METHODS AND APPARATUS FOR CONTROLLING IN-RUSH CURRENT DURING DYNAMIC CONTEXT SWITCHING

An image sensor may contain an array of imaging pixels arranged in rows and columns. To support lower speed operation while minimizing power consumption, the image sensor may alternate between a high power context and a low power context. When transitioning between the high power and low power contexts, an in-rush current limiting circuit may be used to slowly ramp up or ramp down the bias current to help minimize power supply voltage rippling. The in-rush current limiting circuit may be digitally controlled using a current ramping digital-to-analog converter, may implement linear current ramping, or may implement a current feedback ramping scheme.