A switching regulator includes a power stage, an output capacitor, a first
reference voltage generator, a first virtual ripple generator, a
comparator, and a constant-time trigger. The power stage includes a first
switch, a second switch coupled to the first switch, and an output
inductor coupled to the first switch and the second switch. The output
capacitor coupled to the output inductor with an output voltage across
the capacitor. The first virtual ripple generator is coupled to the first
reference voltage generator for generating a first modulated reference
voltage which reverses the output voltage according to the first
reference voltage. The comparator includes a first input end coupled to
the output inductor and the output capacitor and a second input end
coupled to the first virtual ripple generator. The constant-time trigger
is coupled between an output end of the comparator and a control end of
the power stage.