Abstract: A touch pad and a position detecting circuit and method thereof are provided. The touch pad uses a waveform generator to generate an input signal; the input signal is capable of gradually moving a position of a zero voltage on the sensing pad in a predetermined direction. The touch pad also uses the zero voltage detector to detect when a zero voltage of the sensing signal of the sensing pen occurs so as to determine the position of the sensing pen on the sensing pad. Hence, the analog-to-digital converter is not required. Therefore, the resolution can be easily expanded, and the cost, the preciseness, and the specification can be easily controlled.

Abstract: A real-time object motion detection system includes a first object and a second object in relative movement, wherein: the first object sequentially sends a plurality of signal pairs at continuous time points, every signal pair comprising a first signal and a corresponding second signal, and a first propagation speed of the first signal is faster than a second propagation speed of the second signal; and the second object receives the plurality of first signals and second signals, wherein after receiving one first signal, the second object starts to count until receiving the corresponding second signal to obtain a time difference, and then utilizes the time difference to calculate a relative movement distance and speed.

Abstract: A Delta-Sigma modulator is disclosed, which has a Delta adder, a Sigma adder, a first latch, a second latch and a feedback generator, wherein the feedback generator provides a feedback signal to the Delta adder based on a pre-stage data signal provided by the first latch, so that the Delta adder provides a pre-stage addition signal. The Sigma adder performs an accumulation to provide an accumulative signal to the first latch, so that the first latch provides a pre-stage data signal to the second latch to enable the second latch to output a digital output signal.

Abstract: A Delta-Sigma modulator is disclosed, which has a Delta adder, a Sigma adder, a first latch, a second latch and a feedback generator, wherein the feedback generator provides a feedback signal to the Delta adder based on a pre-stage data signal provided by the first latch, so that the Delta adder provides a pre-stage addition signal. The Sigma adder performs an accumulation to provide an accumulative signal to the first latch, so that the first latch provides a pre-stage data signal to the second latch to enable the second latch to output a digital output signal.

Abstract: A radio frequency identification (RFID) communication system and the search method thereof are disclosed, which apply search instructions and reads instructions to communicate between a read and a plurality of transponders. Each transponder generates a random number for comparison with received search instructions. When the random number meets with the number of received search instructions, a response request is sent by a corresponding transponder such that the reader can read the content of the corresponding transponder.

Abstract: A panel sensing device and a positioning location searching method of the same are disclosed. A control unit serves to provide at least one reference voltage and at least one reference voltage with opposite phase. Thereby, a plurality of position blocks are defined by the electric field distributions produced by the reference voltages. A sensing pen is used to touch the sensing plate for sensing the object voltage of a touch position. The control unit searches the touch position according to the phase and level of the object voltage and the reference voltages.