2024年5月4日发(作者：)

USB Engineering Change Notice

USB ENGINEERING CHANGE NOTICE

Title: Clarification on the Chamfer on USB 2.0 Micro Connectors

Applies to: MicroUSB Specification to the USB 2.0 Specification,

Revision 1.01

Summary of ECN

Modify the USB2.0 micro receptacle definition so that the external chamfer metals are optional as they

are in the USB3.0 micro specification.

Reasons for ECN

A number of the portable device manufacturers are asking for Micro-series receptacles that have the

lead-in chamfer removed. This is primarily an Industrial Design concern as it improves the aesthetics of

products.

Impact on Existing Peripherals and Systems:

No significant impact on the existing parts as they still conform to the specification. Even if the chamfer

metals are removed, the guiding function and the insertion force stay the same because the inner side of

the shell edge has taper.

Hardware Implications:

None.

Software Implications:

None.

Compliance Testing Implications:

The change does not affect the mechanical and electrical performance specified in the current USB2.0

compliance specification. The test items in the specification were all passed.

USB ECN: USB 2.0 Phase-Locked SOFs

1

USB Engineering Change Notice

Specification Changes

Universal Serial Bus Micro-USB Cables and Connectors specification Revision 1.01

The ECR proposes to add a note “Chamfer metals are optional with no sharp edges.” to the Figure 4-9

Micro-AB receptacle interface on the page 24 and to the Figure 4-10 Micro-B receptacle interface on the

page 25 as shown in the following pages.

USB ECN: USB 2.0 Phase-Locked SOFs

2