CMOS subthreshold reference circuit with low power consumption and low temperature drift

Abstract

The invention discloses a CMOS subthreshold reference circuit with low power consumption and low temperature drift and belongs to the technical field of power management. The CMOS subthreshold reference circuit comprises a start-up circuit, a negative temperature coefficient voltage generator circuit and a positive temperature coefficient voltage generator circuit. The start-up circuit enables the grid end of a first NMOS transistor to be pulled up at the initial stage of the reference circuit so that the circuit is out of the zero state and begins to work normally, and after that, the start-up circuit quits. The negative temperature coefficient voltage generator circuit extracts the threshold voltage VTHN of the NMOS transistor and takes the threshold voltage VYHN as the negative temperature coefficient voltage. The positive temperature coefficient voltage generator circuit utilizes the MOS transistor having equal drain source and different width-to-length ratio and working at the subthreshold region to generate positive temperature coefficient voltage. The positive temperature coefficient voltage and the negative temperature coefficient voltage output from the negative temperature coefficient voltage generator circuit are superposed to output reference voltage VREF. The reference circuit has the characteristic of approximating zero temperature within a certain temperature range and can realize ultra-low power consumption at mu W order.

Description

technical field [0001] The invention belongs to the technical field of power management, and in particular relates to the design of a sub-threshold MOSFET-based ultra-low power consumption and low-temperature drift reference generation circuit. Background technique [0002] The reference voltage source is an extremely important part of analog integrated circuits and digital-analog hybrid circuits, and is widely used in power converters, power amplifiers, digital-to-analog converters and other circuits. The function of the reference voltage source is to provide a voltage reference independent of temperature and power supply voltage for the circuit. As the power supply voltage continues to drop, it is critical to design a reference source with low voltage, low power consumption, and low temperature coefficient. Mobile electronic devices have higher and higher requirements on power consumption, so that the power supply voltage of the reference voltage source should be able to ...

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Problems solved by technology

[0003] However, traditional bandgap reference sources are difficult to meet the requirements of low-power reference sources due to the limitation of BE junction voltage; non-bandgap reference sources often use the gate-source voltage VGS of sub-threshold MOSFET as the negative temperature value, and the high-order nonlinear Linear temperature term results in poor reference performance

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