Hi,
I am using MP2770 to interface it with USBPD using STM32G4. I am reading the Input voltage register 0x11. I have not connected any adaptor on VIN pin, still I am getting some voltage value in 11h register. I have verified VIN voltage using a multimeter, it is showing 0V.
Please check the attached screenshot. See data0 (11h), data1 (12h), data2 (13h), data3 (18h) values.
Please help,
Thanks in advance…
Hello 16uec083,
When you plug something in do you get expected voltages being read from this register?
Do you have another device with 0x96 device address? I believe the following register corresponds to the valid i2c addresses. Let me know if your issues persist using these.
Yes, I am getting expected value when I connect some power source but when I unplugged it, some value still there in the register. Also, am able to read other registers correctly.
I have a single device connected in I2C.
Also, Am using default I2C address i. e. 4Bh. STs hal library support I2C address as (Address << 1), that’s how it becomes 0x96.
Thanks for the update. I will follow up when I have more information.
Hello,
Can you try making ADC_RATE = 1 and ADC_START=1? Let me know how this works out.
Hi eduardo,
While debugging this issue on the hardware side, I found BAT and VSYS pins were shorted internally. Maybe because of this, I was getting some voltages on VIN. But I don’t how these pins were shorted. I replaced the IC with a new one, and it is giving correct values on VIN pin.
Now, after replacing it, I am observing a weird behavior. I am setting CONFIG register for boost mode in the default VBST setting. I am getting 4.5V on VIN pin using multimeter, and after sometime (10-20 sec), voltage becomes 0 and at the same time CONFIG register value changes to charge mode. I have not connected any load on VIN pin.
Why this register value changed itself?
Hello 16uec083 can you share your schematic and layout? Can you give me register values for 0Eh, 0Fh, and 10h please.
Hi eduardo,
I am getting following values:
0Eh – 10001001
0Fh – 10100
10h – 1110000
I have not connected any load on VSYS and VIN.
It seems like after getting some values in these registers, all other registers are set to default values. I tried setting other registers like VBST but after getting fault values, this register also set to default automatically.
Initial voltage on VPMID and VIN pin is around 4.5V, after fault VIN becomes 0V and VPMID is 3.7V.
Here is snap of layout and snap–
I checked that BST cap is placed on pin 3 (SW), which is a little far from inductor. Then I manually mounted near to inductor, still no change in the operation.
Hello,
The faults shown in 10h are
I’ll send this to our team and see what they come back with.
In the meantime, can you probe the Vin and Vsys and provide captures. Can you also test what happens when something is plugged into the Vsys and Vin. Does this behavior continue?
Hi,
Behaviour is the same with and without load, load turns off automatically after 15-20 sec.
Here are the plots;
While probing the VSYS pin, I mistakenly shorted the IC 
Will replace the IC and share with you soon.
Hi eduardo,
Have you got any solution for it?
Hi @eduardo.FAE ,
Still waiting for your response.
Thanks for providing this. From the images there does seem to be a sharp drop in the Voltage. Which could point to a sharp increase in current. You previously had OC faults for IN and SYS show up. Do you have captures of noload condition and the shutdown that is experienced. Could you also provide the same Vsys captures. Can you share your full list I2C commands used to configure this device.
Hello,
Please fill this out for further assistance Contact MPS - Contact
Hi,
Here are the captures for no load:
There is no change in VSYS waveform
Here are the register settings:
IC Address and Boost LS-FET Peak Current Limit (19h) – 0x1f
Boost Current Limit (05h) – 0x3f
Charge Configuration and Input Current Limit (08h) – 0x0f
When I disable the Q2 FET, still I am getting Vsys voltage, I tried setting Q2 enable, still no change in boost behaviour WHY SO?
Any update on this please!
I have followed up with our team to contact you