A synthetic ripple regulator including a synthetic ripple voltage
generator that generates a synthetic ripple voltage indicative of the
ripple current through an output inductor. The regulator uses the
synthetically generated ripple voltage to control toggling of a
hysteretic comparator for developing the pulse width modulation (PWM)
signal that controls switching of the regulator. In a non-limiting
implementation, a transconductance amplifier monitors the phase node
voltage of the inductor and supplies an inductor voltage-representative
current to a ripple capacitor, which produces the synthetic ripple
voltage. Using the replicated inductor current for ripple regulation
results in low output ripple, input voltage feed forward, and simplified
compensation.