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MC44BC375UAFCR2

MC44BC375UA PLL Tuned VHF Audio/ Video High Integration IC (Channel 3 and 4 80 dBµV RF Level)

Freescale Semiconductor 

Freescale SemiconCdhuarcacttoerriz,atIinoncM.easurement Conditions

Device and Signals Set-up

Measurement Set-up

Audio Modulation Depth - FM Modulation

Video Black Level

Audio signal: 1Khz, 205mVrms.

This is measured using a Rohde &

Schwarz AMFS Demodulator in B/G and

a HP8903A Audio Analyzer at 1kHz

The audio signal 205mV at 1kHz is supplied by the Audio Analyzer, and

the FM demodulated signal deviation is indicated on the Demodulator in

Khz peak.

This value is then converted in% of FM deviation, based on specified

standards.

Audio Frequency response

Video Black Level

Audio signal: 50Hz to 15KHz, 100mVrms

This is measured using a Rohde &

Schwarz AMFS Demodulator in B/G and

a HP8903A.

The audio signal 1KHz 100mVrms is supplied by the Audio Analyzer,

demodulated by the Demodulator and the audio analyzer measures the

AC amplitude of this demodulated audio signal: this value is taken as a

reference (0dB).

The audio signal is then swept from 50Hz to 15KHz, and demodulated

AC amplitude is measured in dB relative to the 1KHz reference.

Audio pre-emphasis and de-emphasis circuits are engaged, all audio

analyzer filters are switched OFF.

Audio Distortion FM

The input rms detector of the Audio Analyzer converts the ac level of the

Audio: 1Khz, adjustable level

combined signal + noise + distortion to dc. It then removes the

Video Black Level

fundamental signal (1kHz) after having measured the frequency. The

This is measured using a Rohde &

output rms detector converts the residual noise + distortion to dc. The dc

Schwarz AMFS UHF Demodulator in B/G voltmeter measures both dc signals and calculates the ratio in% of the

and a HP8903A Audio Analyzer at 1kHz. two signals.

The output level of the Audio analyzer is

varied to obtain a deviation of 50kHz

indicated on the Demodulator.

ADist = (Distorsion + Noise) ⁄ (Distorsion + Noise + Signal)

Audio Signal to Noise

Audio: 1Khz, adjustable level

Video: EBU Color Bars

This is measured using a Rohde &

Schwarz AMFS Demodulator in B/G and

a HP8903A Audio Analyzer at 1kHz. The

output level of the Audio analyzer is

varied to obtain a Modulation Deviation

of 25kHz indicated on the AMFS

Demodulator.

The Audio Analyzer alternately turns ON and OFF it's internal audio

source to make a measure of the Audio signal plus noise and then

another measure of only the noise.

The measurement is made using the internal CCIR468-2 Filter of the

Audio Analyzer together with the internal 30+/-2kHz (60dB/decade)

Lowpass filters.

The AMFS demodulator uses a quasi-parallel demodulation as is the

case in a normal TV set. In this mode the Nyquist filter is bypassed and

the video carrier is used without added delay to effectuate intercarrier

conversion. In this mode the phase noise information fully cancels out

and the true S/N can be measured

ASN(dB) = 20 × log(Signal + Noise) ⁄ (Noise)

MC44BC375UA Advance Information

For More Information On This Product,

Go to: www.freescale.com

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