2x MPQ8875A in parallel using I2C bus

Hi, We are planning to integrate 2 units of MPQ8875A Buck-Boost in the same PCB with these features:
-) Both regulators will have the same input voltage (8,5V-36V). Each one will have its corresponding filters.
-) One MPQ8875A will be used for getting 12V and the other one 24V.
-) Both will share the same I2C bus.

I have the following doubts:
-) SYNC pin: Can we connect the pin SYNC between the two converters for haveing synchronization in the switching frequency?
-) OTP: Can we save the I2C address in the OTP? For saving the I2C address and avoid conflicts between the 2 converters we can use the ENABLE pin.
-) The correct way to modify OTP is using the I2C bus? If not, which tool is recommended for saving OTP in production?
-) Can we test the OTP modification with the evaluation board?

Thanks in advance for your support.

Hello,

Yes, you can connect two devices to the same switching frequency on the SYNC pin. Refer to bottom of page 37 of datasheet.
For this device, you can permanently save a new configuration including a different address by writing a page. There are limited number of pages which can be checked through bit 6 and 7 of 0Fh register. An easy way to do this is utilizing our Virtual Bench Pro GUI. You can test this out with an evaluation board.
Hope this clears any confusion.

Best Regards,
Yu

Hi. Thank you for the information.
Another question about this converter. How can I calculate the external RC compensation network tied between the PVOUT and VFB (page 61 of datasheet). I have not watch information about it.
Best Regards.

Hello,

Check out this application note. Hope this helps.
Evaluating the Transient Performance of Buck Regulators with an Integrated Compensation Network | Article | MPS (monolithicpower.com)

Best Regards,
Yu

Hi!
Regarding to the I2C interface, I have read this comment:
“The I2C interface uses VCC as its power source.”
I have not watched in datasheet the minimum voltage to accept a “1”, and therefore I cannot know if the pull-up resistor on SDA and SCL can be connected to 3,3V to avoid introduce a Voltage Level Shifter in our design.
Is it possible to connect the pull-ups to 3,3V?
Regards.

Hello,

SDA/SCL input logic high is 1.5V. Yes, pulling it up to 3.3V should be fine.

Best Regards,
Yu