Lite-on Semiconductor Corporation

Dyna Image Corporation

Peng-Han Chan

Chun-Hsien Lin

Sheng-Cheng Lee

Wen-Sheng Lin

Yu-Cheng Su

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

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.

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Taipei, Taiwan

Peng-Han Chan