Low power consumption oscillator circuit with selectable frequency

Abstract

The invention discloses a low power consumption oscillator circuit with selectable frequency. The low power consumption oscillator circuit comprises a frequency selection unit (1), a bias current unit(2) and an oscillation unit (3); wherein the frequency selection unit (1) generates a frequency selection signal F-sel and inputs the same to the bias current unit (2), the bias current unit (2) provides charging current I1, I2 for the oscillation unit (3), and the oscillation unit (3) generates an OSC clock signal under the action of I1, I2. The low power consumption oscillator circuit has the advantages of having a simple circuit structure, eliminating a comparator and a control part in the traditional OSC, and having a small chip area and low power consumption; the frequency selection unitcan change and select the OSC frequency, so that the oscillation unit switches different modes, thereby being flexible and variable; and the current sources I1, I2 mirror current via a cascade current mirror, so that the stability of the generated current is high, the stability of the OSC oscillation frequency is realized, and the process drift is significantly inhibited.

Description

technical field [0001] The invention belongs to electronic circuit technology, in particular to a low-power oscillator circuit, which can be used in DC-DC converters. Background technique [0002] Oscillator circuits are used as a frequency source in a wide variety of electronic circuits, and have great market potential in the field of electronic communications. There are four main types of oscillators: ring oscillators, LC oscillators, crystal oscillators, and relaxation oscillators. The circuit of the ring oscillator is simple, and it is easy to start the oscillation, but it is not convenient to choose the network frequency without delay, and it occupies a large area. LC oscillators are rarely used because inductors are not easy to integrate in circuits. The crystal oscillator has high precision and low temperature coefficient, and the output performance is optimal, but its cost is high and power consumption is high, and it is not widely used in the electronic field. Th...

AI Technical Summary

Problems solved by technology

The design of this traditional structure comparator is relatively complicated, the circuit consumes a lot of power, occupies a large area, and the current source is also formed by an external bias, resulting in low current accuracy and insufficient output stability of the comparator. In addition, the traditional The output frequency of the oscillator is single and cannot be selected and changed

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