摘要 |
A clock signal generator for a USB device. The clock signal generator includes a control circuit and a clock generator that does not need to include a crystal oscillator. The control circuit counts the cycle of the clock signal during the period between two sync signals successively inputted, and generates a frequency control signal corresponding to the count value. The clock generator generates the clock signal with a frequency corresponding to the frequency control signal. The clock signal generator can generate a clock signal that is suitable for the data transfer rate defined, in the USB specification. In addition, the clock; signal generator can generate an RX clock signal so that an RX data signal can be recovered with its energy being stable.
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