cancel
Showing results for 
Search instead for 
Did you mean: 

Dual STUSB4710 Power Management

YunusBasegmez
Associate II

I am designing a usb type-c charger. 

I want to use 2 microcontroller and 2 STUSB4710.

Type-C Output will be 20V 3.35A 67W.

I want to do power management between these USB Type-C outputs.

I have questions. Can you please answer them?

 

1. Are there any I2C command to close the output pmosfets with STUSB4710?

2. Can microcontroller reduce the output current capabilities of STUSB4710 while a device connected to USB Type-C sinking some current. For example,

  • Default output contract is 20V 2.25A
  • Send I2C command to STUSB4710 and change the output capabilities to 20V 3A.
  • Output contract is now 20V 3A.
  • Attach a usb device which sinking 20V 3A power and start consume 60W.
  • Send I2C command to STUSB4710 and change the output capabilities to 9V 2.25A.
  • STUSB4710 send message over CC communications.
  • Sink device reduce power consumption to 9V 2.25A.
  • Is the scenario possible? If there is a problem, can you correct it?

3. Is there any other way to reduce sinking current of the connected usb device?

4. STUSB4710 supports 20V 5A. But Vconn is not supported with STUSB4710. Is there a standard incompatibility?

5. Is 20V 3.35A type-C output possible with STUSB4710?

6. I have found this post https://community.st.com/t5/interface-and-connectivity-ics/stusb4700-4710-i2c-register-details/td-p/234334. But I did not find any clear guidelines(step by step) for changing register and effects of it. Also some registers contained TBD values.

10 REPLIES 10
MKN
Associate II

Hi,
we are using the STSW-STUSB006 I2C Lib whose only pupose is the programming of the STUSB4761 with an own MCU. What else does ST think what the Customers will do with it?

The datasheet explicit describes multiple reprogramming and what to do that the new configuration will take effect. Definitely not 'write once'
I assume the NVM is a normal flash with 10.000 to 100.000 write cycles.
Please clarify the maximum allowed write cycles.

It would be better if ST clearly says what this Chip can do and what not.
Not this information obscurity of unspoked things to 'protect' the customer from his own decisions he made with much to less informations.

 

Best Regards

Michael