Socket Signal Integrity Assessment for High Speed LPDDR4 Memory Test Applications

Abstract

As the data rate of Low Power Double Data Rate 4 (LPDDR4) memory is reaching higher speeds, it is becoming more crucial to evaluate and assess the electrical performance of the viable socket technologies in the market. This paper presents a signal integrity (SI) evaluation for gripper-type pin technology, one of the commercially available socket technologies which potentially can be enabled for high speed LPDDR4 memory test applications with a data transmission rate of up to 2.4 Gb/s. We performed three-dimensional numerical simulations with a commercially available 3D FEM (finite element method)-based full-wave software package (Ansoft HFSS). We evaluated No-Socket vs. Single-Sided gripper socket pins and compared their signal transmission characteristics. Simulation results showed that the worst case margin degradation for the single-sided gripper socket could be improved by reducing the Z-axis height of the socket pin to minimize crosstalk and achieve better performance at higher GHz frequencies.