Thanks I already ask the technical support  but I have receive no answer, and why the full data sheet of this part is hidden I like build design on parts that have information widely

open ,just in case Ti decide to change their mind,and not get stuck in the middle of design

Regards

Eric

Please contact me directly by email. f-stel@ti.com

Hello fabian I am still waiting you answer

Regards

Eric

PLease close this topic and contact me directly by mail.

Hello Grzegorz

I have the same issue,did you get the answers to your question about using an external LDO to power 0V9 rail,

your right right, why using  an external LDO,when VDD2 provide  enough power to  supply 0V9 USB .

Me to I want to simplify as much as possible the power rail,But the truth is, with all different information I have about this chipset I am not so sure what can  really be  done.

Rgds 

Eric GUARD

I decided to use TPS71701 LDO as an option, during debugging I will decide to mount it or not.

Greg

Hello!

I am testing a prototype of board based on DM8168. We are using PMIC TPS659112A.

During tests I faced a problem: PMIC correctly gives out demanded sequence of voltages, however right after it it goes to reset and so proceeds in an infinite cycle. Cycle period is 30ms.

PWRON pin is floating

PWRDN pin is floating

BOOT1 pin pulled up to VRTC with resistor 20k

PWRHOLD pin is floating

We trying with pin SLEEP: leave floating, pulling down to GND, pulling up to 3V3, however it didn't give any effect.

Between pins F8 and F7 (OSC32KIN and OSC32KOUT) placed an quartz resonator 32768Hz.

Somebody can help me to understand in what direction to look for a problem?

Thank you very much!

can you please try to pullup PWRHOLD pin as soon as the device boots up?

Please let me know if this issue is alredy close we can close this post.

Hi Sir,

I had meet the same issue when I used DM8168+TPS659112 now,  It seems that TPS659112 is during power on -off  cycles.   I had test that the parts of power outputs and signal  will been OK (VDD1,VDD2,VIO,LDOs,RTS outputs...NRESPWRON) , when I had removed  DCDC Ctrl MOS,(1.0V AVS no output ).

So, I want to known that which causes will cause the TPS659112A to re-boot by cycles. (the boot  cycle was about  

30ms )which similar to the TPS659112A power up timing cycyle) 

I had changed the Rtrip to 10K from 39K , it seems that no affect to the issue. 

many thanks !

I had try to pullup PWRHOLD. it seems no useful.  many thanks for any boday can give useful suggestions.!

Hi Jimmy,

My only question here is what is the purpose of removing this MOS?

Controller is the part of the power up sequnce. If if the mosfet is not there it will not work.