32k crystal oscillator based on high signal-to-noise ratio pulse injection

Abstract

A 32k crystal oscillator based on high signal-to-noise ratio pulse injection adopts a T / 4 clock delay shaping circuit with high phase noise performance, high frequency precision and ultra-low power consumption and a pulse generation circuit to realize a crystal oscillator with a pulse injection structure with a high signal-to-noise ratio. A T / 4 clock delay shaping circuit designed on the basis ofa delay circuit structure is used for accurately positioning wave crests and wave troughs; a pulse generation circuit designed based on the structure of a frequency divider and a bootstrap circuit isused for generating pulses, voltage superposition is carried out on the basis of power supply voltage by utilizing the principle of the bootstrap circuit, so that pulse signals are amplified, high-energy signals are generated, and on the premise that the frequency precision and stability are guaranteed, the contradictory relationship between the power consumption and stability of the crystal oscillator and the phase noise performance is solved.

Description

technical field [0001] The invention relates to a 32k crystal oscillator based on high signal-to-noise ratio pulse injection, belonging to the technical field of integrated circuits. Background technique [0002] 32k crystal oscillators are widely used in integrated circuits, as a real-time clock signal generation module, providing real-time clock signals for systems on chips (System on Chip, SoC) such as measuring equipment and sensors. The 32k crystal oscillator based on high signal-to-noise ratio pulse injection uses pulse injection to provide energy for the crystal oscillator. Compared with traditional crystal oscillators (Crystal Oscillator, XO), high signal-to-noise ratio pulse injection optimizes the circuit phase noise performance and reduces Disturbances from supply voltage and temperature variations and therefore have better noise immunity characteristics. The noise performance of the 32k crystal oscillator affects the frequency accuracy of the real-time clock, an...

AI Technical Summary

Problems solved by technology

The noise performance of the 32k crystal oscillator has an impact on the frequency accuracy of the real-time clock, which in turn affects the performance of the entire system where the 32k crystal oscillator is located

However, this method needs to add a capacitor network module, which will generate a lot of extra power consumption, increase the structural complexity, and greatly increase the chip area and cost, and the practicability is greatly reduced.

At the same time, the capacitor network and multi-voltage domain work introduce electrical noise, which affects circuit noise performance, anti-PVT performance and frequency accuracy

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