Low-dropout linear voltage stabilization source of digital-analog hybrid circuit

Abstract

The invention discloses a low-dropout linear voltage stabilization source of a digital-analog hybrid circuit. The low-dropout linear voltage stabilization source is applied to a reference source comprising a power switching module and a band-gap reference source. The low-dropout linear voltage stabilization source comprises a triode VT, a comparison amplifier A, a resistor R9 and a resistor R10. The collector electrode of the triode VT is connected with the output end of the low-dropout linear voltage stabilization source. The emitting electrode of the triode VT is connected with the input end of the low-dropout linear voltage stabilization source. The base electrode of the triode VT is connected with the output end of the comparison amplifier A. The negative input end of the comparison amplifier A is connected to the input end of the low-dropout linear voltage stabilization source. The positive input end of the comparison amplifier A is connected to a connection point between the resistor R9 and the resistor R10. The resistor R9 and the resistor R10 are connected in series between the output end of the low-dropout linear voltage stabilization source and the ground. According to the low-dropout linear voltage stabilization source, the performance can be improved in a certain aspect, for example, the power line and ground line interference is lowered, or a high supply voltage rejection ratio is realized, or the working stability is improved, or the load regulation rate is increased.

Description

technical field [0001] The invention relates to integrated circuit design technology, in particular to a digital-analog hybrid circuit (chip) and its auxiliary circuits. Background technique [0002] At present, digital-analog hybrid circuits are more and more widely used. Due to the existence of digital circuits and analog circuits at the same time, many factors must be considered during design. Here are some examples: [0003] One is that the grounding should be reasonable. In the digital-analog hybrid circuit, the digital signal is a noise source of the analog signal, which will bring ground bounce noise and power disturbance to the entire circuit. These noises and interferences are coupled into the analog circuit, which will affect the working performance of the analog circuit. Since most of the interference sources are generated through the ground wire and the power wire, and the noise interference caused by the ground wire is the largest, the design of the ground wi...

AI Technical Summary

Problems solved by technology

The traditional bandgap reference source needs to use the feedback loop formed by the operational amplifier to realize the stable output of the voltage reference source. Due to the limitation of the bandwidth and gain of the operational amplifier itself, the fluctuation of the power supply voltage cannot be achieved within a certain bandwidth range (especially in the middle frequency band). is well suppressed, thereby affecting the output signal quality of the reference voltage source

In addition, in the traditional bandgap reference circuit, the output voltage VBE is about 1.25V, which limits the application of the power supply voltage below 1V

The subsequent improved enhanced bandgap reference source circuit structure uses a pre-voltage source to supply power to the bandgap reference source alone, which improves the power supply voltage rejection ratio to a certain extent, but the improved circuit structure increases static power consumption and chip area.

[0005] In addition, there are other deficiencies in existing digital-analog hybrid circuits, which need to be optimized to improve performance

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