Nuvoton Technology Corporation

Wen-Yi Li

Yeh-Tai Hung

Te-Ming Tseng

Wei-Chan Hsu

Ta-Chin Chiu

Tu-Yiin Chang

Yeh-tai Hung

A low power mode control module for a crystal oscillator which performs the following steps: detecting whether an oscillation output signal of the crystal oscillator is output stably; when the oscillation output signal of the crystal oscillator is output stably, comparing at least one of an oscillation input signal and the oscillation output signal with an amplitude control signal to determine whether to adjust the amplitude control signal; when the amplitude control signal does not need to be adjusted, generating an upper bound reference voltage and a lower bound reference voltage associated with the amplitude control signal; and according to whether the oscillation output signal exceeds a reference voltage range of the upper reference voltage and the lower reference voltage, generating a low power mode control output signal associated with a crystal oscillator enable signal for enabling the crystal oscillator.

Low power mode control module and method for crystal oscillator, and circuit using the same

A control circuit driving a display panel and including a transmission interface, a charging circuit, an image driving circuit, and a loading management circuit is provided. The transmission interface is configured to be coupled to the display panel. The charging circuit is configured to charge a capacitor. The image driving circuit transforms the voltage of the capacitor into a plurality of driving signals and provides the driving signals to the display panel via the transmission interface. The loading management circuit measures the charge time of the capacitor. In response to the charge time of the capacitor exceeding a threshold value, the loading management circuit asserts a flag to indicate the occurrence of an overload.

Control circuit and display device

Provided is a system for testing a reference voltage circuit applicable to a reference voltage circuit. The reference voltage circuit includes a bandgap reference voltage circuit, switching elements, a first capacitor, a second capacitor and a comparator. The testing system includes a control logic unit. In a test mode, the control logic unit adjusts an allowable value of the comparator to speed up the suitability test of the switching elements.

System and method for testing reference voltage circuit

A microcontroller unit (MCU) is provided. The MCU includes a reset circuit, a clock circuit, a detection circuit, a counter and a control circuit. The detection circuit detects a first EFT event, and when a first EFT event is detected, the detection circuit generates a first block signal. The counter is coupled to the detection circuit, and when the counter receives the first block signal, the counter starts to count. The control circuit is coupled to the reset circuit, the clock circuit and the counter, and receives the first block signal from the counter. When the control circuit receives the first block signal, the control circuit maintains output signals of the reset circuit and the clock circuit in a prior state, in which the output signals have not been influenced by the first EFT event, until the count number of the counter reaches a default value.

Microcontroller unit and protection method for EFT events

A reference voltage circuit is provided, which includes bandgap reference circuit, bias current generator, first capacitor, second capacitor, comparator and control logic circuit. In the active mode of the control logic circuit, the control logic circuit controls the bandgap reference circuit to deliver bandgap reference voltage. The comparator transmits first comparison signal to control logic circuit when the first and second capacitors are charged to the bandgap reference voltage. The control logic circuit enters low power mode and controls the bandgap reference circuit to stop delivering the bandgap reference voltage. If the comparator detects the potential difference between the first capacitor and second capacitor exceeds the threshold value, the control logic circuit returns to active mode according to the second comparison signal transmitted form the comparator.

Reference voltage circuit

A voltage detection circuit including a comparator circuit, a tunable gain circuit and a switch circuit is disclosed. The comparator circuit has a first input terminal and a second input terminal. The tunable gain circuit is coupled between the first input terminal and a reference signal. The tunable gain circuit has a plurality of gain configurations. The tunable gain circuit adjusts the reference signal and transmits the adjusted reference signal to the first input terminal. The switch circuit selectively transmits a signal under test or the reference signal to the second input terminal. When the voltage detection circuit is in an auto-trimming mode, the switch circuit transmits the reference signal to the second input terminal and the tunable gain circuit sequentially adopts the gain configurations until the comparator circuit detects that voltage levels of the first input terminal and the second input terminal are substantially equal.

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Taipei, Taiwan

Wen-Yi Li