A High Precision Low Temperature Drift Bandgap Reference Voltage Source

Abstract

The invention discloses a high-accuracy low-temperature-drift bandgap reference voltage source. The bandgap reference voltage source comprises a positive temperature coefficient current generation circuit which generates a current in direct proportion to an absolute temperature, a negative temperature coefficient current generation circuit which generates a current in inverse proportion to the absolute temperature, a two-time temperature detection and compensation circuit which enables a bandgap reference to obtain three or more temperature inflection points within an operating temperature range by conducting addition compensation on the positive temperature coefficient current and the negative temperature coefficient current, a starting circuit which drives the positive temperature coefficient current generation circuit and the negative temperature coefficient current generation circuit to get rid of degeneracy bias points to establish normal working points in the electrified process of a power supply and a current summing circuit which generates bandgap reference voltage. According to the bandgap reference voltage source, two temperature control current comparators are introduced to achieve multi-time temperature compensation, five temperature inflection points are obtained within the full temperature range, and an additional biasing circuit is not needed; an operational amplifier is not needed for voltage clamping, and the circuit complexity is reduced.

Description

technical field [0001] The invention belongs to the field of integrated circuit design, in particular to a high-precision bandgap reference voltage source circuit. Background technique [0002] Many high-precision circuits, such as analog-to-digital and digital-to-analog converters, phase-locked loops, and power management systems, require low-temperature drift bandgap reference sources as reference voltages. Traditional bandgap voltage circuits usually use first-order temperature compensation, that is, linear compensation for the BE junction temperature coefficient, to obtain a temperature inflection point; or second-order curvature temperature compensation, that is, to increase the square term of the temperature coefficient in BE on the basis of the first-order compensation. Compensation, the temperature inflection point is 2 to 3; but the temperature drift of the bandgap reference after compensation is greatly affected by the processing technology, and the temperature ran...

AI Technical Summary

Problems solved by technology

Traditional bandgap voltage circuits usually use first-order temperature compensation, that is, linear compensation for the BE junction temperature coefficient, to obtain a temperature inflection point; or second-order curvature temperature compensation, that is, to increase the square term of the temperature coefficient in BE on the basis of the first-order compensation. Compensation, the temperature inflection point is 2 to 3; but the temperature drift of the bandgap reference after compensation is greatly affected by the processing technology, and the temperature range is narrow, it is difficult to meet some fields that have wide requirements for the application temperature range; some based on such as Bandgap reference source circuits of bipolar and thin film resistor technologies can achieve a temperature drift of several ppm, but they are not compatible with standard CMOS processes and cannot be fully integrated on-chip

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