UCC28070-Q1 4-phase 90°-interleaved PFC system

Hi,
Your questions are
(1) How does the IC detect that the clock is synchronized 180 degs out of phase.
The answer is that it does not detect synchronization. The sync signals (SYNC1 and SYNC2) should be 180 degs out of phase but the UCC28070 does not check for this.
Regards,
John Griffin

Hello John,
Thank you for your reply.

Is the coil current like Q2?

Best regards,
Daisuke

Hi Daisuke,
Yes the currents would be the same shape as the Q2 waveform in your document.
Regards,
John

Hello John,
Thank you for your reply.

When the ON-DUTY is 50%, the phase-shifting is not 90° but 180°.
Please teach me the reason.
I attach a file.

PFC_4-phase_phase-shiting.pptx

The conditions are as follows.

(1)SS-pin Output impedance is 1/2. Line is common with two ICs.
Past:Css=3.2uF
Now: Css=6.4uF
(2)VAO-pin Output impedance is 1/2. Line is common with two ICs.
　 Past:Cpv=0.33uF, Czv=3.2uF, Rzv=43kohm
　 Now: Cpv=0.66uF, Czv=6.6uF, Rzv=22kohm
(3)Rimo-pin　Output impedance is 1/2. Line is common with two ICs.
　 Past:Rimo=43kohm
　 Now: Rimo=22kohm
(4)Vsense Line is common with two ICs.
(5)Vinac Line is common with two ICs.
(6)PKLMT Line is common with two ICs.
(7)CDR-pin snd Vref-pin is shorted. Ccdr is the same in the past.
(8)Rrt Calculated by equation-8.
(9)Rdmax Calculated by equation-4. Satisfying equation-10.

Past is 2-phase. Now is 4-phase.

Best regards,
Daisuke

Hi Daisuke

The waveforms you attached show the inductor currents.

You should look at the gate drive signals and you will find that the gate drives have the correct phase relationship.

Regards,

John

Hello John,
Thank you for your reply.

I ask customer to check the gate drive signals.

And,

Could you please check the circuit parameter described above(1~9)?
Please teach me problems if there are problems.

Best regards,
Daisuke