Voltage-to-time converter and method for reducing parasitic capacitance and power supply influences

Patent metadata

Field	Value
Publication number	US-11115039-B2
Application number	US-201917057702-A
Country	US
Kind code	B2
Filing date	May 13, 2019
Priority date	May 23, 2018
Publication date	Sep 7, 2021
Grant date	Sep 7, 2021

Abstract

The present disclosure provides a voltage-to-time converter and method for reducing parasitic capacitance and power supply influences. The voltage-to-time converter includes: a main sampling network, a compensation sampling network, a discharge network and an over-threshold detection unit. The influence of a traditional VTC parasitic capacitance on a VTC output swing amplitude is reduced by using the compensation sampling network. A sampling common-mode level of the compensation sampling network is compensated, such that the influence of the low-frequency disturbance of a power supply voltage on a threshold of a traditional VTC threshold detection circuit is reduced. The output swing amplitude of the voltage-to-time converter of the present disclosure can reduce the influence of a parasitic capacitance. A voltage common-mode level of a VTC input end is related to a power supply voltage, which reduces a conversion error caused by the influence of the power supply voltage on a threshold.

First claim

The invention claimed is:

1. A voltage-to-time converter for reducing influences of parasitic capacitance and power supply, comprising:
a main sampling network, to sample a main input signal and a main reference level;
a compensation sampling network, to sample a compensation input signal and a compensation reference level;
the main sampling network comprises a main sampling capacitor and a main sampling common-mode level, the main sampling common-mode level samples and converts a difference between an input voltage and a reference voltage; the compensation sampling network comprises a compensation sampling capacitor and a compensation sampling common-mode level, the compensation sampling common-mode level samples and converts the difference between the input voltage and a reference level, and compensates the input voltage;
a discharge network, to discharge the main sampling capacitor and the compensation sampling capacitor;
an over-threshold detection unit, to detect whether the output level of the discharge network exceeds the threshold and convert an input level into time.

2. The voltage-to-time converter for reducing influences of parasitic capacitance and power supply according to claim 1 , wherein in a sampling stage, the main sampling network and the compensation sampling network simultaneously sample the input voltage; in a conversion stage, the compensation sampling network is connected to the main sampling network, and performs voltage-time domain conversion simultaneously with the main sampling network.

3. The voltage-to-time converter for reducing influences of parasitic capacitance and power supply according to claim 2 , wherein in the conversion phase, a relationship between a voltage of an input end of the over-threshold detection unit and the input voltage is:

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V TCD is the voltage of the input end of the over-threshold detection unit, V CMSP is a main sampling common-mode level, V IN is the input voltage, V REF is a reference voltage, V CC is a compensation sampling common-mode level, C S is a main sampling capacitance, C C is a compensation sampling capacitance, CP is a parasitic capacitance at the input end of the over-threshold detection unit.

4. A voltage-to-time converter for reducing influences of parasitic capacitance and power supply according to claim 3 , wherein a relationship between the compensation sampling common-mode level V CC and a power supply voltage V DD , and a relationship between a voltage threshold V TH of the over-threshold detection unit and the power supply voltage V DD are:

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Assignees

• No 24 Research Institute Of China Electronics Tech Group Corporation

Inventors

• Li Ting
• Huang Zhengbo
• Zhang Yong
• Ni Yabo
• Wang Jian'An
• Fu Dongbing

Classifications

• H03M1/54 Primary

  Input signal sampled and held with linear return to datum · CPC title

• G01R19/16538 Primary

  in AC or DC supplies (G01R19/16519 and G01R19/16528 take precedence) · CPC title

• H03M1/129

  Means for adapting the input signal to the range the converter can handle, e.g. limiting, pre-scaling (H03M1/18 takes precedence); Out-of-range indication · CPC title

• H03M1/1245 Primary

  Details of sampling arrangements or methods · CPC title