Abstract: The present application discloses a power-on-reset circuit, which optimizes a hysteresis circuit and a reset signal generation circuit, and introduces a seventh PMOS transistor as a switch transistor to achieve the differentiation of control voltages at a gate end of a first NMOS transistor during powering-on and off. A voltage rise detection point is determined by a partial voltage of a resistor during powering-on, while a voltage fall detection point is directly determined by a power supply voltage during powering-off. Such differentiation may achieve a significant separation between the voltage rise detection point and the voltage fall detection point, reducing the voltage fall detection point to near a threshold voltage of the first NMOS transistor, and meeting the demand for a lower voltage fall detection point, which is consistent with a practical application of the power-on-reset circuit in an MCU.

Abstract: The present application discloses a multi-level voltage detector circuit. The voltage dividing circuit includes a first resistor string and a second circuit. The first resistor string is formed by n+1 voltage dividing resistors connected in series and outputs n divisional voltages. The second circuit provides n lower voltage dividing resistors. A kth lower voltage dividing resistor detects kth rise and fall detection points of a power supply voltage. When the kth rise detection point is detected, the second circuit provides a kth lower voltage dividing resistor and short-circuits the kth lower voltage dividing resistor. When the kth fall detection point is detected, the second circuit provides the kth lower voltage dividing resistor to a position between a second end of an nth voltage dividing resistor and the ground. As the value of k increases, the resistance of the kth lower voltage dividing resistor decreases.

Abstract: The present application provides a distributed LDO regulator structure without an external capacitor. The structure includes one CORE module; and one or more POWER modules driven by one of the CORE modules. The CORE module comprises a mirror source voltage generating circuit and a built-in LDO regulator circuit. An output end of an operational amplifier and a gate of the sixth PMOS together serve as a control voltage end of the POWER module. A negative input end of the operational amplifier is connected to a drain of the fifth PMOS and a source of the sixth PMOS by means of a first resistor, wherein a connection end serves as an output end of the built-in LDO regulator circuit. POWER modules having the same output voltage are connected to each other in parallel.

Abstract: The present application provides a distributed LDO regulator structure without an external capacitor. The structure includes one CORE module; and one or more POWER modules driven by one of the CORE modules. The CORE module comprises a mirror source voltage generating circuit and a built-in LDO regulator circuit. An output end of an operational amplifier and a gate of the sixth PMOS together serve as a control voltage end of the POWER module. A negative input end of the operational amplifier is connected to a drain of the fifth PMOS and a source of the sixth PMOS by means of a first resistor, wherein a connection end serves as an output end of the built-in LDO regulator circuit. POWER modules having the same output voltage are connected to each other in parallel.

Abstract: The present invention discloses a power supply powering-on structure, which comprises an LDO module, a bandgap reference module, a voltage detection module, a bias module and a switch module; the working voltage of the LDO module, the voltage detection module and the bias module adopts external power supply voltage; the working voltage of the bandgap reference module adopts LDO output voltage; the switch module provides switching connection between the output of the bias module and the output of the bandgap reference module for a reference voltage input end and a bias current input end of the LDO module. The present invention can adopt internal power supply voltage to supply power to the bandgap reference module and can also solve the problem that the internal power supply voltage restricts the powering-on and starting of the bandgap reference module.

Abstract: The present invention discloses a power supply powering-on structure, which comprises an LDO module, a bandgap reference module, a voltage detection module, a bias module and a switch module; the working voltage of the LDO module, the voltage detection module and the bias module adopts external power supply voltage; the working voltage of the bandgap reference module adopts LDO output voltage; the switch module provides switching connection between the output of the bias module and the output of the bandgap reference module for a reference voltage input end and a bias current input end of the LDO module. The present invention can adopt internal power supply voltage to supply power to the bandgap reference module and can also solve the problem that the internal power supply voltage restricts the powering-on and starting of the bandgap reference module.

Abstract: A demodulation system for 3D-matrix multi-channel fiber optic sensing includes a wavelength swept optical source that generates an incident light, an optical frequency domain reflector and a balanced detector connected with the wavelength swept optical source through a fiber circulator. The optical frequency domain reflector includes a first optical path and a second optical path with a frequency shifter arranged on one or both of the optical paths. The optical frequency domain reflector outputs incident light to an optical switch module. The optical switch module selectively transmits the incident light to a sensor network as well as transmits the reflection light from the sensor network to the optical frequency domain reflector.

Abstract: An optical fiber rotary squeezer polarization controller, comprising a base, a left bracket and a right bracket respectively mounted at both ends of the base, characterized in that a shaft is rotatably mounted between the left bracket and the right bracket, the shaft having a through channel cut therein lengthwise for placement of an optical fiber, the shaft further being mounted with a squeezing apparatus corresponding to the channel. The present invention has altered the means by which an optical fiber is fixed onto the prior-art polarization controllers and has eliminated the clamps at both ends of the optical fiber. The shaft carries the squeezing apparatus to rotate to any desired angles while the optical fiber remains stationary under the effect of its own tension. As the optical fiber extends outwardly from either end of the shaft, it is restrained by its own tension and, therefore, will not rotate along with the shaft.

Abstract: An optical fiber rotary squeezer polarization controller, comprising a base, a left bracket and a right bracket respectively mounted at both ends of the base, characterized in that a shaft is rotatably mounted between the left bracket and the right bracket, the shaft having a through channel cut therein lengthwise for placement of an optical fiber, the shaft further being mounted with a squeezing apparatus corresponding to the channel. The present invention has altered the means by which an optical fiber is fixed onto the prior-art polarization controllers and has eliminated the clamps at both ends of the optical fiber. The shaft carries the squeezing apparatus to rotate to any desired angles while the optical fiber remains stationary under the effect of its own tension. As the optical fiber extends outwardly from either end of the shaft, it is restrained by its own tension and, therefore, will not rotate along with the shaft.

Abstract: A demodulation system for 3D-matrix multi-channel fiber optic sensing includes a wavelength swept optical source that generates an incident light, an optical frequency domain reflector and a balanced detector connected with the wavelength swept optical source through a fiber circulator. The optical frequency domain reflector includes a first optical path and a second optical path with a frequency shifter arranged on one or both of the optical paths. The optical frequency domain reflector outputs incident light to an optical switch module. The optical switch module selectively transmits the incident light to a sensor network as well as transmits the reflection light from the sensor network to the optical frequency domain reflector.

Abstract: The specification describes an improved optical fiber design in which the criteria for high performance in a Raman amplified optical system, such as moderate effective area, moderate dispersion, low dispersion slope, and selected zero dispersion wavelength, are simultaneously optimized. In preferred embodiments of the invention, the dispersion characteristics are deliberately made selectively dependent on the core radius. This allows manufacturing variability in the dispersion properties, introduced in the core-making process, to be mitigated during subsequent processing steps.

Abstract: The specification describes an improved optical fiber design in which the criteria for high performance in a Raman amplified optical system, such as moderate effective area, moderate dispersion, low dispersion slope, and selected zero dispersion wavelength, are simultaneously optimized. In preferred embodiments of the invention, the dispersion characteristics are deliberately made selectively dependent on the core radius. This allows manufacturing variability in the dispersion properties, introduced in the core-making process, to be mitigated during subsequent processing steps.

Abstract: The specification describes an improved optical fiber design in which the criteria for high performance in a Raman amplified optical system, such as moderate effective area, moderate dispersion, low dispersion slope, and selected zero dispersion wavelength, are simultaneously optimized. In preferred embodiments of the invention, the dispersion characteristics are deliberately made selectively dependent on the core radius. This allows manufacturing variability in the dispersion properties, introduced in the core-making process, to be mitigated during subsequent processing steps.

Abstract: The specification describes an improved optical fiber design in which the criteria for high performance in a Raman amplified optical system, such as moderate effective area, moderate dispersion, low dispersion slope, and selected zero dispersion wavelength, are simultaneously optimized. In preferred embodiments of the invention, the dispersion characteristics are deliberately made selectively dependent on the core radius. This allows manufacturing variability in the dispersion properties, introduced in the core-making process, to be mitigated during subsequent processing steps.

Abstract: The specification describes an improved optical fiber design in which the criteria for high performance in a Raman amplified optical system, such as moderate effective area, moderate dispersion, low dispersion slope, and selected zero dispersion wavelength, are simultaneously optimized. In preferred embodiments of the invention, the dispersion characteristics are deliberately made selectively dependent on the core radius. This allows manufacturing variability in the dispersion properties, introduced in the core-making process, to be mitigated during subsequent processing steps.