Abstract: Illustrative surge protectors and surge protection methods provide accurate clamp level control during voltage transients and surge events. One illustrative surge protector includes: a shunt transistor having a source coupled to ground and a drain coupled to a conductor at a supply voltage; and an operational amplifier having: an output coupled to a gate of the shunt transistor, an inverting input coupled to a reference voltage Vref, and a noninverting input coupled to receive a sense voltage, the sense voltage being a fixed fraction f of the supply voltage, the operational amplifier being configured to drive the shunt transistor to shunt any excess current when the supply voltage reaches a clamp voltage Vc=Vref/f.

Abstract: In a general aspect, a discharge circuit for discharging a voltage from a USB connector pin can include a discharge load configured to discharge the voltage from the pin. The discharge circuit can also include a first control circuit configured to adjust a magnitude of the discharge load during discharging, such that power consumption is less than or equal to a discharge power limit, and a discharge time is less than or equal to a discharge time limit. The discharge circuit can further include a second control circuit configured to detect whether the voltage of the pin is changed based on a first reference voltage during discharging and adjust the magnitude of the discharge load in response to the change in the voltage of the pin, such that a slew rate of the voltage is less than or equal to a slew rate limit.

Abstract: This document discusses, among other things, a signal receiving circuit, configured to receive an input voltage signal. The signal receiving circuit can comprise an input voltage regulating circuit and a comparing circuit. The input voltage regulating circuit can carry out a waveform pre-regulation for the input voltage signal to obtain a first voltage signal, and the comparing circuit can compare the first voltage signal with a second voltage signal, and output a comparison voltage signal having a pulse width that satisfies a first predetermined condition indicative that the input voltage signal is correctly identifiable. The present document further discusses a signal detecting circuit and a signal receiving method.

Abstract: According to an aspect, a switch circuit for a Universal Serial Bus (USB) connector device includes a main transistor configured to be activated during a normal operation of the switch circuit, a first voltage generator circuit configured to generate a voltage on a high local rail during an overvoltage event, a second voltage generator circuit configured to generate a voltage on a low local rail during the overvoltage event, where the low local rail is connected to a bulk of the main transistor, and a clamp circuit connected to the high local rail between the first voltage generator circuit and a gate of the main transistor, where the clamp circuit is configured to clamp the voltage between the high local rail and the gate of the main transistor during the overvoltage event.

Abstract: According to an aspect, an overvoltage protection circuit includes a bias current generator configured to generate a bias current, and a current comparator configured to receive the bias current and a voltage associated with a data terminal of a connector. The current comparator includes a transistor. The transistor is configured to activate based on a level of the voltage associated with the data terminal. The current comparator is configured to compare a current of the transistor with the bias current. The overvoltage protection circuit includes an output circuit configured to generate an overvoltage protection signal in response to the current of the transistor being greater than the bias current.

Abstract: In a general aspect, a circuit can include a reference current generator configured to generate a first current signal representative of a threshold voltage. The circuit can also include a current comparator configured to mirror the first current signal, generate a second current signal representative of a received voltage and compare the second current signal to the first current signal. The current comparator can also be configured to provide a detection signal at a first logic value to indicate that the received voltage is below the threshold voltage when the comparison of the second current signal with the first current signal indicates that the received voltage is less than the threshold voltage.

Abstract: According to an aspect, a switch circuit for a Universal Serial Bus (USB) connector device includes a main transistor configured to be activated during a normal operation of the switch circuit, a first voltage generator circuit configured to generate a voltage on a high local rail during an overvoltage event, a second voltage generator circuit configured to generate a voltage on a low local rail during the overvoltage event, where the low local rail is connected to a bulk of the main transistor, and a clamp circuit connected to the high local rail between the first voltage generator circuit and a gate of the main transistor, where the clamp circuit is configured to clamp the voltage between the high local rail and the gate of the main transistor during the overvoltage event.

Abstract: In a general aspect, a discharge circuit for discharging a voltage from a USB connector pin can include a discharge load configured to discharge the voltage from the pin. The discharge circuit can also include a first control circuit configured to adjust a magnitude of the discharge load during discharging, such that power consumption is less than or equal to a discharge power limit, and a discharge time is less than or equal to a discharge time limit. The discharge circuit can further include a second control circuit configured to detect whether the voltage of the pin is changed based on a first reference voltage during discharging and adjust the magnitude of the discharge load in response to the change in the voltage of the pin, such that a slew rate of the voltage is less than or equal to a slew rate limit.

Abstract: A circuit for power supply protection comprising a first n-channel Metal Oxide Semiconductor Field Effect Transistor (nMOSFET) and a first p-channel Metal Oxide Semiconductor Field Effect Transistor (pMOSFET) each having a drain terminal coupled to an input voltage, a second nMOSFET and a second pMOSFET having drain terminals coupled to an output voltage and sources coupled to a sources of the first and second nMOSFET, respectively, and a control circuit. The control circuit turns the nMOSFETs off and the pMOSFETs on when the input voltage has a voltage value greater than zero and less than a predetermined positive limit, operates the nMOSFETs in a saturation mode and turns the pMOSFETs off when the input voltage has a voltage value greater than the predetermined positive limit, and turn the nMOSFETs and pMOSFETs off when the input voltage has a voltage value less than zero.

Abstract: According to an aspect, an overvoltage protection circuit includes a bias current generator configured to generate a bias current, and a current comparator configured to receive the bias current and a voltage associated with a data terminal of a connector. The current comparator includes a transistor. The transistor is configured to activate based on a level of the voltage associated with the data terminal. The current comparator is configured to compare a current of the transistor with the bias current. The overvoltage protection circuit includes an output circuit configured to generate an overvoltage protection signal in response to the current of the transistor being greater than the bias current.

Abstract: This document discusses, among other things, a discharge circuit for a USB connector configured to discharge a voltage of a pin (e.g., a VBUS pin) of the USB connector. The discharge circuit can include a discharge load to discharge the voltage of the pin; a first control circuit to adjust the magnitude of the discharge load during discharging, such that power consumption generated by the discharge load meets a first preset condition and a discharge time is within a first preset range, the first preset condition indicating that the generated power consumption does not trigger Over Temperature Protection (OTP); and a second control circuit to detect whether the voltage of the pin is changed based on a reference voltage during discharging and adjust the magnitude of the discharge load in response to the change, such that a slew rate of the voltage of the first pin is within a second preset range.

Abstract: In a general aspect, a circuit can include a reference current generator configured to generate a first current signal representative of a threshold voltage. The circuit can also include a current comparator configured to mirror the first current signal, generate a second current signal representative of a received voltage and compare the second current signal to the first current signal. The current comparator can also be configured to provide a detection signal at a first logic value to indicate that the received voltage is below the threshold voltage when the comparison of the second current signal with the first current signal indicates that the received voltage is less than the threshold voltage.

Abstract: This document discusses, among other things, a signal receiving circuit, configured to receive an input voltage signal. The signal receiving circuit can comprise an input voltage regulating circuit and a comparing circuit. The input voltage regulating circuit can carry out a waveform pre-regulation for the input voltage signal to obtain a first voltage signal, and the comparing circuit can compare the first voltage signal with a second voltage signal, and output a comparison voltage signal having a pulse width that satisfies a first predetermined condition indicative that the input voltage signal is correctly identifiable. The present document further discusses a signal detecting circuit and a signal receiving method.

Abstract: This document discusses, among other things, a signal receiving circuit, configured to receive an input voltage signal. The signal receiving circuit can comprise an input voltage regulating circuit and a comparing circuit. The input voltage regulating circuit can carry out a waveform pre-regulation for the input voltage signal to obtain a first voltage signal, and the comparing circuit can compare the first voltage signal with a second voltage signal, and output a comparison voltage signal having a pulse width that satisfies a first predetermined condition indicative that the input voltage signal is correctly identifiable. The present document further discusses a signal detecting circuit and a signal receiving method.

Abstract: A circuit for power supply protection comprising a first n-channel Metal Oxide Semiconductor Field Effect Transistor (nMOSFET) and a first p-channel Metal Oxide Semiconductor Field Effect Transistor (pMOSFET) each having a drain terminal coupled to an input voltage, a second nMOSFET and a second pMOSFET having drain terminals coupled to an output voltage and sources coupled to a sources of the first and second nMOSFET, respectively, and a control circuit. The control circuit turns the nMOSFETs off and the pMOSFETs on when the input voltage has a voltage value greater than zero and less than a predetermined positive limit, operates the nMOSFETs in a saturation mode and turns the pMOSFETs off when the input voltage has a voltage value greater than the predetermined positive limit, and turn the nMOSFETs and pMOSFETs off when the input voltage has a voltage value less than zero.

Abstract: Systems and methods are disclosed, including a USB interface detector, a detection method, a USB connector, and an electronic device. The detection method may be applicable to the USB connector mounted in the electronic device. According to an operation mode of the electronic device, a first pin and a second pin in the USB interface can be pulled up or pulled down. After the pull up or the pull down, a voltage change at the first and second pins are detected. If the voltage changes cross a reference voltage, an instruction related to attachment or detachment with a second device can be provided.

Abstract: This document discusses, among other things, a discharge circuit for a USB connector configured to discharge a voltage of a pin (e.g., a VBUS pin) of the USB connector. The discharge circuit can include a discharge load to discharge the voltage of the pin; a first control circuit to adjust the magnitude of the discharge load during discharging, such that power consumption generated by the discharge load meets a first preset condition and a discharge time is within a first preset range, the first preset condition indicating that the generated power consumption does not trigger Over Temperature Protection (OTP); and a second control circuit to detect whether the voltage of the pin is changed based on a reference voltage during discharging and adjust the magnitude of the discharge load in response to the change, such that a slew rate of the voltage of the first pin is within a second preset range.

Abstract: This document discusses, among other things, a signal receiving circuit, configured to receive an input voltage signal. The signal receiving circuit can comprise an input voltage regulating circuit and a comparing circuit. The input voltage regulating circuit can carry out a waveform pre-regulation for the input voltage signal to obtain a first voltage signal, and the comparing circuit can compare the first voltage signal with a second voltage signal, and output a comparison voltage signal having a pulse width that satisfies a first predetermined condition indicative that the input voltage signal is correctly identifiable. The present document further discusses a signal detecting circuit and a signal receiving method.

Abstract: Systems and methods are disclosed, including a USB interface detector, a detection method, a USB connector, and an electronic device. The detection method may be applicable to the USB connector mounted in the electronic device. According to an operation mode of the electronic device, a first pin and a second pin in the USB interface can be pulled up or pulled down. After the pull up or the pull down, a voltage change at the first and second pins are detected. If the voltage changes cross a reference voltage, an instruction related to attachment or detachment with a second device can be provided.