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.

 

[NBALL]

Hello

I'm used to change PDOs on stusb4500 and I never faced issues.

Many customers modify also our default settings, to fit their application, without any issue.

To trace protocol, you need to insert protocol sniffer or to use oscilloscope able to decode USB¨PD traces.

Also please share full NVM map.

Best regards

Nathalie

[AshutoshK]

Okay thankyou, I'll share the details of NVM map shortly.

[AshutoshK]

Hello NBALL,

Sharing NVM data below for 15V PDO switching issue.

NVM data from Local:

0xC0: 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0xC8: 0x10 0x60 0x9C 0x1C 0xF0 0x01 0x24 0xDF
0xD0: 0x72 0x40 0x0F 0x00 0x32 0x00 0xA0 0xF5
0xD8: 0x00 0x19 0xB4 0x5F 0xF5 0x0F 0xF5 0x00
0xE0: 0x00 0x4B 0x32 0x21 0x43 0x00 0x50 0xFB

Regards,

Ashutosh K.

[AshutoshK]

Hello there,

There is an update on the issue we were discussing. I used different source of 65W and it resolved the issue of +15V PDO selection. I'm able to select any PDO profile.

I'm stuck in one issue, when the +15V is provided further to a device and when that device is switched ON-OFF-ON rapidly through SPST switch the VSYNK voltage is lost.

This issue is randomly arising and it is restored by restarting PD adapter from mains switch.

Kindly need help on this.

Best Regards,

Ashutosh Kedare.

[NBALL]

Hello

When using SPST system might have difficulties to see detach properly and so  to restart attachment + power nego properly.

As per TypeC spec, when detachment occurs, VBUS shall discharge down to below 0.8V on source side and within vSafe5v on sink side, in order to be able to restart.

CC pins have also a debounce time on sink side.

You should monitor CC pins + vbus during your SPST toggle to see how long it last + voltages.

Best regards

Nathalie

[AshutoshK]

Hello,

Thankyou but I'm not cutting of VBUS it is there continuously. I'm switching at the sink side on VSYNK line which is after MOSFET.

VBUS is not affected it is continuously present but VSYNK which is the voltage after mosfet is affected.

Regards,

Ashutosh K.

[NBALL]

please provide a block diagram + vbus/vsink snapshot on scope on SPST toggle

Regards

Nathalie

[AshutoshK]

Hello,

Here are the waveforms for VSYNK (Pink) and Switch (Blue). Captured onn the event of abnormal operation.

 

 

Regards,

Ashutosh K.

 

[NBALL]

It can be that switch closure generates undershoot on VBUS_VS_DISCH pin so that stusb4500 detaches.
If at same time CC pin goes to high level, it means it was overshoot (over voltage detected) otherwise, it is undershoot.
Having vbus_vs_disch pin voltage on scope might help

Best regards

Nathalie

[AshutoshK]

Hello NBALL,

Attaching Normal Operation and Abnormal Operation DSO shots.

***Normal Operation***

Yellow: Switch OFF and Switch ON condition

Blue: Vbus_Vs_Disch (constant +15V)

Pink: VSNK (+15V)

***Abnormal Operation***

Yellow: Switch ON condition (Not Made OFF)

Blue: Vbus_Vs_Disch (dropped for sometime)

Pink: VSNK (falled to 0) 

What necessary steps must I take to avoid falling of the Vbus_Vs_Disch?

Regards,

Ashutosh K.