VBS mode detection device of digital television

摘要

The present invention relates to a VSB mode detection apparatus in a US-oriented digital TV receiver using a residual sideband (VSB) method, and particularly, the last 8 symbols of a VSB mode signal interval (= 24 symbols) of a field sync signal inserted at every 313 data segment positions. By extracting only the most significant bit having code information from a certain bit of digital data while detecting the VSB mode inserted at the transmitting side, the hardware is simplified, which makes integration easier and IC size smaller, resulting in lower cost. do. In addition, if the extracted code bits are serially outputted, they are sequentially converted to 8-bit parallel data by sequentially delaying them for a predetermined clock and the combination of the parallel data is determined to determine whether there is an error in the input data. When an error is detected, the operation of all circuits used for VSB mode detection is stopped and the VSB mode signal section of the next vertical synchronization signal is waited. When an error occurs in the input data, the VSB mode detection is stopped. Can be detected.