zq calibration control applied to semiconductor memory

Abstract

The invention provides a ZQ calibration controller of a semiconductor memory, comprising: a temperature sensor for detecting the temperature of the semiconductor memory; a temperature control unit for obtaining and storing the first temperature value and the second temperature value of the semiconductor memory from the temperature sensor Temperature value, calculating the deviation between the first temperature value and the second temperature value, sending a signal to start ZQ calibration when the deviation exceeds the threshold; ZQ calibration unit, used to perform ZQ calibration on the semiconductor memory when receiving the signal to start ZQ calibration , and send the ZQ calibration end signal to the temperature control unit at the end of ZQ calibration. In the present invention, by adding a temperature control unit, the semiconductor memory can automatically start ZQ calibration according to its own temperature change, thereby improving the resistance value of the output end to maintain the integrity of the signal, and also reducing the programming burden of the controller, saving cost and power consumption; The control of the output resistance of the output port is more flexible and effective.

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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