ZQ calibration controller applied to semiconductor memory

Abstract

The invention provides a ZQ calibration controller applied to a semiconductor memory. The ZQ calibration controller comprises a temperature sensor, a temperature control unit and a ZQ calibration unit, wherein the temperature sensor is used for detecting the temperature of a semiconductor memory; the temperature control unit is used for acquiring and storing a first temperature value and a second temperature value of the semiconductor memory from the temperature sensor, calculating the deviation between the first temperature value and the second temperature value and sending a ZQ calibration starting signal when the deviation exceeds a threshold; and the ZQ calibration unit is used for carrying out ZQ calibration on the semiconductor memory after receiving the ZQ calibration starting signal and sending a ZQ calibration ending signal to the temperature control unit after the ZQ calibration is finished. According to the ZQ calibration controller, by additionally arranging the temperature control unit, the ZQ calibration of the semiconductor memory can be automatically started according to the temperature change of the semiconductor memory, and a resistance value of an output end is improved, so that the integrity of the signal is maintained, the programming burden of the controller is alleviated, the cost is saved, and the power consumption is saved; and an output resistance value of an output port is relatively flexibly and effectively controlled.

Description

technical field [0001] The invention relates to the technical field of semiconductor storage, in particular to a semiconductor storage, a ZQ calibration controller and a ZQ calibration control method thereof. Background technique [0002] For DRAM (Dynamic Random Access Memory, dynamic random access memory), the size and matching of the pull-up (pull-up) / pull-down (pull-down) resistance value of the output terminal affect the integrity of the output signal. In DRAM applications, ZQ calibration (ZQ calibration) is usually used to adjust the output pull-up / pull-down capability (that is, to adjust the pull-up / pull-down resistance value of the output terminal). Such as figure 1 As shown, after the semiconductor memory system is powered on, the controller 10 of the semiconductor memory will send a ZQ calibration command (ZQCL, ZQ Long Calibration, ZQ long type calibration) to the ZQ calibration unit 20, and the ZQ calibration unit 20 performs ZQ calibration to Calibrate the pul...

AI Technical Summary

Problems solved by technology

[0003] As the working state of DRAM in the system changes (such as high-speed frequent read and write and low-speed interval read and write), the chip temperature will change at any time, which will affect the pull-up / pull-down resistance value of the output end, making the pull-up / pull-down resistance of the output end possible. A mismatch will occur again, affecting the integrity of the output signal, requiring the controller 10 to periodically and repeatedly send ZQ calibration commands (ZQCS, ZQ Short Calibration, ZQ short type calibration) to the ZQ calibration unit 20 for ZQ calibration

If the rate of temperature change is not constant, the update of the controller 10 will not be timely, or there will be too many redundant updates, and the power consumption will be too large

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