L6566B Flyback controller in constant frequency mode...how connect ZCD pn?

[treez]

Hello,
L6566B can operate in Quasi resonant mode or constant frequency mode. Do we need to ground the ZCD pin if we wish to use it in constant frequency mode? The datasheet doesn't appear to tell this..

L6566B datasheet
https://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/CD00167474.pdf

 

[Anna Conda]

For fixed freq, a cap from pin6 to GND is needed, and, pin 12 open circuit or to pin 7 for slope compensation.

" The signal on the ZCD pin in this case is used only for detecting
feedback loop failures (see Section 5.11: OVP block on page 35)."

All this is in the data sheet if you care to read it carefully....