Hi,
We are using a PTN5110NHQ in a battery powered video inspection instrument charging over USB-C. In general this is working fine. However in a recent board release we slightly changed our design and we now have a problem that it is not charging when the battery is dead.
The new board design now has the PTN5110NHQ's VDD power line come up a short time after VBUS. The datasheet and TCPC spec. isn't clear on how dead battery mode actually works, but from our observations we believe the PTN5110NHQ goes into dead battery mode, setting EN_SNK1, if it sees VDD low in the VBUS 15ms de-bounce period and as our VDD now comes up quicker than this the PTN5110NHQ enters a passive mode. Is this correct ?
Assuming this is correct, the datasheet mentions a PTN5110NDHQ part suggesting this starts in SINK mode. Would this fix our issue ?
If it does, we see that the PTN5110NDHQ is not available from anywhere ?
However, we do note in a document, that the PTN5110 has NVM that is configured in the factory so that the part could be configured as a PTN5110NDHQ.
Is it possible for us to to write to the NVM to configure our chips as PTN5110NDHQ devices ?
And if so how ?
Terry
Thanks, but as stated we are already using the PTN5110NHQ. The issue is that with our production boards the VDD supply is coming up only shortly after VBUS. It is not clear in the PTN5110 datasheet, but reading between the lines, I believe it will only enter dead battery SINK mode if VDD is low at 15ms after VBUS becomes present, which is quite a long time. is this actually the case ?
For a next board iteration, we can look at ways of achieving that, but for now we were hoping that there was a chip that would always enter sink mode on power up as the PTN5110NDHQ sounds like it does, however that chip is obsolete.
The AN12137 document states: "The power-on or default register settings are programmed at the factory into the non-volatile flash memory Multi-Time Programmable (MTP) inside the PTN5110N. These preprogrammed parameters determine the initial behavior of the PTN5110N, e.g., the PTN5110N can behave as Type-C DFP, UFP, or DRP upon power up."
This suggests it is possible to program the default power-up register settings inside the PTN5110N. We are unsure if this is physically possible with the device in-circuit, but if so all we would need is information from NXP on how to do this and it would fix our issue.
Hi Terry,
unfortunately the NVM cannot be changed by any customer. This is an NXP property. So you can solve the issue on PTN5110NHQ (sorry I missed, that you are already using it) or you can buy what is left of the PTN5110DNHQ (no more produced).
I apologize for inconvenience.
With Best Regards,
Jozef
I also notice on the sites listed above the PTN5110NDHQ part is marked as obsolete. Is that the case ?
Hi Terry,
unfortunately no, to change the internal NVM is not possible. I have found, that our authorized distributors Rochester electronics and Digikey have the PTN5110NDHQ components in stock.
https://www.rocelec.com/part/01t4w00000PPyO5AAL-PTN5110NDHQZ
https://www.digikey.com/en/products/detail/rochester-electronics-llc/PTN5110NDHQZ/18449948
With Best Regards,
Jozef
Thanks for the info.
Do you think that the PTN5110NDHQ would fix our issues with dead battery mode where the VDD is powered shortly after VDD ? Ie the PTN5110NDHQ would, by default (no i2C registers touched), set the EN_SNK1 line high to enable the external VBUS to system load switch when VBUS is powered by an external USB-C charger ?
There are no details in the manual as to how the PTN5110NDHQ option actually works.
Hi Terry,
yes, the SNK role at start up handles the dead battery condition.
The PTN5110NDHQ is indeed obsolete. Please consider then the PTN5110NHQ, which is in Active stage of life. Many of our authorized distributors have the PTN5110NHQ in stock.
With Best Regards,
Jozef
For others information, we tried the PTN5110NDHQ in our system and it does not appear to go info full Sink mode on POR. At least it does not appear to raise its EN_SINK line high at POR when both VBUS and VDD go high almost together.
I'm not sure what this variant actually does differently to the normal variant as the datasheet is very limited in content on this.