Digital Home

Freescale Semiconductor

21

MC44CC373

Video Differential Gain

No Audio signal

This is measured using a Demodulator in B/G

(using a CCIR Rec. 567 weighting network,

100 kHz to 5 MHz band with sound trap and

envelope detection, and a Video Analyzer.

On line CCIR 330 shown below, the video analyzer DG measure consists of

calculating the difference of the Chroma amplitude at the black level and the

different amplitudes at each step of the greyscale. The largest positive or

negative difference indicates the distortion.

The video analyzer method takes the worst step from the first 4 steps.

Video Modulation Depth

No Audio signal

Video: 10 step grey scale

This is measured using a Spectrum Analyzer with a TV Trigger option, allowing

demodulation and triggering on any specified TV Line. The analyzer is centred

on the maximum peak of the Video signal and reduced to zero Hertz span in

Linear mode to demodulate the Video carrier.

The Modulation Depth is calculated as (A

− B) / A x 100 in %

Same measurement method for L standard, with inverted video.

Picture to Sound ratio

No Video signal

No Audio Signal

PS bit set to 0 and 1

Measure in dBc sound carrier in reference to picture carrier (RFout_Ref) for PS

bit = 0 (PS = 12 dB typical) and for PS bit = 1 (PS = 16dB).

Table 22. Performance Measurement Test Set-ups (continued)

Device and Signals Set-up

Measurement Set-up

0 123

4 5

5-step greyscale with Chroma, line CCIR330

DIFF GAIN =

* 100%

the amplitude at position 0

the largest positive or negative difference

TV Line Demodulated by Spectrum Analyzer-BG standard

A (mV)

B (mV)

Picture carrier

Sound carrier

+5.5Mhz

Fo