Abstract: An amplifying circuit, which can operate in one of a sample mode and a hold mode, comprising: an amplifier; a current providing circuit, configured to provide a first bias current to the amplifier in a power saving time interval when the amplifying circuit operates in the sample mode, and configured to provide a second bias current to the amplifier when the amplifying circuit operates in the hold mode; wherein the first bias current is smaller than the second bias current.

Abstract: A navigation device includes an image sensor, a processing unit, a main clock circuit and an auxiliary clock circuit, wherein a clock frequency of the auxiliary clock circuit is much lower than that of the main clock circuit. The image sensor captures a predetermined number of image frames in a burst period. The processing unit is configured to calculate a displacement according to the image frames, to disable the main clock circuit after the predetermined number of image frames have been captured by the image sensor and to restart the main clock circuit with the auxiliary clock circuit before the end of the burst period.

Abstract: The present disclosure provides a driving circuit, which includes a switch, a driver unit, a fault detection circuit, and a processor. The switch is coupled between a power terminal and an anode of a light emitting diode (LED) of a light source. The driver unit is coupled between a cathode of the LED and a ground for generating a driving current according to a control signal. The fault detection circuit operatively detects whether the cathode of the LED is shorted and generate a fault signal when detected that the cathode of the LED is shorted. The processor initiates a fault detection period, during which the processor turns off the switch and the driver unit causes the cathode of the LED to be floating while activates the fault detection circuit to detect whether the cathode of the LED is shorted.

Abstract: The present disclosure provides a driving circuit, which includes a switch, a driver unit, a fault detection circuit, and a processor. The switch is coupled between a power terminal and an anode of a light emitting diode (LED) of a light source. The driver unit is coupled between a cathode of the LED and a ground for generating a driving current according to a control signal. The fault detection circuit operatively detects whether the cathode of the LED is shorted and generate a fault signal when detected that the cathode of the LED is shorted. The processor initiates a fault detection period, during which the processor turns off the switch and the driver unit causes the cathode of the LED to be floating while activates the fault detection circuit to detect whether the cathode of the LED is shorted.

Abstract: An optical navigation sensor includes: a driving circuit and a charge pump. The driving circuit is employed for driving a light source externally connected to the optical navigation sensor. The charge pump is employed for intermittently performing an operation of providing a first supply voltage to the light source. When the driving circuit drives the light source, the charge pump does not perform the operation of providing the first supply voltage to the light source.

Abstract: An optical navigation sensor includes: a driving circuit and a charge pump. The driving circuit is employed for driving a light source externally connected to the optical navigation sensor. The charge pump is employed for intermittently performing an operation of providing a first supply voltage to the light source. When the driving circuit drives the light source, the charge pump does not perform the operation of providing the first supply voltage to the light source.

Abstract: A navigation device includes an image sensor, a processing unit, a main clock circuit and an auxiliary clock circuit, wherein a clock frequency of the auxiliary clock circuit is much lower than that of the main clock circuit. The image sensor captures a predetermined number of image frames in a burst period. The processing unit is configured to calculate a displacement according to the image frames, to disable the main clock circuit after the predetermined number of image frames have been captured by the image sensor and to restart the main clock circuit with the auxiliary clock circuit before the end of the burst period.

Abstract: A driver circuit for a Light Emitting Diode (LED) is disclosed. The driver circuit is capable of supporting a constant LED current circuit configuration as well as an external resistor-controlled LED current circuit configuration. By integrating both configurations into a single driver circuit, the either circuit configuration can be selected without requiring a different driver circuit.

Abstract: A driver circuit for a Light Emitting Diode (LED) is disclosed. The driver circuit is capable of supporting a constant LED current circuit configuration as well as an external resistor-controlled LED current circuit configuration. By integrating both configurations into a single driver circuit, the either circuit configuration can be selected without requiring a different driver circuit.

Abstract: An input device with a power saving system is provided for reducing the power consumption of the input device when the input device is at rest. The input device may include a sensor, a rest mode switch, control logic and a current controller. The sensor may be configured to obtain an image data in response to a light incident on the sensor. The rest mode switch may be configured to set the input device to various levels of rest modes when it is inactive. The control logic may be coupled to the rest mode switch and the sensor. The control logic may be configured to set the input device to process a portion of the image data on the sensor array during a wake up detection operation when the input device is at rest. The current controller may be coupled to the control logic and the sensor and configured to control the current supply limited to a section of the sensor array containing the portion of image data that is being processed by the input device during the wake up detection operation.

Abstract: An optical navigation sensor receives light that is produced by a light source and reflected from a surface. The optical navigation sensor has a silicon substrate having a plurality of photo-sensing regions, each of which receives a portion of the reflected light, and each of which provides a pixel of navigation information. At least one layer of material is deposited on the photo-sensing regions of the silicon substrate during a silicon wafer fabrication process. Each layer has a thickness that causes it to serve as an anti-reflection coating and reduce a percentage of light that is reflected away from the photo-sensing regions of the silicon substrate. A circuit biases each of the photo-sensing regions with a current, the current providing a given responsivity, and the current being less than a current that would be required to provide the given responsivity absent the at least one layer of material.