Dyna Image Corporation

Lite-on Semiconductor Corporation

Luxsentek Microelectronics Corp.

Wen-Sheng Lin

Sheng-Cheng Lee

Chun-Hsien Lin

Yu-Cheng Su

Peng-Han Chan

Chih-Wei Lin

Chen-Hua Hsi

Shih-Hao Lan

Yueh-Hung Ho

The present invention provides a light sensor with dark current elimination. A dark current from a covered photodiode and a sensed current from a photodiode are respectively transformed to a dark voltage and a sensed voltage by a controlled integration circuit. A reverse capacitor receives the dark voltage and the sensed voltage to cancel out for each other, and outputs a corrected sensing voltage.

Light sensor with dark current elimination having duo switch-capacitor circuits and a reverse capacitor

This invention provides an earphone with a low light transmittance and a non-porous sensor cover. Covering the sensing cover on the proximity sensing device can reduce the interference of most of the ambient light and improve measurement accuracy.

Earphone with proximity sensing function

Disclosures of the present invention describe an optical proximity sensor, which is particularly designed to have functionality of canceling an ambient light noise and/or an optical crosstalk noise by using light-to-frequency conversion technique, and comprises: a controlling and processing circuit, a lighting unit, a light receiving unit, an analog adder, a first DAC unit, a second DAC unit, and a light-to-digital conversion (LDC) unit. In the controlling of the controlling and processing circuit, the first DAC unit and the second DAC unit would respectively generate a first compensation current signal and a second compensation current signal to the analog adder, such that a noise signal of ambient light and a noise signal of optical crosstalk existing in an optical current signal of object reflection light would be canceled by the two compensation current signals in the analog adder.

Optical proximity sensor with self-compensation for ambient light and crosstalk using light-to-frequency conversion technique

The present invention provides a photosensor device with temperature compensation, which can adjust or calibrate the number, time and power of luminescence of light emitting elements under different ambient temperatures, so that the light signal values received by the photosensor device can be kept consistent or within the error range, there are multiple applications.

Photosensor device

A low power operation method provides an apparatus with a data transmission rate. A power management unit (PMU), which is not influenced by voltage, process, and temperature, biases a high frequency oscillator (HOSC) and makes the HOSC generate a steady and high precision clock. The clock of the HOSC is used to modify a timing length of a timer which is referenced by a low frequency oscillator (LOSC) without PMU. At last, through the modified timing length, the apparatus achieves high precision periods and data transmissions with compensation for voltage, process, and temperature. Thus, the data transmission cycles of the apparatus maintain stable and robust even if the apparatus applies duty cycle usage of the HOSC and the PMU for reducing power consumption with actions of turning on and turning off. Consequently, the periodic apparatus maintains data transmission rate with the low power consumption advantage of non-periodic apparatus.

Low power operation method for apparatus having data transmission rate

A digital device is provided. The digital device uses three states, including a ground (GND) state, a voltage (VDD) state, and a FLOAT state. On designing a chip, two storage units and a pad circuit are set inside; the pad circuit comprises a current limiter and two switches; and less ports contained are required than the conventional. That is, one port obtains three states. As comparing to the conventional having only two states, the present invention uses the port connected with two storage units in the pad circuit for obtaining the three states; a circuit featuring 'pull up' and 'pull down' is used to identify the state of connection of the port; and the port determines a plurality of definitions through the three states of GND, VDD and FLOAT. Thus, a pad is saved for reducing the space and cost of the chip.

Digital device using three states

A smart method is provided for a low-current oscillatory circuitry. The circuitry comprises an oscillator and a microcontroller unit (MCU). The oscillator comprises a proportional-to-absolute-temperature circuit connecting to a low-voltage regulator. The low-voltage regulator connects to a PMOS diode array and a delay unit circuit. The PMOS diode array connects to the MCU. The delay unit circuit connects to the MCU and a voltage converter. The method includes a normal temperature compensation algorithm; a smart learning algorithm of extra-high temperature compensation; and an ultra-high temperature compensation algorithm. Thus, clock variations are compensated; output frequency is stable and not affected by voltage or temperature variations; and process variations are suppressed. When process variations appear, there are not be too many errors generated. Therefore, a timebase clock is provided with high accuracy, wide operating voltage range, wide operating temperature range, and low power consumption operation.

Method for low-current oscillatory circuit with wide operation voltage and temperature compensation

A light sensor device is provided. It is controlled with a dual-mode master-and-slave microcontroller unit (MCU) application. An MCU is embedded into a light sensor chip. The original dual-mode master-and-slave dual-CPU architectures are combined to be operated as a single-CPU architecture. Since the original circuit pin design is followed, it is possible to be compatible with the old circuit design. The present invention uses a single-CPU architecture to directly control light sensors. Through the configuration of RAM, an inter-integrated circuit bus (IC I/F) can be redirected to an internal non-volatile memory to switch the operational mode of the light sensor chip from a slave machine to a host machine which switches off the interrupt pin and, then, turns to a GPIO pin. Thus, the present invention provides a simple single-CPU architecture with easy use and effectively-lowered cost.

Light sensor device controlled with dual-mode master-and-slave MCU application

Disclosures of the present invention particularly describe oscillator circuit with temperature compensation function, consisting of a fully differential amplifier, a current mirror unit, a bias current supplying unit, a compensation unit, and a reference signal generating unit. A variety of experimental data have proved that, based on the normal operation of the compensation unit and the reference signal generating unit, an oscillation frequency of this oscillator circuit would be maintained at same level even if the ambient temperature continuously increases. Therefore, because the frequency drift due to temperature variation would not occur in the oscillator circuit of the present invention, the novel oscillator circuit is potential oscillator to replace the conventional oscillators applied in analog-to-digital convertors or time-to-digital convertors.

Oscillator circuit with temperature compensation function

The present invention mainly discloses an optoelectronic receiver circuit with dark current correction function, comprising: a transimpedance amplifier (TIA), a first variable resistor, a second variable resistor, a photodiode, a leakage compensation photodiode, at least one first leakage correction photodiode, at least one first switch, at least one second leakage correction photodiode, and at least one second switch. In the present invention, the first switch and the second switch are used for enabling the first leakage correction photodiode and the second leakage correction photodiode when the dark current of the leakage compensation photodiode cannot fully cancel a leakage portion of a photodiode current of the photodiode, such that the leakage portion of the photodiode current can be completely eliminated by the dark current of the leakage compensation photodiode and the dark currents provided by the two leakage correction photodiodes.

Optoelectronic receiver circuit with dark current correction function and dark current correction method thereof

Differing from conventional optical sensing device used in smart phones often lacks self-calibration function, a novel proximity sensing device having self-calibration function is disclosed by the present invention, and comprises: a driving module, a lighting element, a first a light receiving module, a conversion module, a judge circuit, a synchronous sequential module, an analog front-end module, and an analog-to-digital convertor. When executing a noise calibration process, a sensing signal outputted from the first light receiving module is converted to a voltage signal by the conversion signal comprising a signal-amplifying MOSFET, a current mirror circuit, N number of cascode MOSFET pairs, and a current-to-voltage converting resistor. After that, the voltage is transmitted to the judge circuit, and then the noise calibration process would be completed under the cooperation of the judge circuit, the synchronous sequential module, and the analog front-end module.

Proximity sensing device and optical sensing circuit having proximity sensing function

Differing from conventional ambient light sensors at least having drawbacks of huge circuit area and high manufacturing cost, the present invention discloses an ambient light sensor showing advantages of small circuit area and low manufacturing cost. This ambient light sensor has functionality of photodiode leakage current compensation, and comprises: a temperature sensing unit, a microprocessor unit, a conversion unit, and a lookup table unit. The microprocessor unit is configured to find out a reference parameter for a first dark current from the lookup table unit according to a measured data of ambient temperature. Subsequently, the conversion unit is controlled to apply a current amplifying process to a second dark current. Therefore, after subtracting an output current of the first photodiode from the second dark current been treated with the current amplifying process, the output current been treated with a leakage current compensating process is produced and outputted.

Ambient light sensor with photodiode leakage current compensation

Differing from conventional LDO voltage regulator being unable to work at a sleep mode for saving power dissipation, the present invention discloses a smart low dropout (LDO) voltage regulator capable of being switched to an operation mode or a sleep mode based on the controlling of an enablable signal. This smart LDO voltage regulator comprises an input voltage detecting unit, a switch controlling unit and a voltage regulating module. During the sleep mode of the smart LDO voltage regulator, the switch controlling unit generates a switch controlling signal to change a switch setting of a switch unit of the voltage regulating module, so as to facilitate the smart LDO voltage regulator produce an output voltage through a first voltage regulating unit or a second voltage regulating unit of the voltage regulating module, or directly output input voltage as the output voltage.

Growing community of inventors

Taipei, Taiwan

Wen-Sheng Lin