90% Increase in USB-C® Cables Testing Throughput

Organization

• A leading high-speed digital cables product manufacturer

Challenges

• Increasing USB-C device test ports required multiport testing

• Increasing test times from manual setup and port re-connection

• The need to reduce test costs to meet operating profitability

Solutions

• Keysight S94USBCB automated interconnects compliance test solution  to test USB-C cables with 20-ports switch matrix system

Results

• Achieved ~90% total test time reduction of USB-C (USB4 Gen3) cable from 5 hours to ~30 minutes

Introduction

USB Type-C is a breakthrough standard designed to meet the demand for technologies that support higher data rates and lower power in consumer electronics, IT, computing and peripherals. USB standards are maintained by the USB Implementers Forum (USB-IF) and widely adopted in most of the latest electronic devices and equipment. To achieve compliance to the standard, users need to perform a comprehensive range of transmitter, receiver, repeater and cable tests in accordance with the compliance test specification (CTS).

Challenges

The new USB Type-C cables and connectors CTS revision 2.1 released by USB-IF has extended more complex compliance test requirements to support a wide variety of cable types and USB generations.  EG. Test-Group B8 high speed signal test for USB4 Gen3 to support 40 Gbps (20 Gbps/lane). It created several challenges for design and test engineers while they are conducting the test validation to ensure interoperability and compliance of their products.

1.     Increasing number of device test ports 

The increase of USB Type-C port count is driving the demands for an expanded test system. USB  Type-C, DisplayPort (DP) and Thunderbolt connectors require a 20-port VNA system to avoid tedious cable port re-connections during the test. USB4 Gen3 high-speed signal testing requires 44 port connections using a 4-ports VNA. A true multiport PXI-VNA could be a good choice but also incurs a higher test cost.

2.     Manual setup and lengthy test time

The conventional way of testing USB Type-C cables is manual following the test procedures in the Method of Implementation (MOI) document provided by Keysight.  Without software automation available to automate the compliance tests, calibration, measurement  setup, and test execution are prone to unnecessary human errors making compliance tests inefficient  and challenging.

3.     Compliance test tools

USB-IF introduced new test requirements for USB4 Gen3 cables with Channel Operating Margin (COM) and integrated crosstalk analysis that required a Matlab-based compliance test tool (Get_iPar.exe) to compile the 44-sets of S-parameters for compliance verdict judgement. Users need to manually setup the tool’s configuration file to compile and verify pass/fail verdict. Other cable types on USB4 Gen2 and USB 3.2 Gen2, USB 3.2 Gen1 also required similar Matlab test tool (IntePar.exe) for compliance result compilation. The number of USB Type-C test port counts and multiple manual test steps resulted in approximately 3 to 5 hours of testing time for one USB4 Gen3 cable.