Temperature calibrated over-current protection circuit for linear voltage regulators

摘要

An apparatus and method provide for temperature calibrating an over-current limit in a linear regulator. Output current is delivered to the load through a power pass device that is responsive to a gate control signal. A transistor circuit provides a sense current that is proportional to the output current. A diode device senses the operating temperature of the linear regulator. An analog-to-digital converter converts the sensed operating temperature to a digital quantity. A resistance value associated with a resistance circuit is changed in response to the digital quantity. The resistance circuit converts the sense current to a voltage that is compared to a reference voltage. An amplifier is arranged to adjust the gate control signal when the reference voltage is exceeded such that the over-current condition is detected.