Another thing the designer needs to be careful with when designing the system, is where the system may look stable but it’s not due to multiple crossings of zero dB. This will happen when a small inductor value and output capacitance is selected to reduce the size of the system. With lower switching frequencies the double pole frequency will occur after crossing over zero dB for the first time. The gain will then come up crossing zero dB again and come back down across for a third time. This is not a guaranteed stable system, although good results occasionally result in this operating mode. It is cautionary to check the operation of the system over all conditions for load transients.