Nuvoton Technology Corporation

Chung Ming Hsieh

Yeh-Tai Hung

Ching-Yen Chiu

Po-Hsuan Huang

Chung-He Li

Wei-Chan Hsu

A signal conversion device for converting a single-ended input voltage into a differential input voltage having a positive input voltage and a negative input voltage is provided. During a sampling phase, a holding phase, and a common-mode voltage generation phase, a capacitor related to the positive input voltage is electrically connected to the single-ended input voltage, and a capacitor related to the negative input voltage is electrically connected to a preset voltage. During a single-ended to differential phase, the capacitor related to the positive input voltage is electrically connected to the preset voltage, and the capacitor related to the negative input voltage is electrically connected to the single-ended input voltage. Hence, the common-mode voltage is not related to a capacitance ratio, and the capacitors does not need to be designed as switching capacitors with multiple switches. No complex control is required, and the parasitic effect of the circuit can be reduced.

Signal conversion device and circuit system using the same

A power supply device is used to provide power to an encryption and decryption device of a security system, including a safety power supply device, which is used to supply the supply voltage according to the system voltage; a regulated voltage source, which is used to provide a regulated voltage; and a voltage selection device, which is electrically connected with the safety power supply device, the stable voltage source and the encryption and decryption device. During the startup period of the security system, or, after the startup period of the security system and the encryption/decryption device performs encryption/decryption, only the supply voltage is selected as the driving voltage of the encryption/decryption device. After the startup period of the security system and the encryption and decryption device does not perform encryption and decryption, the voltage only the regulated voltage is selected as the driving voltage of the encryption and decryption device.

Power supplying device, method and secure system

An embodiment of the present disclosure provides a conversion circuit for converting a single-ended input to a differential input, which has fewer switches and fewer capacitors. This conversion circuit increases the signal-to-noise ratio (SNR), and the conversion circuit directly uses the higher supply voltage AVDD without being bucked by the regulator, wherein the common mode voltage is AVDD/2N, and N is greater than 1. Overall, not only the circuit area is smaller and the SNR is higher, but also the manufacturing cost is reduced. In addition, compared with the prior art, the conversion circuit of the embodiment of the present disclosure has only three operation periods, so the control is simpler and the operation speed is faster.

Conversion circuit for converting single input to differential input and system circuit using the same

A power supply device for providing a driving voltage of an encryption/decryption device. When the encryption/decryption device is in operation and its driving voltage falls within the voltage range formed by an upper limit voltage and a lower limit voltage, only a supply voltage provided by a secure power supply device is used as the driving voltage for the encryption/decryption device. When the encryption and decryption device is in operation and its driving voltage falls outside the voltage range formed by the upper limit voltage and the lower limit voltage, the supply voltage and a stable voltage provided by the stable voltage source are used as the driving voltage at the same time, the supply voltage is further adjusted until the driving voltage falls within the voltage range formed by the upper limit voltage and the lower limit voltage, and then continue to use only the supply voltage as the driving voltage.

An incremental analog-to-digital converter including a first-stage non-delay memorization element and other elements is disclosed. An ending time point of a second reset signal received by the first-stage non-delay memorization element is later than an ending time point of a first reset signal received by the other elements by at least one clock cycle, a reset duration of the first-stage non-delay memorization element is longer than a reset duration of the other element, so that the first-stage non-delay memorization element can be prevented from occurring overshoot or spike on an output thereof, and the incremental analog-to-digital converter can maintain a good signal-to-noise and distortion ratio under the condition that the internal elements has low swing limits.

Incremental analog-to-digital converter and circuit system using the same

A protection circuit is adapted to a switching-capacitor regulation circuit having a capacitor. The protection circuit comprises a current source, first and second switch circuits, and a control unit. First, the control unit turns on the second switch circuit to make a top end and a bottom end of the capacitor, and control the first switch circuit to make the current source no connect the capacitor, and then set a voltage of the top and the bottom to be a first preset voltage. Next, the control unit turns off the second switch circuit to disconnect the top end and the bottom end, and turn on the first switch circuit to flow current from the bottom end of the capacitor. When a voltage difference between the top end and the bottom end is equal to a preset initial voltage, the control unit control the first switch circuit to disconnect the current source and the capacitor; next, the control unit controls current flow in or out from the top of the capacitor based on the voltage on the top of the capacitor.

Protection circuit and operation method thereof

A zero current detection system for a switching regulator is provided. The switching includes an inductor. In the zero current detection system, a comparator has a positive input coupled to a terminal of the inductor and an output terminal for outputting a comparison result signal; a first signal latch circuit has a clock terminal for receiving the comparison result signal and outputting a latched output signal; a delay line module starts counting upon receipt of the latched output signal, and then outputs a zero current detection signal after counting a delay time; in response to the zero current detection signal, a voltage sampling module samples a node voltage at two different time points, to generate two sampling voltages; a delay control module adjusts the delay time of the delay line module according to the two sampling voltages.

Zero current detection system used in switching regulator comprising an inductor

A dynamic comparator includes a differential amplifier stage, a switching unit and a switching charge storage unit. The switching charge storage unit includes a plurality of switching transistors, and a charge storage capacitor electrically connected to the plurality of switching transistors. When an operational mode of the dynamic comparator is switched from a comparison state to a reset state, a voltage on one of a first terminal and a second terminal of the charge storage capacitor is increased from a half of the system voltage to a system voltage, so as to implement a charge recycle effect. The dynamic comparator of the present invention can have lower power consumption and lower charge-discharge current.

Dynamic comparator and circuit system using the same

A digital regulator system is provided. The digital regulator system includes a digital regulator circuit and a compensation circuit. The digital regulator circuit outputs an output current and an output voltage. The digital regulator circuit adjust the output current by decreasing or increasing a unit current according to at least a reference voltage and a feedback voltage. The compensation circuit receives the output voltage as well as decreases or increases a unit voltage of the output voltage to generate and output the feedback voltage according to the variation of the output current.

Digital regulator system and control method thereof

A startup circuit initializes a voltage of a capacitor of a switch-capacitor regulator. The startup circuit includes a voltage forming circuit and a control unit. The voltage forming circuit selectively electrically connected to the top and the bottom of the capacitor. In a first operation phase, the voltage forming circuit is electrically connected to the top and bottom of the capacitor, and the top and bottom of the capacitor are connected to each other, and the voltages of the top and bottom are set as a preset high voltage. In a second operation phase, the voltage forming circuit disconnects the top and the bottom, and generates current flowing out from the bottom of the capacitor until the voltage cross the capacitor is equal to the preset initial voltage. In the third operation phase, the startup circuit is disconnected from the capacitor.

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Hsinchu Science Park, Taiwan

Chung Ming Hsieh