Ramp offset compensation circuit in a buck boost converter

摘要

A converter includes a buck boost converter circuit to generate an output voltage in response to an input voltage, and an inductor current compensation circuit to generate an output current compensated inductor current signal corresponding to a sensed input current. The output current compensated inductor current signal includes a voltage gap between a boost ramp valley and a buck ramp peak. The buck boost converter circuit includes a current sensor to receive the input voltage, the current sensor to sense an input current corresponding to the input voltage, an upper buck transistor coupled to the input voltage node, an upper boost transistor coupled to an output voltage node to output the output voltage, and an inductor coupled between the upper buck transistor and the upper boost transistor. The inductor current compensation circuit adjusts the voltage gap based on an offset compensation voltage corresponding to a switching frequency.