mc44144 Freescale Semiconductor, Inc, mc44144 Datasheet - Page 4

• Manufacturer Part Number: mc44144
• Description: Subcarrier Phase-locked Loop
• Manufacturer: Freescale Semiconductor, Inc

Subcarrier
Output
Ground
Phase
Detector
Output
4X Sub Xtal
4X Subcarrier
Output (or
Black Burst)
Composite
Video Input
(Black Burst,
Continuous
Wave, or
Composite
Chroma
can also be
applied)
Burst Gate
Input
V CC
4
Name
Pin
1
2
3
4
5
6
7
8
400
Representative Circuitry
gm
5.0k
5.0k
V CC
V CC
V CC
V CC
V ref
200
22k
22k
1.0k
33k
22k
gm
2.0k
PIN FUNCTION DESCRIPTION
2.5V
31k
V CC
MC44144
Subcarrier Output. A
phase–locked reference of the
PAL or NTSC color burst is
output at this pin.
Circuit Ground
The error current from the
phase detector is output at this
pin. A filter circuit should be
connected at this pin.
Crystal Oscillator Pin. A 4X
subcarrier parallel resonant
crystal, in series with a 5.0 to
25 pF trimmer capacitor
provides the resonant element
for the Voltage Controlled
Crystal Oscillator (VCXO).
Buffered output from the 4X
voltage controlled oscillator.
Composite Video Input. Color
burst from the video present at
this pin is used as a reference
to phase lock the VCXO.
Positive or negative video may
be used.
Input for the phase detector
gate pulse. TTL compatible.
The threshold is nominally
2.6V.
Power Supply Pin. 5.0 Vdc
should be applied at this pin.
Description
MOTOROLA ANALOG IC DEVICE DATA
A 300 mVpp square wave is output.
Some high frequency content is
present.
A beat waveform, showing both
horizontal period and half the
subcarrier period, is present.
Approximately 40 mVpp. A scope
probe will disturb the frequency of
oscillation.
The sinusoidal 4Xf sc oscillator output
is available at this pin.
The output is nominally:
Composite video should be applied
at this pin. The color burst
amplitude of the input video should
be at least 50 mV, but no more than
1000 mV. The waveform at this pin
should not exceed ground or V CC .
A positive going gate pulse should
be applied at this pin. The Burst Gate
input should envelope the color
burst.
Pin 6
Pin 7
525 mVpp for NTSC,
425 mVpp for PAL.
Expected Waveforms
1/2 Subcarrier Period
Line Period
V CC
2.6V
GND
2.2V
V lock