EVAL- SCS001V1: Doubts regarding type of source, configuration and output.

[AshutoshK]

Hello There!

I have bought EVAL- SCS001V1 sink device for my application in which I need the output as 12V/2A from the mentioned sink device. I came across below problems and I seek help on it.

1) Problem related to STSW-STUSB002 GUI version 2.0.

The first problem is with the GUI version 2.0 as specified. When I made hardware connections as mentioned in the quick start document and I tried to connect the Nucleo- F072RB with the GUI 2.0, I got an error which says " The Parameter is Incorrect". and I'm unable to connect the hardware with the GUI 2.0.

I have resolved this issue by using the previous version ( STSW-STUSB002 GUI 1.09 ). So my hardware got detected in this version and I was able to program or write the NVM successfully. In the Connection Status of the GUI 1.09 it showed that " OK STUSB4500_L  Detected (COM19), at address 0x28 (I2C bus 1)" sharing image below.

2) Problem related to the usage of the source device and selecting desired PDO's.

Currently I'm using the 65W mobile phone charger as the source device. I was not aware of the charging technology it was using. I was not able to switch the PDO profiles at the output. I was getting constant output 5V whereas the required is 12V. So if I'm not wrong the source must be USB PD technology support.

I need help on the available sources which I can use. And how can I select the desired PDO from configured PDO's in NVM to get the desired output 12V/2Amps.

 

[AshutoshK]

Hello Nathalie

Thankyou for the details, I'm getting 12V as a output at the output of the sink device. But there is one issue I'm getting, when I power ON the source at the very first time I can't able to get the 12V output at sink device output. The led on sink device blinks and it goes in off state. After sometime I need to power OFF the source and power ON it again then I get the output at the sink device as 12V. I dont know why this is happening please help on this.

Best Regards

[NBALL]

Hello

Would it be possible to get some oscilloscope capture of VBUS, Vsink, CC1 & CC2 please ?
I think that the application creates an inrush on power path closure when it is closed the 1st time. 2nd time, application capacitor might be not fully discharge so that inrush is less and it can start.

Can you please extend to 20% UVLO for 12V PDO (it is by default 10%)?

Best regards

Nathalie

[AshutoshK]

Hello Nathalie,

Please refer above reply

Best Regards,

[AshutoshK]

Hello Nathalie,

Okay, FYI currently UVLO is set to 20% while the above issue is happening. As suggested by you I'll get the waveforms and update you

Here is the oscilloscope capture of issue.

 

Blue: VBUS = 5V

Yellow: CC2 = Around 2V

Pink: VSNK = 2V spike

In the above case as we could see that the FET is not turning ON. On VBUS there is 5V constant and on VSNK there is just a spike and no voltage where as CC1 is constant around 2V.

Below is the capture of Normal Condition waveform

Blue: CC2 =1.7V 

Yellow: VBUS = 12V

Pink: VSNK = 12V

Please not No Load is connected to the VSNK in both the conditions.

[AshutoshK]

Hello Nathalie,

I am using the 35W source having profiles 5V, 9V, 12V, 15V and 20V. The problem is I'm not able to select the 15V and 20V profiles. It works fine while selecting 5V, 9V and 12V profiles. I'm not able to understand the reason I have tried various values of current and also tried lower and upper voltage tolerances.

Kindly help on this. 

[NBALL]

Hello

STUSB4500 has 3 PDOs.
I guess that when you want to select 15V and 20V, you have suppressed 9V and 12V.

As this is 35W source, I suppose that 20v is 1.75A and 15V is 2.33A.
Thus STUSB4500 PDOs need to be set accordingly.

Best regards

Nathalie

[AshutoshK]

Hello,

Yes, this is 35W source with 20v, 1.75A and 15V, 2.33A.

I have surpassed 9V and 12V profiles and in GUI I have set PDO's as given in image below.

I have tried 15V 0.5A, 15V,1A , 15V 1.5A, 15V 2A. But nothing worked. Tried entering current value lesser than source current for 15V and 20V it also doesn't worked.

[NBALL]

Please provide the NVM content you used.

Best regards

Nathalie

[AshutoshK]

Below is the NVM content I used. I have also tried with PDO 15V, 2A .

 

[NBALL]

Looks OK.
Did you take care to remove all supply of stusb4500, to guarantee NVM download after it has been written ?

Nathalie