Realtek Semiconductor Inc.

Leaf Chen

Ya-Hsuan Sung

Bo-Yu Chen

Guan-Yu Chen

Li-Cheng Chu

Chien-Wen Chen

Jiun-Hung Pan

An-Ming Lee

Ming-Hui Tung

Tsung-Yen Liu

Kai-Yuan Yin

Li-Chen Liu

Wen-Bin Wu

Jiun-hung Pan

Jiun Hung Pan

A bidirectional signal conversion circuit is configured to perform a signal conversion between a first port and a second port, and includes a switch, a first pull-up resistor, a second pull-up resistor, a first output-response enhancement circuit, and a second output-response enhancement circuit. The switch is coupled between the first port and the second port, and operates according to a bias. The first (second) pull-up resistor is coupled between the first (second) port and a high (low) voltage terminal having a high (low) voltage. The first (second) output-response enhancement circuit includes a first (second) alternative-current (AC) coupling circuit and a first (second) output-stage circuit. When the first (second) port and the second (first) port functions as an input port and an output port respectively, the first (second) output-response enhancement circuit is operable to accelerate the transient response of the output port.

Bidirectional signal conversion circuit

A power supplying circuit includes a first high-voltage switch, a first low-voltage switch, a second high-voltage switch, a second low-voltage switch, and a controller circuit. The first high-voltage switch receives a first input voltage and generates a first node voltage. The first low-voltage switch is coupled between the first high-voltage switch and an output terminal. The second high-voltage switch receives a second input voltage and generates a second node voltage. The second low-voltage switch is coupled between the second high-voltage switch and the output terminal. The controller circuit controls the first high-voltage switch, the first low-voltage switch, the second high-voltage switch, and the second low-voltage switch according to the first node voltage and the second node voltage such that an output voltage is outputted to the output terminal.

Power supplying circuit and power supplying method

An electronic device having a universal serial bus (USB) power delivery function includes a connector, an electrostatic discharge (ESD) protection circuit, a power reception notification circuit, and a control circuit. The connector is coupled to a USB host. The connector includes a configuration channel (CC) pin. The power reception notification circuit is configured to turn on, in response to an enable signal, a pull-down path of a pull-down circuit of the ESD protection circuit. The configuration channel pin generates a pull-down voltage through the pull-down path of the pull-down circuit when the pull-down path is turned on. The control circuit is configured to send the enable signal to the power reception notification circuit when a trigger signal that meets a power reception condition is detected. The control circuit controls the connector to draw power from the USB host when the pull-down voltage of the connector is greater than a pull-down threshold.

Electronic device having USB power delivery function

The present invention discloses a USB signal output circuit having reverse current prevention mechanism. A switch circuit turns on when a switch control terminal receives a first high level voltage to output a signal from a signal input terminal to a signal output terminal. A first voltage pull-low circuit includes a passive-component high-pass filter circuit and a discharging circuit. The passive-component high-pass filter circuit couples an output terminal voltage of the signal output terminal to a pull-low control terminal. The discharging circuit turns on when a voltage of the pull-low control terminal is larger than a predetermined voltage level to discharge the switch control terminal to pull the switch control terminal to a second high level voltage. A second voltage pull-low circuit pulls the switch control terminal to a low level voltage when the output terminal voltage is larger than a reference voltage and does not have a glitch.

USB signal output circuit and operation method thereof having reverse current prevention mechanism

The present disclosure relates to a power circuit including a power supply circuit and a first control circuit. The power supply circuit is electrically connected to a power supply source and a power terminal for selectively providing power to the power terminal. The first control circuit is electrically connected to the power supply circuit and configured to receive a detection signal to enable or disable the power supply circuit. When the detection signal is enabled, the first control circuit provides a first enable signal to the power supply circuit, so that the power supply circuit provides power to the power terminal. When the detection signal is at the disable level, the first control circuit is configured to provide the first disable signal to the power supply circuit, so that the power supply circuit stops providing power from the power supply source to the power terminal.

Power circuit and driving method thereof

A switching device includes a first switch and a threshold voltage adjustment circuitry. The first switch is configured to be selectively turned on according to an enable signal, in order to connect a first pin to a second pin. The threshold voltage adjustment circuitry is configured to adjust a voltage level of a bulk terminal of the first switch according to the enable signal and a voltage provided from a power source. In response to the voltage being de-asserted, the threshold voltage adjustment circuitry is further configured to cut off a signal path between the bulk terminal and the power source.

Switching device and leakage current control method

A USB switching circuit includes a first multiplexer, a second multiplexer coupled with the first multiplexer through transmission paths, and a voltage regulation circuit coupled with the first and second multiplexers. The first multiplexer distributes first data signals to the transmission paths according to first control signals. The second multiplexer distributes a second data signal to the transmission paths according to second control signals. The voltage regulation circuit sets a maximum voltage and a minimum voltage of the first data signals to corresponding to a common voltage. The maximum voltage of the first data signals is not higher than a maximum voltage of the second control signals, or the minimum voltage of the first data signals is not lower than a minimum voltage of the second control signals. The first data signals and the second data signal are generated according to different communication protocols.

USB switching circuit and electronic apparatus having the same

Disclosed is a reference voltage generating circuit including a bandgap reference voltage generating circuit, a voltage controlled current source circuit, a current mirror circuit, an input voltage generating circuit, and a voltage controlled voltage source circuit. The bandgap reference voltage generating circuit generates a bandgap reference voltage. The voltage controlled current source circuit generates a reference current according to the bandgap reference voltage. The current mirror circuit generates a mirrored current according to the reference current. The input voltage generating circuit determines an input voltage according to the mirrored current. The voltage controlled voltage source circuit generates a reference voltage according to the input voltage. Accordingly, the reference voltage is generated with voltage-to-current conversion and voltage-to-voltage conversion so that the mirrored current can be accurate without being affected by the reference voltage and the reference voltage itself can be accurate.

Reference voltage generating circuit

Disclosed is a switch control circuit coupled between a switch control node and a voltage terminal. The switch control node is between an input circuit and a switch. The switch control circuit includes: an electronic component being turned on or off according to voltages of the switch control node and a control voltage node in a power-on state and preventing the voltage of the switch control node from being higher than a predetermined voltage in a power-off state; a control circuit outputting a control signal to the control voltage node in the power-on state and having no effective control over the voltage of the control voltage node in the power-off state; and a resistive component coupled between the control voltage node and voltage terminal. The electronic and resistive components function as at least a part of a leakage path to assist in turning off the switch in the power-off state.

Switch control circuit and switch circuit

The invention discloses a control circuit applied to a Universal Serial Bus (USB) which includes a first channel configuration pin and a second channel configuration pin. The control circuit includes: a first transistor having a first control terminal; a first resistor group coupled to the first channel configuration pin and the first transistor; a first Schottky diode having a first end and a second end, the first end being coupled to the first control terminal; a second transistor having a second control terminal; a second resistor group coupled to the second channel configuration pin and the second transistor; and a second Schottky diode having a third end and a fourth end, the third end being coupled to the second control terminal, and the fourth end being coupled to the second end of the first Schottky diode.

USB control circuit utilizing a single configuration pin

The present invention provides an interface circuit, wherein the interface circuit includes a switching circuit, an over-voltage detection circuit and a control signal generating circuit. In the operations of the interface circuit, the switching circuit is configured to receive an input signal from an input terminal, and selectively transmit the input signal to an internal circuit. The over-voltage detection circuit is configured to detect whether a voltage level of the input signal is greater than a threshold value, and accordingly generate at least one over-voltage signal. The control signal generating circuit is configured to generate a control signal according to said at least one over-voltage signal, to control the switching circuit to be in one of three or more states.

Interface circuit and method for controlling switching circuit within interface circuit

A switch circuit includes: a switching device control circuit receiving a first voltage and a second voltage, a first Type-I switching device coupled to the switching device control circuit and a first control voltage, a first Type-II switch element coupled to the switch control circuit and the first Type-I switch element, and a second Type-II switch element coupled to the first Type-I switch element and the first Type-II switch element. When the second voltage is higher than the first voltage, the switch control circuit turns on the first Type-II switch element in order to turn off the second Type-II switch element; and when the second voltage is higher than the first voltage, the first Type-I switch element is off.

Switch circuit and multiplexer applying the switch circuit

A differential switch circuit includes: a first transistor having a first terminal coupled with a first input terminal, a second terminal coupled with a first output terminal, and a control terminal coupled with a switch signal receiving terminal; a second transistor having a first terminal coupled with a second input terminal, a second terminal coupled with a second output terminal, and a control terminal coupled with the switch signal receiving terminal; a central switch element positioned between the control terminals of the first and second transistors; and a switch element control circuit for controlling the central switch element based on a switch signal. When the switch signal turns on the first and second transistors, the switch element control circuit turns off the central switch element, and when the switch signal turns off the first and second transistors, the switch element control circuit turns on the central switch element.

Differential switch circuit

The present disclosure illustrates a voltage regulator having wide common voltage operating range and an operating method thereof. The voltage regulator can solve a problem of the prior art that the excessive low or high common voltage easily causes the voltage regulator to operate abnormally. In addition, the voltage regulator completes the operation of boosting voltage by increasing additional switch transistors and error amplifiers without using a complex design, so that the lower common voltage can still satisfy with the operation condition of the voltage regulator to output the correct output voltage accordingly.

Voltage regulator having wide common voltage operating range and operating method thereof

An analog switch circuit is disclosed. The analog switch circuit includes a MOSFET and a control switch. The MOSFET includes a drain electrode, a source electrode, a gate electrode, and a body electrode. A gate bias is applied on the gate electrode to control whether the MOSFET is ON or OFF. The control switch includes a control terminal, a first terminal, a second terminal, and a third terminal. A control bias relating to the gate bias is applied to the control terminal so that the first terminal is connected to the second terminal when the MOSFET is ON, and the first terminal is connected to the third terminal when the MOSFET is OFF. The second terminal is connected to a first voltage source providing a first bias. The third terminal is connected to a second voltage source providing a second bias different from the first bias.

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Hsinchu, Taiwan

Leaf Chen