Some electronic circuits, such as power supplies or power metal-oxide-semiconductor field-effect transistor (MOSFET) circuits include a current sensor circuit. The current sensor circuit may be used, for example, to sense a current flowing through a load and to trigger an overcurrent protection circuit when the load current is above a predetermined threshold. For example, an electronic fuse (e-fuse) is an active circuit that may rely on a current sensor circuit to provide over-current protection.
Some circuits may use a current sensor circuit to regulate a current. For example, in a light-emitting diode (LED) driver, a current sensor circuit may be used to monitor a current going through a LED and produced a feedback signal based on the sensed current. A controller may use the feedback signal produced by the current sensor circuit to regulate the current flowing through the load to achieve, for example, a constant current.
Some circuits may have operating conditions with a wide range of power supply voltages. For example, although the typical operating voltage in a car battery is 12 V, variations between 9V and 16 V are expected during normal operation. During a cold cranking condition, the voltage of the battery of a car may drop to a voltage lower than 5 V. It is common, therefore, for devices designed for the automotive industry to support operating voltages lower than 5 V as well as higher than 18 V. A current sensor circuit with operating conditions with a wide voltage range is expected to accurately sense the current through the wide voltage range.