A Concentrated Bandgap Reference Circuit under High and Low Temperature

Abstract

The invention discloses a bandgap reference circuit distributed in a concentrated mode at high temperature and low temperature. The bandgap reference circuit distributed in the concentrated mode at high temperature and low temperature comprises bandgap reference circuit bodies, a temperature detector and a gating logic module. The bandgap reference circuit bodies are used for outputting a bandgap reference voltage vBGR. The temperature detector is used for detecting the temperature of an environment where the bandgap reference circuit bodies are located and outputting a first signal to the gating logic module when a measured temperature value is larger than or equal to a threshold value and outputting a second signal to the gating logic module when the measured temperature value is smaller than the threshold value. The gating logic module is used for transmitting first adjusting codes to the bandgap reference circuit bodies when receiving the first signal and transmitting second adjusting codes to the bandgap reference circuit bodies when receiving the second signal. The adjusting codes corresponding to the bandgap reference circuit bodies at high temperature and low temperature are found, and proper adjusting codes are selected according to the dynamic state of an external temperature value so that the purpose that bandgap voltage output values are distributed nearby a target value in a quite concentrated mode at high temperature and low temperature can be achieved.

Description

[0001] 【Technical field】 [0002] The invention relates to the technical field of integrated circuits, in particular to a bandgap reference circuit. [0003] 【Background technique】 [0004] At present, most of the bandgap reference circuits adopt the traditional voltage-type structure, and the design ensures that the output voltage of the bandgap reference varies with temperature, process and power supply voltage within a certain range. The basic principle of its operation is as follows figure 1 As shown, it includes operational amplifier controls, three diodes (D1, D2, D3), two resistors R2, R3 connected in series to the two diodes (D2, D3), and three MOS transistors. The absorbed bandgap reference circuit adds a voltage with a positive temperature coefficient and a voltage with a negative temperature coefficient to obtain a voltage with a zero temperature coefficient. [0005] In the front-end test, first measure the voltage value of the bandgap reference at high temperatur...

AI Technical Summary

Problems solved by technology

If the traditional front-end trim method is used, the output voltage can only be adjusted to the target value at high temperature. The bandgap voltage distribution of all chips is very concentrated at high temperature, and the value of the bandgap voltage is very scattered at low temperature.

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