| 主权项 |
1. A control circuit in a boost switching regulator, the boost switching regulator being configured to receive an input voltage on a first terminal of an inductor and to generate a regulated output voltage on an output terminal for driving a load, the boost switching regulator comprising a main power switch coupled between a second terminal of the inductor and ground, a synchronous rectifier coupled between the second terminal of the inductor and the output terminal, and an output capacitor coupled to the output terminal and ground, the control circuit being configured to control the main power switch and the synchronous rectifier using a Pulse Frequency Modulation (PFM) feedback control loop, the regulated output voltage being fed back to the boost switching regulator as a feedback voltage on a feedback node of the feedback control loop, the control circuit comprising:
a peak inductor current modulation circuit configured to receive a first current indicative of a load current flowing to the load and to generate a peak inductor current set value as a function of at least the first current, the input voltage, the regulated output voltage and a fixed current value; a comparator comparing the peak inductor current set value to a second current indicative of an inductor current flowing in the main power switch, the comparator generating a comparator output signal; and a PFM control circuit configured to receive the comparator output signal and to generate a first control signal for turning on the main power switch for a given duration, wherein the PFM control circuit adjusts the duration for turning on the main power switch in response to at least the comparator output signal. |
