A buck switching regulator formed on an integrated circuit and receives an
input voltage and provides a switching output voltage on a switch output
node using a fixed on-time, minimum off-time feedback control scheme. The
buck switching regulator includes a first capacitor and a first resistor
formed on the integrated circuit where the first capacitor and the first
resistor are connected in series between the switch output node and a
feedback voltage node, and a second capacitor coupled between the DC
output voltage node and the feedback voltage node. The first capacitor
and the first resistor generate a ripple voltage signal being related to
the switching output voltage and provide the ripple voltage signal to the
feedback voltage node for use in the fixed on-time, minimum off-time
feedback control scheme where the magnitude of the ripple voltage signal
is a function of the capacitance value of the second capacitor.