Tool/software:
Hi team,
There are some application issues that need you help. I'll send the schematic and layout offline.
Vin(Vsys) is from battery charger, the range is 8.4V~ 12.45V.
Vout is 9.36V
There is no system load for TPS552882.
This issue can be found when battery is charging. The Vsys is from 8.4V increasing to 9.6V even 9.9V. During 9.6V~9.9V, they can find this issue.
Customer can find abnormal operating like audible noise when issue occur. And the noise will disappear when we use brand new IC. It seems that IC is damaged.
But if this process doing again, it could be found.
Besides, they can find abnormal switching frequency. We set FPWM 400kHz in SCH but we can find from 200kHz~700kHz.
https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/293.1349KHz.jfif
https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/567.2533KHz.jfif
https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/742.746KHz.jfif
We have room-in for off time.
Please let us know what can we try.
And we also capture a waveform. You can see when VSYS starts to drop. TPS552882 enters boost mode, but it's Vout up to 23V. Should it keep 9.36V?
Thanks,
Leo
