TDA5666-5 Datasheet, PDF (15/22 Pages) Siemens Semiconductor Group – Video Modulator for FM-Audio

TDA 5666-5
Test Circuit 5
Description of the Measurement Configuration to Measure the Video and/or Noise
in Audio
Calibration:
Measuring:
AF-signal of f = 1 kHz, corresponding with a nominal deviation of 30 kHz, is
connected to the audio input, and the demodulated AF-reference level at the audio
measurement device is defined as 0 dB. No video signal is present.
1) The AF-signal is switched off and the FuBK-video signal is connected to the video
input with V_vid = 1 Vpp. The audio level in relation to the AF-reference calibration
level is measured as ratio a_V/A.
2) AF- and video signal are switched off. The noise ratio in relation to the AF-
reference calibration level is measured as signal-to-noise ratio in the audio signal
a_N/A.
Semiconductor Group
15