PFC IC shutting down - ICE2PCS02GXUMA1

[arun1979]

Hello, I am using ICE2PCS02GXUMA1 in my PFC design where input power requirement is about 750-800W.

In my design, the PFC IC shuts down, once I cross about 525W at the input power. Once the load is reduced, the IC starts to operate again.

Schematic is attached.

Any help would be greatly appreciated.

Thank you, 

Arun

[cynic_bandera]

Inductors saturation, check it, please.

[arun1979]

Hello Cynic, what is the best way to check the inductor saturation? Can you please advise. Thank you,

[cynic_bandera · Accepted solution]

I checked your inductor documentation, It saturates at 4.5A, although at full power 120VAC (the US) input, you must have a current of about 9A. You check the current form on the shunt resistor by oscilloscope it will be like this in the article https://electronics.stackexchange.com/questions/83072/calculating-the-saturation-current-of-an-induc... .

[arun1979]

Thank you sir, I noticed that as well and I have some higher current inductors on order that I'll test out. Do you have any recommendation on inductors for this type of design? Thank you again.

[cynic_bandera]

You check the curve inductance vs. current. We say roughly (because it may fall smoothly and it's not obvious) saturation starts when inductance drops by 10%. For example your inductor. 

You must choose an inductor with saturation current higher than abs max possible current including ripple at the worst condition at the lowest possible voltage (85VAC ?). Since you operate in CCM mode high frequency losses in magnetic are not important you can choose a core based on powder material (most optimal).

[Guruprasad_A]

Hi @arun1979 ,

We appreciate your question being posted in the Infineon community.

The PFC IC ICE2PCS02GXUMA1 has a number of protection features. Since IC shuts down as the load rises, PCL may be triggering . Can you check the VSENSE pin voltage and the PCL pin voltage? Provide more details, such as input and output voltage and current.

Regards,

GA

[arun1979]

Thank you GA,

I am also thinking that either SOC or PCL is kicking in.  Is the PCL latching on non-latching?

The input to the system is 120VAC that is rectified using bridge rectified and then fed to the PFC circuit. The output is configured to be 375V DC (HVDC). I need to get about 700-800W of output power from this design.

I checked the vin input and that remains over 1.5V. 

Vsense voltage drops as the PFC shuts down and then Vsense is only generated by rectified AC voltage.

While monitoring the Isense pin, I can see that this pin is going below ~ negative 1.25V. I tried to disable the PCL circuit by reducing the sense resistor and even connecting the Isense pin directly to PGND. The issue remained as is with the Isense pin connected to GND and reducing the sense resistor.

Is there a way to disable the SOC and PCL function of the IC?

Thank you,

Arun

[Guruprasad_A]

Hi,

It appears like PCL is protecting your system.
evaluate the inductor. since the inductor is saturating. try to change the inductor value or part no. 

Regards,

GA