Differential amplifier with temp compensation function

Abstract

A different amplifier with temp. compensation function includes two differential amplifiers, one is with feedback resistance, and gain and direct proportion with temp. the other is connected with the back of the first one, and without feedback resistance and reciprocal with temp. The temp. compensation are by gain and distortion of the amplifiers.

Description

technical field [0001] The invention relates to a differential amplifier without a feedback resistor and having a temperature compensation function capable of temperature compensating the gain and distortion of the differential amplifier. Background technique [0002] figure 1 To show the existing differential amplifier circuit diagram without feedback resistors, in the figure, Vcc is the power supply, GND is the ground, RL is the load resistor, Q1 and Q2 are transistors, and C1 is the constant current source [0003] The operation thereof will be described below. [0004] The differential input current ΔI can be represented by the following equation (1). [0005] ΔI=I0·tanh(ΔV / 2V T ) (1) [0006] In the formula, I0 is the current of constant current source C1, ΔV is the differential input voltage, V T =kT / g, k is Boltzmann's constant, T is absolute temperature, and q is electric charge. [0007] If the above formula (1) is expanded as a series, the f...

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Problems solved by technology

[0012] In this way, in a differential amplifier without a feedback resistor, there is a problem that the gain and distortion vary depending on the absolute temperature T

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