Holtek Semiconductor Corp.

Chi-Ho Hsu

Min-Kun Wang

Fang-Diahn Guo

Wen-Ping Cheng

Chi-Bing Chen

Chun-Lin Shen

Hsan-Fong Lin

Minkun Wang

Chia-Lu Hsu

A power processing interface for a radio frequency identification system is provided. The power processing interface includes a resonance circuit for inducing a first signal transmitted from a terminal as an AC voltage, a first rectifier circuit electrically connected to the resonance circuit for converting the AC voltage into a DC voltage, a filter circuit electrically connected to the first rectifier circuit for generating an operating voltage in response to the DC voltage, a voltage-detecting circuit electrically connected to the filter circuit and the first rectifier circuit for detecting the magnitude of the operating voltage, a second rectifier circuit electrically connected to the resonance circuit, and a voltage-clamping modulation circuit electrically connected to the first rectifier circuit, the voltage-detecting circuit and the second rectifier circuit for controlling the conduction of the second rectifier circuit in response to the output of the voltage-detecting circuit so as to bypass the excessive current, and for providing a minimum voltage to the radio frequency identification system during the modulation process so as to keep the radio frequency identification system in a normal operation.

Power processing interface for passive radio frequency identification system

A method for calibrating a parameter of an IC, using an external device so as to calibrate an analog control parameter of an internal analog circuit in the IC. The external device is used in a detecting mode so as to detect whether the analog control parameter is beyond a pre-determined range. If the analog control parameter is beyond the pre-determined range, the external device is used in a calibrating mode so as to obtain a calibrated value and the calibrated value is then written into the internal analog circuit in the IC. The external device is used for detection and calibration repeatedly until the analog control parameter is within the pre-determined range. When the analog control parameter is within the pre-determined range, the calibrated value is written into a non-volatile memory in the IC.

Method for calibrating parameter of integrated circuit

A circuit capable of providing stable timing clock includes: a step-down clamping circuit, an oscillating circuit, and a voltage potential-conversing circuit. The step-down clamping circuit that step down the input first voltage potential, and clamp to output second voltage, the oscillating circuit is coupled to the clamping circuit and is an oscillating circuit that takes the second voltage as a operating voltage to generate a first timing clock signal, which has a lower voltage potential. The voltage potential-conversing circuit is coupled to the oscillating circuit to convert the first timing clock signal into a second timing clock signal, which has a higher voltage potential. And it is a stable timing clock signal available for other system circuit.

Stable timing clock circuit

An environment monitoring integrated circuit is provided that allows the boundaries of operating parameters to be conveniently modified. The present invention allows the hardware designer to easily change the temperature boundary of the computer operation, or the boundaries of the operating voltage, the operating temperature and the rotation speed of the fan. The present invention uses limit registers which provide a simple implementation for changing the boundaries of the operating parameters of the computer.

Computer environment monitor device

A photocoupling signal detection circuit for a computer mouse to simplify the design of circuit by tracking the slope change of input voltage waveform and produce a digital output which can detect the movement of computer mouse is disclosed. This signal detection circuit includes a comparator, a state decision circuit, an up/down counter, and a D/A converter. The comparator produces an up/down signal connected to the state decision circuit, then the up/down signal connected to the up/down counter to transfer the up/down signal into a digital signal output. The digital signal connected to a D/A converter for transferring into an analog signal, and the analog signal can be compared with the output signal of an phototransistor. According to the state of up/down signal, the state decision circuit determines if the phototransistor is turned on or turned off and outputs different state signals, based on its determination. The output state signal is further utilized for the detection of a computer mouse.

Growing community of inventors

Hsinchu, Taiwan

Chi-Ho Hsu