The Experts below are selected from a list of 42 Experts worldwide ranked by ideXlab platform
Xue Liying - One of the best experts on this subject based on the ideXlab platform.
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circuit and method for detecting direct current power ground insulation Resistor
2013Co-Authors: Zhang Yanhu, Wan Like, Hu Bing, Shen Tan, Deng Jun, Xue LiyingAbstract:The invention relates to a circuit and a method for detecting a direct-current power ground insulation Resistor. The circuit comprises Resistors R1 to R5 and switches S1 to S2, wherein the Resistors R1 and R3 have the same resistance value; the Resistors R2 and R4 have the same resistance value; one end of the Resistor R2 is connected to an anode of a direct-current power supply through the Resistor R1, and the other end of the Resistor R2 is grounded through the switch S1; the Resistors R1 and R2 and the switch S1 form a first detection branch circuit; one end of the Resistor R4 is connected to a cathode of the direct-current power supply through the Resistor R3, and the other end of the Resistor R4 is grounded through the switch S2; the Resistors R3 and R4 and the switch S2 form a second detection branch circuit; and the Resistor R5 is connected with the first detection branch circuit or the second detection branch circuit in parallel. The circuit has the advantages as follows: when resistance values of positive and negative ground insulation Resistors R+ and R- of the direct-current power supply are reduced in a uniform amplitude way or close to each other, the resistance values of the Resistors R+ and R- can be still detected, and detection precision of the Resistors R+ and R- can be also guaranteed.
Jack R. Smith - One of the best experts on this subject based on the ideXlab platform.
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A Morse Code Reader
Programming the PIC Microcontroller with MBASIC, 2020Co-Authors: Jack R. SmithAbstract:This chapter describes the use of PIC for reading Morse. A phase-locked loop and an adaptive algorithm to account for timing variations in hand sending are presented in the chapter. The XR-2211 is the receiving half of a modem device; it receives frequency shift keyed data signals and translates the two tones into logic level output signals. An auxiliary function built into the XR-2211, however, is tone detection to determine whether the modem is currently receiving a signal and that is the part used in Morse decoder circuit. The audio input signal is coupled to the XR-2211's internal preamplifier through a 0.1 μF blocking capacitor. The preamp's output feeds two phase detectors, one for loop control and a quadrature phase detector for tone detection. The lock detector comparator is of open collector design and hence requires a pull-up Resistor. R2/D 1 pulls up the comparator output and provides, through LED D1, a visual indication of tone detection. To reduce the effect of tone decoder output glitches, the circuit adds an RC filter.
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AC Power Control
Programming the PIC Microcontroller with MBASIC, 2020Co-Authors: Jack R. SmithAbstract:This chapter explores controlling 120 V AC power-line loads with a PIC. The principal AC power-control device is the triac. The triac is a member of the thyristor family, along with the programmable unijunction transistor (PUT), the bidirectional diode thyristor (diac), and the silicon controlled rectifier (SCR). The common feature among all members of the thyristor family is that they have conducting and nonconducting states. Most thyristors require current injection or current removal from a gate connection to become conducting. Thyristor construction provides inherent internal positive feedback. Latching current is the minimum current that the triac must carry to latch into conducting mode once the gate drive is removed. The direct correlation between the gate sensitivity and the rated is obvious, and as the device is made more sensitive to permit lower gate current, it becomes more sensitive to false gate triggering. The power control board also provides mounting for the opto-triac coupler and the triac. Resistor R2 and LED D1 on the prototype board are in series with the LED contained within the opto-triac coupler. D1 provides a visual check of triac trigger pulses, while R2 limits the current through the LEDs to approximately 15 mA.
Lin Yi - One of the best experts on this subject based on the ideXlab platform.
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a wien brigde chaotic oscillator based on a firs order generalized memory Resistor
2015Co-Authors: Bao Bocheng, Yu Jingjing, Yu Qing, Hu Fengwei, Jiang Pan, Lin YiAbstract:The invention discloses a wien-bridge chaotic oscillator based on a firs-order generalized memory Resistor. The wien-bridge chaotic oscillator based on a firs-order generalized memory Resistor comprises a capacitor C1, a capacitor C2, a capacitor C3, a inductor L, a Resistor R1, a Resistor R2, a Resistor R3, a Resistor R4, an operational amplifier U1, and the memory Resistor M comprised of a diode bridge cascade RC filter; wherein, the memory Resistor M comprised of the diode bridge cascade RC filter comprises a diode D1, a diode D2, a diode D3, a diode D4, a Resistor R0, and a capacitor C0. The wien-bridge chaotic oscillator based on a firs-order generalized memory Resistor according to the invention is simple in structure, and through regulating reference values of elements of the circuit, the wien-bridge chaotic oscillator can exhibit different chaotic characteristics and obtain a chaotic behavior with complex dynamic characteristics. The memory Resistor equivalent circuit according to the invention has no limitation of being grounded, i.e. the equivalent input end requires no ground processing and enables to be connected in series into the existing oscillating circuit. The dynamic characteristics of the memory Resistor chaotic circuit according to the invention do not depend on the initial state, and the complex nonlinear physical phenomenon is avoided effectively.
Wang Lidan - One of the best experts on this subject based on the ideXlab platform.
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memristor based hyperchaotic system realization circuit
2013Co-Authors: Yin Weihong, Wang LidanAbstract:The utility model discloses a Memristor-based hyperchaotic-system realization circuit and the key is that the circuit comprises a multiplier M1. An input terminal of the multiplier M1 is connected with output terminals of an operational amplifier U3 and an operational amplifier U7, and an output terminal of the M1 is connected with a Resistor R9. An input terminal of the multiplier M2 is connected with output terminals of operational amplifiers U2 and U5 and an output terminal of the M2is connected with R13. A Resistor R1 is connected between an input terminal of an operational amplifier U1 and an output terminal of an operational amplifier U13. A Resistor R2 is connected between the input terminal of an operational amplifier U1 and the output terminal of the operational amplifier U5. The realization circuit provided by the utility model is simple and convenient for integration and plays a large promotion effect on promoting chaos system industrialization in information processing and secret communication. Generated time-domain chaos signals can be taken to be chaos signal sources of secret communication and also can be utilized in image encryption or random bit generators.
Zhang Yanhu - One of the best experts on this subject based on the ideXlab platform.
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circuit and method for detecting direct current power ground insulation Resistor
2013Co-Authors: Zhang Yanhu, Wan Like, Hu Bing, Shen Tan, Deng Jun, Xue LiyingAbstract:The invention relates to a circuit and a method for detecting a direct-current power ground insulation Resistor. The circuit comprises Resistors R1 to R5 and switches S1 to S2, wherein the Resistors R1 and R3 have the same resistance value; the Resistors R2 and R4 have the same resistance value; one end of the Resistor R2 is connected to an anode of a direct-current power supply through the Resistor R1, and the other end of the Resistor R2 is grounded through the switch S1; the Resistors R1 and R2 and the switch S1 form a first detection branch circuit; one end of the Resistor R4 is connected to a cathode of the direct-current power supply through the Resistor R3, and the other end of the Resistor R4 is grounded through the switch S2; the Resistors R3 and R4 and the switch S2 form a second detection branch circuit; and the Resistor R5 is connected with the first detection branch circuit or the second detection branch circuit in parallel. The circuit has the advantages as follows: when resistance values of positive and negative ground insulation Resistors R+ and R- of the direct-current power supply are reduced in a uniform amplitude way or close to each other, the resistance values of the Resistors R+ and R- can be still detected, and detection precision of the Resistors R+ and R- can be also guaranteed.