Method of foreground auto-calibrating data reception window and related device

Patent metadata

Field	Value
Publication number	US-11270745-B2
Application number	US-201916521577-A
Country	US
Kind code	B2
Filing date	Jul 24, 2019
Priority date	Jul 24, 2019
Publication date	Mar 8, 2022
Grant date	Mar 8, 2022

Abstract

A method of foreground auto-calibrating data reception window for a DRAM system is disclosed. The method comprises receiving data strobe and data from a DRAM of the DARM system, capturing a data strobe clock according to the received data strobe, generating three time points with a period of the data strobe clock, sampling the data at the three time points, to obtain three sampled data, determining whether to adjust positions of the three time points according to a comparison among the three sampled data, and configuring the valid data reception window according to the positions of the three time points when determining not to adjust the positions of the three time points.

First claim

What is claimed is:

1. A method of foreground auto-calibrating data reception window for a dynamic random access memory, DRAM, system the method comprising:
receiving data strobe and data from a DRAM of the DARM system;
capturing a data strobe clock according to the received data strobe;
generating three time points with a period of the data strobe clock;
sampling the data at the three time points, to obtain three sampled data;
determining whether to adjust positions of the three time points according to a comparison among the three sampled data; and
configuring a valid data reception window according to the positions of the three time points when determining not to adjust the positions of the three time points.

2. The method of claim 1 , wherein the step generating the three time points with the period of the data strobe clock comprise:
splitting the period into a previous time point, a center time point and a postpone time point.

3. The method of claim 1 , wherein the step of sampling the data at the three time points, to obtain the three sampled data comprises:
obtaining a previous data corresponding to the previous time point;
obtaining a center data corresponding to the center time point; and
obtaining a third postpone data corresponding to the postpone time point.

4. The method of claim 3 , wherein the step of determining whether to adjust the positions of the three time points according to the comparison among the three sampled data comprises:
determining whether the previous data, the center data and the postponed data are the same;
calculating a first distance between the previous time point and center time point and a second distance between the center time point and the postponed time point;
determining not to adjust the positions of the three time points when determining the previous data, the center data and the postponed data are the same;
shifting the previous time point and postponed time point by one step when the previous data and the postponed data are different from the center data, whereby the previous time point and the postponed time point are adjusted to be close to the center time point;
shifting the center time point by increasing one step when the previous data is different from the center data and the postponed data, and the first distant is smaller or equivalent to the second distance;
shifting the previous time point by increasing one step when the previous data is different from the center data and the postponed data, and the first distant is bigger than the second distance;
shifting the center time point by decreasing one step when the postponed data is different from the center data and the previous data, and the first distant is bigger than the second distance; and
shifting postponed time point by decreasing one step when the postponed data is different from the center data and the previous data, and the first distant is smaller or equivalent to the second distance.

5. The method of claim 4 , wherein the step of configuring the valid data reception window according to the positions of the three time points when determining not to adjust the positions of the three time points comprise:
configuring a range of the valid data reception window with a relative distance between the previous time point and the postponed time point.

6. The method of claim 1 , further comprising:
adjusting the positions of the three time points when determining to adjust the positions of the three time points;
wherein the step of sampling the data at the three time points comprises:
sampling the data at the adjusted three time points, to obtain three sampled data corresponding to the adjusted three time points;

wherein the step of determining whether to adjust the positions of the three time points according to the comparison among the three sampled data comprises:
determining whether to adjust positions of the adjusted three time points according to a first comparison among the three sampled data corresponding to the adjusted three time points.

7. A foreground auto-calibration device for data reception window configuration, the auto-calibration device comprising:
a data strobe clock acquisition unit, for receiving data strobe from a dynamic random access memory (DRAM) and capturing a data strobe clock;
a time point splitting unit, for generating three time points with a period of the data strobe clock;
a data sampling unit, for sampling data from the DRAM at the three time points, to obtain three sampled data; and
a time point adjusting unit, for determining whether to adjust positions of the three time points according to a comparison among the three sampled data, and configuring a valid data reception window according to the positions of the three time points when determining not to adjust the positions of the three time points.

8. The foreground auto-calibration device of claim 7 , wherein the time point splitting unit is further used for splitting the period of the data strobe clock into a previous time point, a center time point and a postponed time point.

9. The foreground auto-calibration device of claim 8 , wherein the data sampling unit is further used for obtaining a previous data corresponding to the previous time point, a center data corresponding to the center time point, and a postponed data corresponding to the postponed time point.

10. The foreground auto-calibration device of claim 9 , wherein the time point adjusting unit is used for determining whether the previous data, the center data and the postponed data are the same, calculating a first distance between the previous time point and center time point and a second distance between the center time point and the postponed time point, determining not to adjust the positions of the three time points when determining the previous data, the center data and the postponed data are the same, shifting the previous time point and postponed time point by one step when the previous data and the postponed data are different from the center data, whereby the previous time point and the postponed time point are adjusted to be close to the center time point, shifting the center time point by increasing one step when the previous data is different from the center data and the postponed data, and the first distant is smaller or equivalent to the second distance, shifting the previous time point by increasing one step when the previous data is different from the center data and the postponed data, and the first distant is bigger than the second distance, shifting the center time point by decreasing one step when the postponed data is different from the center data and the previous data, and the first distant is bigger than the second distance, and shifting postponed time point by decreasing one step when the postponed data is different from the center data and the previous data, and the first distant is smaller or equivalent to the second distance.

11. The foreground auto-calibration device of claim 10 , wherein the time point adjusting unit is further used for configuring a range of the valid data reception window with a relative distance between the previous time point and the postponed time point.

12. A dynamic random access memory, DRAM, system comprising:
a DRAM;
a memory controller, connecting to the DRAM, for performing a read operation with the DRAM; and
a foreground auto-calibration device, connecting to the memory controller and the DARM, for configuring data reception window to the memory controller, wherein the calibration device comprises:
a processing unit, for executing a program code; and
a storage unit, coupled to the processing unit, for storing the program cod

Assignees

• Realtek Semiconductor Corp

Inventors

• Chen Shih-Chang
• Yu Chun-Chi
• Chang Chih-Wei
• Chi Kuo-Wei
• Tsai Fu-Chin
• Lin Shih-Han
• Chou Gerchih

Classifications

• G11C2207/2254

  Calibration · CPC title

• G11C29/028

  with adaption or trimming of parameters · CPC title

• G11C11/4076

  Timing circuits (for regeneration management G11C11/406) · CPC title

• G11C7/222 Primary

  Clock generating, synchronizing or distributing circuits within memory device · CPC title

• G06F1/14

  Time supervision arrangements, e.g. real time clock · CPC title