Selection and Specification of Crystals for Texas Instruments USB 2Application Report SLLA122 - December 2002 Selection and Specification of Crystals for Texas Instruments USB 2.0 Devices Julie McElligatt Connectivity Solutions Peripheral Applications ABSTRACT Every USB high-speed application must support a data rate of 480 Mb/s within ±500 ppm (479.760 Mb/s to 480.240 Mb/s) to comply with the Universal Serial Bus Specification Revision 2.0. For Texas Instruments USB 2.0 devices, it is recommended that the clocks of the USB 2.0 devices be derived from an external crystal. Evaluation of the properties of the crystal will ensure that the selected crystal will function as expected in the system. Capacitor selection and layout can also affect the operation of the crystal. This application note details the preferred crystal properties, as well as guidelines f……