This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

UC1843A: oscillator frequency setting

Part Number: UC1843A
Other Parts Discussed in Thread: UC3842

Tool/software:

From UCx84x datasheet (SLUS223G – APRIL 1997 – REVISED JULY 2022)  Section 8.3.7 states: “The UC3842/3/4/5 oscillator must be set to a lower frequency than the sync pulse stream, typically 20%..”

 

Does setting the sync frequency 20% below the oscillator account for the oscillator initial accuracy and temperature stability  called out in the OSCILLATOR SECTION of the 7.5  Electrical Characteristics Table?

 

I’m trying to determine how critical the “typical 20%” lower oscillator frequency is.  For example if my sync frequency is 300KHz, is setting the oscillator at 240KHz sufficient?

Or

Should I account for the oscillator initial accuracy and temperature stability to verify the calculated maximum oscillator frequency is 20% less than the sync frequency?