Log amplifier with temperature compensation function

Abstract

The invention provides a logarithmic amplifier with a temperature compensation function, the logarithmic amplifier includes a basic logarithmic circuit, a temperature compensation circuit, a temperature compensation auxiliary circuit and a PMOS tube grid voltage control loop; the basic logarithmic circuit, for the input The signal is logarithmically converted, and this logarithmic signal has a coefficient proportional to the absolute temperature; the temperature compensation circuit is used to eliminate the temperature coefficient of the above logarithmic signal; the temperature compensation auxiliary circuit is used to eliminate the temperature compensation circuit in the Eliminate the DC offset that changes with temperature during the process of eliminating the temperature coefficient, and finally obtain a logarithmic signal that does not change with temperature; the PMOS tube gate voltage control loop is used to realize the temperature control of the temperature compensation circuit and the temperature compensation auxiliary circuit . In this way, the complexity of the system caused by the traditional on-chip external thermistor and digital correction to eliminate the influence of temperature changes is avoided, which is conducive to improving the integration of the application system.

Description

technical field [0001] The invention relates to a logarithmic amplifier with temperature compensation function implemented in the form of an integrated circuit. Taking advantage of the fact that the on-resistance of metal-oxide transistors operating in the linear region is mainly controlled by their gate-source voltage, the absolute temperature-proportional nature of the bias current from the bandgap reference and the basic logarithmic amplifier The characteristic that the coefficient is proportional to the absolute temperature is offset, and the subtractor is used to eliminate the DC offset that is proportional to the absolute temperature introduced by the above compensation method, and the temperature compensation is completely realized on-chip. Background technique [0002] Logarithmic amplifiers have always played an important role in signal compression and computing. Even though digital integrated circuits have almost entirely replaced log amps in computing application...

AI Technical Summary

Problems solved by technology

Although received signal strength detection can be implemented in the digital domain, the steps are complicated, the detection range is small, and the accuracy is poor

At present, the received signal strength detection is mainly realized by the method of analog circuit, but the detection result of the received signal strength detector implemented by most analog circuits is linear with the input signal amplitude

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