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18

Freescale Semiconductor

MC44CC373

CHARACTERIZATION MEASUREMENT CONDITIONS

The default configuration unless otherwise specified:

•

Peak White Clip enabled

•

UHF oscillator ON

•

Sound and video modulators ON

•

Sound subcarrier frequency = 5.5 MHz

•

Sound Oscillator ON

•

Sound PLL reference frequency = 31.25 kHz

•

Logic Output Port LOW

•

Picture-to-sound carrier ratio = 12 dB

•

System L disabled

•

Test pattern disabled

•

All test mode bits are ‘0’

•

Frequency from channel 21 to 69

•

RF Inputs / Output into 75

Ω Load using a 75 to 50 Ω

transformation.

•

Video Input 1Vpp.

•

Audio pre-emphasis circuit enabled.

Table 22. Performance Measurement Test Set-ups

Device and Signals Set-up

Measurement Set-up

Video: 10 steps grey scale

No audio

Measured picture carrier in dB

μV with a Spectrum Analyzer using a 75 to 50 Ω

transformation, all cables losses and transformation pads having been

calibrated.

Measurement used as a reference for other tests: RFout_Ref

ATT bit = 1

No Video signal

No Audio signal

Measure in dBc picture carrier at ATT=1 with reference to picture carrier at

ATT=0

Sound Subcarrier Harmonics

Video: 10 steps grey scale

No Audio signal

Measure in dBc second and third sound harmonics levels in reference to

picture carrier (RFout_Ref).

Second Harmonics of Chroma Subcarrier

No audio

signal is inserted on the black level of active

video area.

Measure in dBc, in reference to picture carrier (RFout_Ref), second harmonic

of chroma at channel frequency plus 2 times chroma frequency, resulting in the

following spectrum.

Picture carrier

Sound carrier

Sound

+5.5MHz

Fo

+11MHz +16.5MHz

2nd harm

Sound

3rd harm

Frequency

4.43 MHz

Picture carrier

Sound

Chroma 2nd

+8.86MHz

Fo

+4.43MHz +5.5MHz

Harmonic

carrier

Chroma

carrier