TDA5670-5X Datasheet, PDF (16/22 Pages) Siemens Semiconductor Group – Video Modulator for FM/AM-Audio with PLL-Output

TDA 5670-5X
Test Circuit 6
Description of the Measurement Configuration to Measure the Modulation Depth
for Positive and Negative Modulation
Calibration:
Measuring:
A zero reference signal with the TV-measuring receiver is given to the video signal.
A video signal with V_vid = 1 Vpp is connected to the video input.
1) Modulation depth m_D/N for negative modulation: pin 14 open, range peak white
value – sync level in relation to range zero reference – sync level gives m_D/N.
2) Modulation depth m_D/P for positive modulation: pin 14 to ground, range peak
white value – sync level in relation to range zero reference – peak white value gives
m_D/P.
Semiconductor Group
16