When to enable the dead battery mode for UCPD, there are a battery pack in system?

[Lmatt.11]

Hello Sirs,

I am developing a project, a portable device, which attached a 12.6 V battery pack. The device can be power on both the battery pack and a 100W PD adapter. There are a power management IC to organize and select the power path dynamically.

Right now, every works fine, except the orientation of the type C detection.
If attached the battery(not dead state), only one orientation works normally, i.o. out put 20V, another orientation only output 5V, that is the default PDO value. It seems only CC1 or CC2 can be detected.

But if i removed the battery pack, two orientation both works normally. CC1/CC2 can be detected clearly corresponding to each orientation which I changed, plug/ unplug with a different orientation for the type C.

My question is that when there are a battery(or battery pack) attached, is that dead battery signal must be enable? The problem What I met is related with the i have not enable the dead battery signal?

Could somebody have experience on this topic?

Thank you very much!

Matt

[Nicolas P.]

Hello @Lmatt.11 

Can you share a bit of details ? A part of schematics ? Do you use TCPP01 chips ?

Nicolas

[HFISTM]

Hello,

Your battery pack should not interfere with cable orientation. Can you share your schematics ?

Also, could you also please share your trace when you successfully have 20V and when you only have 5V in the other cable orientation. Pleas refer to wiki for sharing the trace.

The dead battery signal you mentioned needs a specific wiring described in the reference manual. We could check the configuration in your schematics.

Thanks & regards

[Lmatt.11]

@Nicolas P. ,

Yes, I use TCPP01-M12, my appliction nearly the same as the following reccommended schematic.

Torromow i will upload my schematic and trace.

thank you very much for your fast reply.

Matt

[Lmatt.11]

@HFISTM ，

Thanks a lot for your rapid reply, my schematic is nearly the same as the reccomended one in the datasheet of TCPP01, I will upload my trace torromow and mine schematic diagram. 

Matt

[Lmatt.11]

@Nicolas P. 

Please find my schematic enclosed.thanks.

Matt

[Lmatt.11]

@HFISTM ,

Please find my schmatic enclosed.

Thanks，

Matt

[MROUV.1]

Hello Matt,

Nicolas shared your case.

The schematic is very close to X-NUCLEO-SNK1M1 with an additional blocking diode (D_513) to block leakage voltage coming from the power management IC.

Without battery and at type-C cable disconnect, all the system is reset. At attach, the entire system reset properly from scratch.

With not depleted battery and at type-C cable disconnect, the leakage voltage coming from the power management IC lets a residual voltage on Vbus_S. The type-C state machine is stuck waiting for a voltage lower than Vbus_safe_0V. An additional attach process cannot be completed, and the previous CC line remain active. The Vbus_safe is sensed by ADC_IN6 ‘VBUS_PD_VSENSE’ but I do not locate to resistor divider on the shared schematics.

Based on that assumption, a solution could be :

• Connect anode of blocking diode (D_513) to source of N-MOSFET (T_500) or
• Use dual N-MOSFET with common source and common gate like used in X-NUCLEO-DRP1M1

Let us know if that solve the case.

I recommend updating R_503 from 619Ω to 536Ω to remain compatible with some not compliant adapters.

Best regards,

Mathieu

[Lmatt.11]

@MROUV.1 ,

thank you very much for your reply.

I ordered a X-NUCLEO-USBPDM1 and developed according to this evaluated board.

I will check according to your suggestions.

thanks，

Matt 

[Lmatt.11]

@HFISTM ,

Thank you for your info..

Does the dead battery mode enable or disable status will effect the orientation of the PD type C negotiation?

BR,

Matt