Patent ID: 6943504

Claim:
An apparatus for controlling an output current (I OUT ) that is delivered to a load circuit from an inductor, the apparatus comprising: a transistor switching circuit that is arranged to selectively couple a switch node to a power supply when activated, such that the inductor is charged by an input voltage (V IN ) when the transistor switching circuit is activated, wherein the inductor is arranged to deliver the output current (I OUT ) to the load circuit when the transistor switching circuit is deactivated; a ramp generator circuit that is arranged to provide a ramp signal (V RAMP ), wherein the ramp signal (V RAMP ) is reset to a predetermined level in response to a reset signal (ENR); a comparator circuit that is arranged to compare the ramp signal (V RAMP ) to a reference signal (V REF ) to provide a comparison signal (V COMP ), wherein the comparison signal (V COMP ) is asserted when the ramp signal (V RAMP ) exceeds the reference signal (V REF ); a feed-forward circuit that is arranged to activate a pulse signal (V FF ) when a voltage (V SW ) associated with the switch node decreases by a predetermined amount; and a latch circuit that is arranged to: assert the reset signal (ENR) when the pulse signal (V FF ) is asserted, activate the transistor switching circuit when the reset signal (ENR) and the comparison signal (V COMP ) are de-asserted, and deactivate the transistor switching circuit when the comparison signal (V COMP ) is asserted.