摘要:
The invention relates a method of extracting synchronization signals from an input video signal (Csync) comprising horizontal synchronization pulses at the start of video lines, for generating a horizontal synchronization signal (Hsync), said method comprising:—a calculation step (105) for calculating the duration (D) of the video lines in said input video signal (Csync),—a forcing step (108) for forcing said input video signal (Csync) to an output level, said output level corresponding to the level of said input video signal (Csync) after the horizontal synchronization pulses, said input signal (Csync) being forced between the end of each horizontal synchronization pulse and a moment defined by a first percentage (X1) of said line duration (D), for generating said horizontal synchronization signal (Hsync). Use: Extraction of synchronization signals.
摘要:
The invention relates a method of extracting synchronization signals from an input video signal (Csync) comprising horizontal synchronization pulses at the start of video lines, for generating a horizontal synchronization signal (Hsync), said method comprising:—a calculation step (105) for calculating the duration (D) of the video lines in said input video signal (Csync),—a forcing step (108) for forcing said input video signal (Csync) to an output level, said output level corresponding to the level of said input video signal (Csync) after the horizontal synchronization pulses, said input signal (Csync) being forced between the end of each horizontal synchronization pulse and a moment defined by a first percentage (X1) of said line duration (D), for generating said horizontal synchronization signal (Hsync). Use: Extraction of synchronization signals.
摘要:
The invention relates to an A/D conversion device having an amplifier (A) which receives an analog input signal (Vin), in which device the voltage level of reference thresholds in the output signal (Vout�0:7!) resulting from the A/D conversion of the input signal (Vin) is maintained constant by means of a regulation module (CMP1, IS), controlling the voltage which is present at the terminals of a storage capacitor (Cs). According to the invention, such a device controls the average DC component of the input signal (Vin) in the purpose of limiting the amplitude of the variations of said signal (Vin), which variations might lead to a saturation of the amplifier (A).
摘要:
The invention relates to an A/D conversion device intended to supply at the output a digital signal Vout[0:7] resulting from the conversion of an analog input voltage Vin and receiving a control signal CRS used for defining the transfer characteristic of the device by way of comparison with the output signal Vout[0:7]. According to the invention, such a device comprises a reference module (AO, CMP2) which allows adjustment of the digital value of the output signal Vout[0:7] at a predetermined value when the analog input voltage Vin is zero, and means (Mx, Vact) for substituting for said voltage Vin a reference voltage Vref having a predetermined value when the device is in its control mode.
摘要:
A conversion device includes an A/D converter (8) and a control module for auto-adjustment of the DC component. This module includes an analog comparator (5) which performs a comparison between the analog signal (11) at the input of the A/D converter (8) and a reference voltage (10) produced on the basis of voltages which feed the resistance ladder (9) of the converter. In order that the control does not introduce noise into the signal supplied, the comparator (5) of the control module has a non-linear response with a reduced output/input gain for a range of the differential control signal centered around zero.