Abstract: The present invention provides a driving stage circuit, including a driving switch circuit and a conduction resistance adjusting circuit. The driving switch circuit generates an output signal according to a switch control signal. The conduction resistance adjusting circuit clamps the switch control signal to a first clamping level according to a current flowing through the driving switch circuit when the current is higher than a first current threshold, such that the conduction resistance of the driving switch circuit is not smaller than a first resistance so that a short circuit current of the driving switch circuit is not larger than a short circuit current limit, wherein a lowest level of the conduction resistance of the driving switch circuit is smaller than a second resistance and the output voltage level does not exceeds a output voltage limit when the current is lower than the first current threshold.

Abstract: A fingerprint sensor is disclosed. The fingerprint sensor includes a substrate, a sensing electrode, a shielding plate, a first pair of conductive plates and an amplifier. The sensing electrode is configured to detect a capacitance in response to a touch event on the fingerprint sensor, and configured to selectively receive or not receive an input voltage. The shielding plate is configured to selectively receive the input voltage or is coupled to a reference voltage level. The first pair of conductive plates includes a first plate selectively coupled to the sensing electrode. The amplifier includes an inverting terminal coupled to a second plate of the first pair of conductive plates, and a non-inverting terminal to receive a voltage that is a fraction of the input voltage. The sensitivity of the fingerprint sensor is directly proportional to the input voltage.

Abstract: The present invention provides a driving stage circuit, including a driving switch circuit and a conduction resistance adjusting circuit. The driving switch circuit generates an output signal according to a switch control signal. The conduction resistance adjusting circuit clamps the switch control signal to a first clamping level according to a current flowing through the driving switch circuit when the current is higher than a first current threshold, such that the conduction resistance of the driving switch circuit is not smaller than a first resistance so that a short circuit current of the driving switch circuit is not larger than a short circuit current limit, wherein a lowest level of the conduction resistance of the driving switch circuit is smaller than a second resistance and the output voltage level does not exceeds a output voltage limit when the current is lower than the first current threshold.