Hi,
Perhaps someone could clarify.
Using the design tool of the ADP1612 I just specifify these targets (in order to get lowest possible ripple, I understand these limiting).
So i have these specs
And I get this
I'm a bit disappointed by the LC filter. I understand the crossover frequency and the filter resonance must be far apart enough to not cause stability issues and not to reduce the bandwidth of the control loop.
Yet, I recall using a boost IC (MIC2288, 1.2MHz) successfully with a damped RLC filter (same specifications regarding Vin Vout) that had a R(series)=0.9Ohm, L=33uH, C=22uF (along with the capacitor Cout1=1uF and the main boost inductor@10uH). This basically gave a approx. 4kHz cutoff for the filter and attenuated the ripple quite a bit, with decent stability.
I wonder why the same cannot be achieved with the ADP1612. Is this specific to the regulator? Would you recommend another one? I'm need to filter the ripple due tight noise constraints. I was looking for a better replacement basically.
Because as I check the specs the design tool gives me (I'm simply exploring at this point), I can't even use 1.3MHz because the time the switch is on isnt enough with 1.3MHz.
Thanks
