A Stub Equalizer for Bidirectional and Single-Ended Channels in NAND Memory Storage Device Systems


In memory devices, such as solid-state drive, multitopology is used for interfaces where multiple memory packages are connected to a controller using a branched transmission line. Impedance mismatching caused by the branches and unwanted reflection from deactivated packages inevitably degrades signal quality, limiting the data rate of the interface. In this article, a simple stub equalizer is proposed to improve the data rate of the memory interface. An open-ended stub is placed between a transmitter and a receiver, and the length, impedance, and location of the stub line are determined to properly cancel the reflection from other branches. Parameters are optimized based on the peak distortion analysis and an exhaustive search considering both read and write modes. The improvements are validated through eye-diagram simulations.


Electrical and Computer Engineering

Research Center/Lab(s)

Electromagnetic Compatibility (EMC) Laboratory


This work was supported by National Science Foundation under Grant IIP-1916535.

Keywords and Phrases

Equalizer; Peak Distortion Analysis (PDA); Signal Integrity (SI); Solid-State Drive (SSD); Stub Equalizer

International Standard Serial Number (ISSN)

1558-187X; 0018-9375

Document Type

Article - Journal

Document Version


File Type





© 2022 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Feb 2022