Operational-amplifier-free high-order low-temperature-drift bandgap reference circuit

Abstract

The invention discloses an operational-amplifier-free high-order low-temperature-drift bandgap reference circuit. The reference circuit comprises a starting circuit, a bias circuit, a positive temperature coefficient circuit, a negative temperature coefficient circuit, a positive temperature coefficient compensation circuit and a negative temperature coefficient compensation circuit. The operational-amplifier-free high-order low-temperature-drift bandgap reference circuit adopts an operational-amplifier-free circuit structure, and the power supply rejection ratio (PSRR) of an output referencevoltage is increased by a BJT current mirror. The circuit provided by the invention has the characteristics of wide voltage input of 12 to 36V, width-adjustable output voltage of 0 to 7V, generation of a reference voltage of 5ppm / DEG C in the temperature range of 75 to 125 DEG C, extremely low power consumption of 35mW and high-order temperature compensation.

Description

technical field [0001] The invention belongs to the field of integrated circuits and relates to a bandgap reference circuit without high-order low-temperature drift of operational amplifiers. Background technique [0002] As a high-precision ADC, DAC converter and a basic component in communication circuits, the bandgap reference circuit provides an accurate voltage source or current source for other circuit modules. With the rapid development of system integration technology, the reference voltage source has become an indispensable basic circuit module in large-scale, VLSI and almost all digital and analog systems. Its temperature characteristics and anti-noise ability are key factors affecting the accuracy and performance of integrated circuits. The traditional bandgap reference circuit produces a reference voltage with a temperature coefficient of about 50ppm / °C in the temperature range of 0-70°C. In high-precision ADCs, DAC converters, and circuit modules with high-per...

AI Technical Summary

Problems solved by technology

In order to obtain a high-performance bandgap reference voltage in a traditional circuit, a high-performance operational amplifier is required to stabilize the voltage in the circuit design, which not only increases the difficulty of the design, but also increases the complexity of the circuit design, and the structure of the operational amplifier occupies a large chip area. Increase the design cost, which seriously restricts the development needs of integrated circuit miniaturization; at the same time, the minimum operating voltage of the operational amplifier limits the minimum input voltage of the bandgap reference circuit

In the prior art, the bandgap reference voltage source circuit basically uses a circuit with an operational amplifier structure to stabilize the voltage. The input voltage range is as low as 3.3V to 5V, and the temperature coefficient is about 10ppm, which limits the application of the bandgap reference voltage source circuit to high precision. , miniaturized ADC, DAC converter and circuit modules with high performance requirements

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