Figure 42.
PFC tuning: delta pin calibration
11.4.5
Step 3:TSW test
After computing the delta pin, the third step is to determine the mode changes based on the PFC frequency.
You have to manually select the minimum/maximum bounds for the PFC frequency.
During normal operations, if the PFC actual frequency crosses this boundary, a mode change is required.
To check the
Tsw range
, in the GUI:
•
PFC mode change is enabled on the basis of the PFC frequency (mode change based on the estimated
power is disabled)
•
The output power is swept across the operating range
•
Switching frequency is monitored and the user has to check that the mode change is stable (i.e. the IC does
not jump continuously from one mode to another because it crosses always a frequency limit during mode
change), adjusting the limits if the case.
Note:
If manual mode is selected, the GUI asks to smoothly ramp-up and down the DC load.
UM2342
Step by step calibration example
UM2342
-
Rev 1
page 36/57
