Dithering for constant on time control loop

A pulse generator for generating pulses setting an on-time utilized for switching a DC-DC converter, the pulse generator comprising:

• a voltage divider coupled between an input voltage and ground, with a dithered reference voltage being produced at a tap of the voltage divider;
• a voltage to current converter arrangement generating a charging current having a magnitude that is based upon the dithered reference voltage;
• a timing capacitor configured to be charged by the charging current;
• a reset switch configured to selectively discharge the timing capacitor;
• and
• a comparator configured to generate a pulse based on a comparison between a timing voltage stored on the timing capacitor and a reference voltage, with a width of the pulse being set as a function of a rate of the charging of the timing capacitor by the charging current;
• wherein the voltage divider is configured to incrementally change a resistance seen at the tap of the voltage divider so that the dithered reference voltage is modulated in a stair-stepped triangular fashion.