Reference current source with temperature compensation function

Abstract

The invention discloses a reference current source with a temperature compensation function, and relates to the field of integrated circuit design. The reference current source with the temperature compensation function comprises a temperature coefficient adjusting circuit, a bias circuit, a current mirroring circuit and an output circuit; the temperature coefficient adjusting circuit is used foradjusting the temperature coefficient of the reference current source; the bias circuit is used for providing the bias voltage for the temperature coefficient adjusting circuit; the current mirroringcircuit is used for mirroring the adjusted reference current source to the output circuit; the output circuit is used for outputting the adjusted reference current source to a load; and the temperature coefficient adjusting circuit comprises a first field-effect tube, a second field-effect tube and a third field-effect tube which are connected in sequence and adjusts the temperature coefficient ofthe reference current source by presetting the channel width-to-length ratios of the first field-effect tube, the second field-effect tube and the third field-effect tube correspondingly. The temperature compensation of current reference is achieved through the simple circuits, and the layout area is decreased.

Description

Technical field [0001] The invention relates to the field of integrated circuit design, in particular to a reference current source with temperature compensation. Background technique [0002] The reference current source is widely used in analog integrated circuits, and its output current provides reference current and drive current for other modules. In practical applications, the current reference source is usually required to be independent of the power supply voltage. In some applications, the current reference source is also required to meet the characteristics of low temperature coefficient, low voltage operation, and low power consumption. Therefore, designing a reference current source with a low temperature coefficient and independent of voltage has become the key to circuit applications. [0003] Due to technological limitations, traditional voltage-independent reference sources generally use poly resistors with a negative temperature coefficient. At this time, the refe...

AI Technical Summary

Problems solved by technology

[0003] Due to process limitations, traditional voltage-independent reference sources generally use poly resistors with negative temperature coefficients. At this time, the reference current has positive temperature coefficients, which cannot meet the requirements of low temperature coefficient reference current sources.

At the same time, when a small current (nA level) is required in the circuit, it generally requires a larger layout area and more types of devices to obtain the required reference current, which increases the cost of the circuit.

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