Reference current source for semiconductor integrated circuit

Abstract

Embodiments relate to a reference current source for a semiconductor integrated circuit. The reference current source comprises a voltage source, an operational amplifier, a feedback transistor, a switched-capacitor circuit and a non-overlapping clock control module, wherein the voltage source is configured to provide a reference voltage between a first power supply terminal and a second power supply terminal; an in-phase input end of the operational amplifier is coupled to the second power supply terminal; a gate electrode of the feedback transistor is coupled to an output end of the operational amplifier, a source electrode of the feedback transistor is coupled to an inverting input end of the operational amplifier, and a drain electrode is used for providing a reference current; the switched-capacitor circuit comprises a first capacitor, a first switch and a second switch, the first capacitor and the second switch are connected in series between the first power supply terminal and the inverting input end of the operational amplifier, and the first switch is connected with the first capacitor in parallel; and the non-overlapping clock control module is configured to generate a first clock signal for controlling the first switch and a second clock signal for controlling the second switch based on a crystal oscillator clock signal, and the first clock signal and the second clock signal are not overlapped, so that the first switch and the second switch are alternately conducted.

Description

technical field [0001] Embodiments of the present disclosure generally relate to the field of semiconductor integrated circuits, and more particularly, to a reference current source for a semiconductor integrated circuit and a semiconductor integrated circuit including the reference current source. Background technique [0002] Reference current sources play a very important role in analog signal processing systems and mixed signal processing systems, and are used to provide current references for other circuits in the system. For example, reference current sources are widely used in many semiconductor integrated circuits such as analog-to-digital converters (ADC), digital-to-analog converters (DAC), sensors, etc., and their accuracy and stability will directly affect the signal processing accuracy of these circuits, such as ADC Or the conversion accuracy of DAC, etc., the sensing signal accuracy of sensors, etc. How to design an accurate and stable reference current source...

AI Technical Summary

Problems solved by technology

However, due to the need to compensate not only the first-order temperature coefficient, but also the second-order temperature coefficient, it is difficult to compensate for temperature drift

In addition, due to the process discrete fluctuation of the temperature drift of the resistor and its resistance value, it is necessary to use an additional circuit to perform independent trimming and compensation for each resistor sample, resulting in complex circuit design and high later trimming costs.

Images