Abstract: The present invention provides a photodetector, which comprises a substrate, a gate metal layer, an isolation layer, a transport layer, an insulating layer, an optoelectronic device, and a common metal layer. The gate metal layer is disposed on the substrate; the isolation layer is disposed on the gate metal layer and the substrate; the transport layer is disposed on the isolation layer; the insulating layer is disposed on the transport layer; the optoelectronic device is disposed on the transport layer but not on the gate metal layer; and the common metal layer is disposed on the optoelectronic device. In an etch-back process for removing the common metal layer, the transport layer cannot be removed. Alternatively, in another etch-back process for removing the transport layer, the isolation layer, and the layers and device on the isolation layer, the gate metal layer cannot be removed.

Abstract: An AC power supply and a method for dynamically controlling the output current thereof are disclosed. An output voltage stop signal is used to disable a DC/AC converter from outputting. During a period that the DC/AC converter stops its output, the output current of the DC/AC converter is measured and is fed back to a output current control device as an output current feedback signal to produce a deviation. Using the difference between the output current feedback signal of the DC/AC converter and the deviation, an approximate DC value of the output current of the DC/AC converter is calculated. With reference to the approximate DC value, the DC/AC converter can be controlled so that the DC current injection in the output current is approximately zero.

Abstract: An AC power supply and a method for dynamically controlling the output current thereof are disclosed. An output voltage stop signal is used to disable a DC/AC converter from outputting. During a period that the DC/AC converter stops its output, the output current of the DC/AC converter is measured and is fed back to a output current control device as an output current feedback signal to produce a deviation. Using the difference between the output current feedback signal of the DC/AC converter and the deviation, an approximate DC value of the output current of the DC/AC converter is calculated. With reference to the approximate DC value, the DC/AC converter can be controlled so that the DC current injection in the output current is approximately zero.