Launch of ST51 Series Connector Compatible with microSD™ EXPRESS Cards

July 16, 2025

JAE has developed and begun selling the ST51 Series push-push type connector compatible with the new microSD EXPRESS card standard, a recording medium capable of high-speed reading and writing of large volumes of data.

Overview

In recent years, with the advancement of ICT devices and the increase in electronic data volume, demand is expected to grow for microSD EXPRESS cards, which offer faster data transfer speeds compared to the conventional microSD cards with UHS-I/UHS-II standards, for video recording and external storage applications.
In response to this trend, JAE has developed and started selling the “ST51 Series”, a push-push type connector compatible with microSD EXPRESS cards. This new product inherits the proven mechanical lock mechanism (*1) and multi-point hold-down structure (*2) from JAE’s previous models, ensuring secure card lock performance and robustness, while adding dedicated high-speed transmission terminals to enable high-capacity, high-speed data communication compliant with the microSD EXPRESS standard.
Furthermore, EMC and heat dissipation measures have been incorporated into the hold-down structure, allowing the product to address challenges associated with high-speed transmission while maintaining a board footprint comparable to existing products. In addition to microSD EXPRESS cards, it also supports UHS-I and UHS-II standard cards (*3), making it suitable for a wide range of applications.

• Mechanical lock mechanism: A mechanism that provides a mechanical lock using “stopper” and “lock” components. It offers strong resistance to vibration and physical shocks.
• Multi-point hold down structure: A reinforcement fitting for board mounting that provides robustness, electromagnetic compatibility measures, and heat-dissipating effects.
• The communication speed when mating a UHS-II card will be limited to UHS-I.

microSD Card Comparison

	UHS-Ⅰ	UHS-Ⅱ	EXPRESS
Pin Layout
Compatible Connectors	ST12 Series and Others	ST50 Series	ST51 Series

Mechanical Lock Mechanism

Multi-Point Hold-Down Structure

Features

• Push-push type connector for microSD EXPRESS cards standardized by SDA (*4)
• Supports PCIe® 3.0 x 1
• Dimensions: 1.4 mm (H) x 14.6 mm (W) x 15.95 mm (D); 17.37 mm including card, and maintains a footprint comparable to the existing product
• Push stroke: 0.7 mm, card eject distance: 3.18 mm, ensures ease of operation
• Card detection switch included (D-SW): normally open type
• Multi-point hold-down structure provides robustness, EMC performance, and heat dissipation
• Mechanical locking structure for secure card retention

＊4：SDA SD Association (a standards body that sets standards for SD memory cards)

Applicable Markets

General Specifications

Materials and finishes

• microSD™ is a trademark of the SD Association.
• PCIe is a trademark of PCI-SIG.

ST51 Series(For more details)

Information and details given here are as of the date of publication. Please note that the details may be changed.