TPS25750: About configure the 0x33 TX_SINK_CAPS Register

- What's the value of "Higher capability" in the Bit 28  of the first PDO? 0 or 1?

- What is the value of the Bit 25 and Bit 29  of the first PDO? 0 or 1? 

Are you using GUI for this? 

5V PDO is necessary, besides that you can have any HV PDOs <7.

Hello Ghouse,

Thank you very much for your reply.

We don't use the GUI, we want to configure the PD controller as soon as the device start up by a MCU.

The eeprom which was connected to the I2Cm interface can be saved for we have no space on the PCBA, we are designing a very small device.

Actually, the EVM board used a MCU to communicate with PC firstly, and then to configure the PD controller via the I2Cs interface by the MCU.

The GUI is supplied for users to program in an audio-visual way. The background procedure is also program in the EC (MCU) and configured the register by the GUI. That's easier to start, but not the most optimized ways for appling.

So to configure the PD controller in the APP through the MCU instead of the GUI is possible, as well as the way like other TI's PD controllers and chargers.

My question is that some bits for the R/W registers in the TRM, which are described not so clear, maybe for it is really a new PD controller, like I marked in the photos attached.

To configure the PD controller use an EC directly is much more convenient and perfect than use a GUI.

Actually, many users really don't like the GUI, for which need much additional operations, and it is also not an economic solution, unless they only design an sample adapter only for fast charging, then that is a good way.

So that is the reason why I ask the details for description of the registers.

Best Regrds,

Matt

If I only want to design a SINK , which ask for 15V, 3A(max. 45W) from a Source, I think I only need to select one PDO from the 7 PDOs?

Which PDO can be selected? PDO3 or anyone else?

If I selected one PDO in the 7 PDOs, how to handle the others?

Thanks,

show below,

Until now, most of the doubt has been resolved. Many thanks. Left these key rpoblems. Please give me a favor. Waiting for replies. Thanks.

Hi Matt,

I would still recommend using the GUI to generate the binary file which you can use to program the PD controller with via EC. This way all of the registers can be configured easily. Also, this GUI would only be necessary for setting the desired configurations for the end application, it would not be needed for consumers to reprogram the PD controller.

For a Sink device, you will just need to support Sink PDOs that you would require and the device on the other end (Source) would need to select the highest sink PDO that it can support and the 2 PD controllers will negotiate a valid contract and the others will still remain for new negotiations if another device is connected or the current contract is disconnected. Was this your question regarding the 7 PDOs?

You can access the GUI here and you will see it is just a series of questions for your preference and is not very complicated: https://dev.ti.com/gallery/view/1769824/TPS25750_Application_Customization_Tool/ver/7.0.2/

Thank you,

Hari

H Hari,

Thanks a lot for your reply, really!

- For the PDO:

 I know the two PD controller will negotiate, but the premise is must to configure them correctly in advance.

My question is that if i want a fixed 15W, 3A SINK, how to configure the PDO? How to do the actual operating?

The first PDO(POD1) is necessary, another PDO can be selected which one? PDO2 or PDO3? or another one? Because there are 7 PDOs. 

Suppose, if i select PDO2, how to treat and handle the other 5 PDOs? To configeure all bytes to 0x00 for them? or whatever.

The TRM must tell the user how to operate for each bit, if not it dosen't make sense. Like the table below for some bits are not so clear. eg: the Bit 25 and Bit 29  of the first PDO? etc...

- For use GUI or not, this topic must be combined with what products will be developed. Some fit, some unfit.

For products nowadays, to use the Type C PD for power on and transmitting data is only a part of the functions, so to configure the PD controller also will be a part of the firmware for the devices. Since there are a MCU in the system, why not use the MCU to configure it, but use an EEPROM additionally? That is the cost control consideration.

I mean to add the code for configure the PD controller in the software for the device, actually only need write the bits of the registers for PD controller when initialize the device when power on and during start up, that will avoid to consider how to load the binary from the GUI to the flash of MCU in advance.

If we don't use an EEPROM, it bill difficult to use the GUI. GUI only can resolve a small part of requirements.

I guess more and more customers have this need later.

Sorry, I'm not sure if it's clear from the view of users and mass production.

Thanks,

Matt

So, could somebody, who can guide me to configure PDO? Thanks a lot!

I Configured the Table 3-23. 0x33 TX Sink Capabilities Register as below:

- Only config 2 PDOs, PDO 1#(5V, 1A). PDO 2#(15V, 3A). 

Question:

1, About the values of the bits of invalid PDOs: I set all the bits of invalid PDOs, PDO3#~PDO7#,   to "0", are these sets right, or not?

2, About the units and values for the Voltage and Operational Current: I set the Voltage and Operational Current with the unit of 'V' and 'A', and entered to correasponding bits with the values, what like i did are right or wrong?

To configure this register is the key steps for the PD controller configuration.

Please do help to do these confirmation.

Thanks,

Matt

- I think only write the needful bytes for the Wr registers, keep the other bits' defaults.

- So only the unit for vpltage and current are key problems.

  For current, 10mA, 50mA,100mA, or others?

  For voltage, 10mV,50mA or 100mV, or others?

Thanks,

Matt

Who can help to confirm? 

Hi Hari,

Thank you very much.

So my understanding is that for this PD controller, which is not fit for the design that the customer want to configure it with an EC with self developed software, and without an EEPROM and GUI binary file as well, right?

For if we use the binary which created from GUI, for there are also additional components and programming steps, and also wasted more PCB space, as well as the produce time, which we really care.

So if we want to configure the PD controller with EC, and develop software by ourselves, it's better to select another PD controller, right?

Could you please recommend one from TI, which can meet our requirement?

Thanks,

Matt

Hi Hari,

If i want to configure/initializing the PD controller with an EC, don't prefer to an EEPROM and GUI binary, could you please let me know is that suitable if I select PD controller TPS25981 for using?

So far I really scare about to selected a PD controller without ask any support from TI. Like TPS25750 west me much time, but not met the requirements of project finally.

What we care are, to minimum PCB size (save parts ASAP, so don't need the EEPROM) , initializing the PD controller as soon as power on for the EC(MCU). That means we prefer to develop software by ourselves.

We want to supply power 15V 3A for Motor driver DRV3806 and charger BQ24172.

What do you think about TPS25981? Is this one suitable?

Thanks,

Best Regards,

Matt

HI Hari，

i think maybe I'm misunderstanding for TPS25750D, from part selection view, TPS25750 is the best choice.

I'm trying to configure it with the low region binary file according to the supporting from your college Chuck.

Maybe i can configure with EC for TPS25750.

Thanks a lot,

Matt

Hi Matt,

I think you could but I will need to check on this with Chuck first.

Thank you,

Hari

That's great! Thanks a lot.

Matt,

I apologize, but this issue seems to have dropped between Me and Hari.

Is there something we can still do to help?

Regards,

Chuck

Sorry, I'm not sure, I will ask support later for this case.

Right now, I'm focus on the Patch Bundle issues.

Thanks,

Best Regards,

Matt,

I will hold this case open on my end.  Just reply when you need support