Switched mode power supply having improved transient response

摘要

A switched mode power supply has a high side switching transistor coupled between a voltage source and a load for generating the output voltage at the load. A driver circuit drives the high side switching transistor. A first resistor divider is coupled to the output voltage and has a first tap. An error amplifier has a first input coupled to the first tap and a compensated feedback loop. A second resistor divider is coupled to the output voltage and has a second tap, resistance of the second resistor divider being less than resistance of the first resistor divider. A switch is coupled to the second tap and to the first input of the error amplifier for connecting the second tap to the first input of the error amplifier when the output voltage of the switched mode power supply reaches a first predetermined voltage.