Dear e2e,
I would like to use TPS62441, its a great part. I need to synchronize its switching frequency to exactly 2MHz by applying a external clock to the SYNC pin.
I can see from the datasheet 7.5 and 7.6 these specifications and requirements:
- fsw tolerance with resistor from FSET to GND is -16% to +17%
- f(sync) (Synchronization clock frequency range applied to SYNC pin) must be at least fsw (set by the resistor +/- tolerance) up to fsw+20%
Therefore, I need to choose a FSET resistor such that the maximum fsw (i.e. at +17%) does not exceed 2MHz, because external clock must be >=fsw.
But the resistor-set fsw tolerance can be anywhere in range -16% to +17%. This range exceeds the 20% of SYNC frequency range requirement.
These tolerance requirements make synchronization to a clock unachievable without tuning the FSET resistor.
I must be misunderstanding something, please can you help?
