5results about How to "Improve phase margin" patented technology

The utility model relates to electronic circuit technical field, concretely relates to an adjustable constant current source drive circuit, in the drive circuit, when the second input end of adjusting circuit receives voltage signal, current sampling circuit perceives the current of load and forms voltage difference at both ends, feedback circuit gathers voltage difference and forms feedback signal input to adjusting circuit, and adjusting circuit exports adjusting signal according to feedback signal and received voltage signal, and the process of adjusting signal and feedback signal, gathering voltage difference, repeatedly perceiving current is repeated until feedback signal and voltage signal are consistent, and load current reaches stable value. The adjustable constant current source drive circuit provided by the utility model embodiment, through the setting of current sampling circuit, feedback circuit, adjusting circuit and control circuit, not only realizes the closed loop control and accurate adjustment of load current, and through double -end sampling, avoids the problem of system power supply noise and unstable influence introduced by single -end sampling.

The application discloses a novel three-stage operational amplifier indirect frequency compensation circuit and belongs to the electronic circuit field. A , a second resistor R B , a first capacitor C C1 , a second capacitor C C2 , NMOS tubes MN1-MN8 and PMOS tubes MP1-PMOS tubes MP6; the NMOS tubes MN1-MN5 and the PMOS tubes MP1-PMOS tubes MP2 are a first gain stage of an operational amplifier; the NMOS tubes MN6-MN7 and the PMOS tubes MP3-PMOS tubes MP5 are a second gain stage of the operational amplifier; the NMOS tube MN8 and the PMOS tube MP6 are a third gain stage; the second resistor R B and the first capacitor C C1 , the first resistor R A and the second capacitor C C2 are an indirect frequency compensation network. The application can greatly improve the loop phase margin and the circuit transient stability under the condition of using a smaller compensation capacitor by generating a zero point located in the left half plane to offset a sub-pole in the operational amplifier loop.

The invention discloses a high dropout linear regulator. According to the high-voltage-difference linear voltage regulator, the second end of a power tube is connected with the first end of a zero point compensation module, and a zero point generated by the zero point compensation module compensates a pole of the output end of the high-voltage-difference linear voltage regulator. The offset voltage calibration module samples the current of the power tube and generates a calibration current according to the sampled current so as to calibrate the feedback voltage. The output voltage feedback module generates feedback voltage according to the output voltage of the power tube to the inverted input end of the error amplification module, reference voltage is connected to the in-phase input end of the error amplification module, and the error amplification module adjusts the control end voltage of the power tube according to the reference voltage and the feedback voltage so as to adjust the output voltage of the power tube. According to the technical scheme, the application range of the load capacitor is widened, the application flexibility of the high-voltage-difference linear voltage regulator is improved, and the precision of the output voltage of the high-voltage-difference linear voltage regulator is improved.

The invention relates to the technical field of analog integrated circuits, in particular to a high-precision temperature sensor temperature-sensing front-end circuit based on a chopping technology, and aims to solve the problems of low-frequency 1 / f noise, operational amplifier input offset voltage drift, band-gap reference temperature drift, limited output driving capability and the like existing at the front end of a traditional temperature sensor. The front-end circuit comprises a chopping band-gap reference source circuit, a chopping buffer circuit and a two-phase non-overlapping clock generation circuit, wherein the chopping band-gap reference source circuit adopts a parasitic bipolar PNP transistor with an emitter junction area ratio of 8: 1 as a temperature sensing device, and a high-gain chopping folded cascode operational amplifier is embedded in the chopping band-gap reference source circuit; and stable positive temperature coefficient voltage and low-temperature drift reference voltage are generated. Noise and maladjustment are inhibited from the system architecture level, the temperature measurement precision can reach the sub-degree centigrade level, the loading capacity is high, the method is achieved based on the standard CMOS technology, a special technology and complex temperature calibration are not needed, and the method has the advantages of being low in cost, high in stability and large-scale integration.

The invention belongs to the technical field of power electronics, and particularly discloses a grid-connected inverter optimization compensation method for inhibiting phase-locked loop influence and broadband resonance. According to the invention, the disturbance transfer function is calculated based on the dynamic model of the phase-locked loop, the associated compensation signal is injected into the target axis signal, and the low-frequency control disturbance dynamically introduced by the phase-locked loop is counteracted; superposing the output compensation signal to an associated compensation signal; and according to the composite compensation signal, the output impedance characteristic of the grid-connected inverter in the middle-high frequency band is remodeled. According to the mode, the low-frequency disturbance dynamically introduced by the phase-locked loop is counteracted by injecting the associated compensation signal, and on the basis, an optimization compensation link is newly added, and the output compensation signal is remodeled in the middle-high frequency band, so that the low-frequency disturbance of the phase-locked loop is eliminated on the basis of not changing the structure of the phase-locked loop and main control parameters. And the low-frequency stability and medium-high frequency resonance suppression of the inverter are synergistically improved, so that the wide-frequency-band stability and the electric energy quality of the grid-connected system under the weak power grid condition are effectively enhanced.