Synchronization device for transmitting real-time voice data by USB

• Main Authors: LIN CHUNAN, WU MINXING
• Format: Patent
• Language: Chinese; English
• Published: 02.05.2012
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; TELEPHONIC COMMUNICATION; TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHICCOMMUNICATION

The invention discloses a synchronization device for transmitting real-time voice data by a USB, which comprises a first addition unit, a frame start count-down unit, a phase locking circuit, a frequency dividing unit, a second addition unit, a third addition unit, a fourth addition unit, a frame calibration and scratch memory unit, a fifth addition unit, a calibration and mapping unit and a calibration pulse generation unit. Therefore, a frame start identifier transmitted by a USB host computer is used as a reference cycle in 1ms, and a high-frequency clock pulse generates a first clock pulse signal through the frequency dividing unit; the pulse number of the first clock pulse signal in a USB start frame is fixed, but the absolute time can be automatically fine-tuned with the time lengthof the previous frame start; and therefore, the synchronization device can solve the problem of desynchronized data transmission between the USB host computer and an external device.