|
|
PDF MC44302A Data sheet ( Hoja de datos )
| Número de pieza | MC44302A | |
| Descripción | ADVANCED MULTI-STANDARD VIDEO/SOUND IF | |
| Fabricantes | Motorola Semiconductors | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de MC44302A (archivo pdf) en la parte inferior de esta página. Total 28 Páginas | ||
|
No Preview Available !
Order this document by MC44302A/D
MC44302A
Advanced Information
Advanced Multi-Standard TV
Video/Sound IF
The MC44302A is a multi–standard single channel TV Video/Sound IF
and PLL detector system specifically designed for use with all standard
modulation techniques including NTSC, PAL, and SECAM. This device
enables the designer to produce a high quality IF system with a minimum
number of external components.
The MC44302A contains a high gain video IF with an AGC range of 80 dB,
enhanced phase–locked loop carrier regenerator for low static phase error,
doubly balanced full wave synchronous video demodulator featuring wide
bandwidth positive and negative video outputs with extremely low differential
gain and phase distortion, video AFT amplifier, multistage sound IF limiter
with FM quadrature detector and AFT for self tuning, AM sound detector,
constant and variable audio outputs, dc volume control for reduced hum and
noise pickup, unique signal acquisition circuit that prevents false PLL lockup
and AFT push out, horizontal gating system with sync separator and
phase–locked loop circuitry for self–contained RF/IF AGC operation, RF
AGC delay circuitry, and programmable control logic that allows operation in
NTSC, and PAL SECAM systems. This device is available in wide body 28 pin
dual–in–line and surface mount plastic packages.
• Multi–Standard Detector System for NTSC, PAL, and SECAM
• High Gain Video IF Amplifier with 80 dB AGC Range
• Enhanced PLL Carrier Regenerator for Low Static Phase Error
• Synchronous Video Demodulator with Positive and Negative Video
Outputs
• Sound IF with Self Tuning FM Quadrature Detector
• AM Sound Detector
• DC Volume Control
• Unique Signal Acquisition Circuit Prevents False PLL Lockup
• Horizontal Gating System for Self Contained RF/IF AGC Operation
• RF AGC Delay Circuitry
Simplified Television Block Diagram
VHF/UHF
Tuner
SAW
Filter
Luma & Chroma
Processor
Video
Drivers
Vertical & Horizontal
Scan Circuitry
ADVANCED
MULTI–STANDARD
VIDEO/SOUND IF
SEMICONDUCTOR
TECHNICAL DATA
28
1
28
1
P SUFFIX
PLASTIC PACKAGE
CASE 710
DW SUFFIX
PLASTIC PACKAGE
CASE 751F
(SO–28L)
PIN CONNECTIONS
DC Volume Control 1
Sound Input (FM) 2
Audio Input/
Audio–Video Switch
Sound
De–Emphasis (FM)
Negative Video Out
3
4
5
Positive Video Out 6
Sound AFT Filter/ 7
Peak White Filter
Video IF Input 8
Video IF Input 9
Video Mode Switch 10
AFT Output 11
AFT Mode Switch 12
RF AGC Output 13
Video IF AGC Filter 14
28
Intercarrier
Sound Output
27
Audio Output
(Variable)
26 Sound Quadrature
Coil (FM)
25 VCC
24
Audio Output
(Constant)
23 Sound Input (AM)
22 Gnd
21 VCO Coil
20 VCO Coil
19
PLL Filter
(Main VCO Loop)
18 Lock Detector/Filter
(Acquisition Circuit)
17 Flyback/Video Input
16 Horizontal PLL Filter
15 RF AGC Delay
Video
IF
Video
Detector
Sound
IF
Sound
Detector
(Top View)
RF/IF
AGC
MC44302A
AFT
Horizontal
Gating System
DC Volume
Control
Mode
Switch
Audio
Amp
Power
Supply
ORDERING INFORMATION
Device
Tested Operating
Temperature Range Package
MC44302ADW
TA = 0° to +70°C
MC44302AP
SO–28L
Plastic DIP
This document contains information on a new product. Specifications and information herein
arMe OsuTbjOecRt tOo cLhAangAeNwAithLoOut GnotIiCce.DEVICE DATA
© Motorola, Inc. 1997
Rev 0
1
1 page  
MC44302A
Figure 1. IF AGC Filter Voltage versus
Carrier Differential Input Voltage
2.5
VCC = 5.0 V
fC = 45.75 MHz
2.0 RF AGC Delay, Pin 15, Open
TA = 25°C
1.5
Input
1.0 Overload
Region
0.5
Figure 2. Carrier Differential Input Voltage versus
RF AGC Takeover Threshold
1000
VCC = 5.0 V
fC = 45.75 MHz
100 TA = 25°C
10
1.0
0
0.01 0.1 1.0 10 100 1000
CARRIER DIFFERENTIAL INPUT VOLTAGE (mVrms)
0.1
1.4
1.6 1.8 2.0 2.2
RF AGC TAKEOVER THRESHOLD, PIN 15 (V)
2.4
Figure 3. VCO Characteristics
1000
Hold–In Range
100
Figure 4. VCO Free–Running and Offset
Frequency Change versus Supply Voltage
100
fVCO = 22.875 MHz
C19, C20 = 33 pF
∆foffset
50 TA = 25°C
100
50
Sweep Capture Range
10
0
∆fVCO
0
Lock–In Range
1.0 VCC = 5.0 V
fVCO = 22.875 MHz
0.1
C19, C20 = 33 pF
TA = 25°C
–50
–100
0.01 –150
41 42 43 44 45 46 47 48
4.5
CARRIER FREQUENCY (MHz)
–50
–100
Readings are taken at five minute intervals
allowing the die temperature to stabilize.
–150
4.7 4.9 5.1 5.3 5.5
VCC, SUPPLY VOLTAGE (V)
Figure 5. PLL Filter Voltage versus
Carrier Frequency Change
4.8
VCC = 5.0 V
fVCO = 22.875 MHz
C19, C20 = 33 pF
4.0 TA = 25°C
3.2
2.4
1.6
–2.0
–1.0 0
1.0
CARRIER FREQUENCY CHANGE (MHz)
2.0
1.0
0
–1.0
–2.0
2.0 –2.0
Figure 6. AFT Output Current
versus Carrier Frequency Change
Pin 12 = Gnd
VCC = 5.0 V
fVCO = 22.875 MHz
C19, C20 = 33 pF
Pin 11 = 2.5 V
TA = 25°C
Pin 12 = VCC
–1.0 0
1.0
CARRIER FREQUENCY CHANGE (MHz)
2.0
MOTOROLA ANALOG IC DEVICE DATA
5
5 Page 
MC44302A
Video and Sound Intercarrier Demodulation
To ensure that the above performance improvements
were not lost elsewhere, great care was taken with the
design of the video demodulator and video amplifiers. One
example is in the architectural placement of the phase shift
amplifier (Figure 22) that is required for video demodulation.
This amplifier was placed in series with the IF signal side of
the demodulator, instead of the oscillator side as is common
practice. The 90° phase shift is obtained by a capacitively
coupling each of the differential amplifier driver emitters to
the video demodulator inputs. This results in an output
current that is at 90° with respect to the input voltage over a
wide range of frequencies. Small phase errors that are
caused by the transistor dynamic small–signal emitter
resistance are corrected with the use of cross–coupled
emitter resistors. This arrangement leads to a simpler design
with the ability to tailor the demodulation angle for the lowest
possible distortion at the IF/demodulator interface. The
dynamic emitter resistances, which can give rise to distortion,
are now in quadrature with the capacitive reactance and
therefore contribute very little to the resultant output.
After the PLL attains phase–lock, video and sound
demodulation is obtained by the use of two separate double
balanced multipliers. Video demodulation is accomplished by
multiplying the non–limited 90° phase shifted carrier signal,
with the regenerated vision carrier that is obtained from the
Frequency Doubler output. Both positive and negative video
outputs are produced. The phase relationship between the
video demodulator inputs is 0° since the carrier signal is
phase shifted 90°. This is done in order to cancel out the 90°
phase shift that is present at the inputs of the Phase Detector
when it is locked. The sound intercarrier signal is also
recovered by a multiplier in a similar manner to that of the
video. In this case the carrier signal is not phase shifted, and
the phase relationship between the sound demodulator
inputs is 90°. A consequence of this phase relationship is that
only the higher frequency video components are
demodulated while the lower frequency components, those
that fall within the vestigial sideband, are suppressed. With
negative polarity modulation systems, a significant reduction
in the level of white character sound buzz and hum is
achieved. This is most noticeable when demodulating video
signals that contain a high luma level which can cause the
modulation index to exceed 100 percent.
Figure 22. 90° Phase Shift Amplifier
+ Iout
Iout +
Vref
+Vin –Vin
Video Outputs
Each of the video outputs are part of a wide bandwidth
operational amplifier with internal dc feedback and frequency
compensation. The AGC reference provides the same
composite video output level of approximately 2.2 Vpp for
both positive and negative polarities of video modulation. The
positive video output appears at Pin 6 and is intended to drive
the luma and chroma channels. This output contains a White
Spot Inverter that is used to invert and clamp any
demodulated noise that is significantly above the white level.
This effectively removes the whiter than white noise
produced by the true synchronous demodulator and prevents
the CRT from being overdriven and defocused. The white
spot inversion threshold and clamp levels are set to
approximately 4.0 V and 2.5 V respectively. The negative
video output appears at Pin 5 and is intended to be used as
a sync separator source. With a simple preseparator low
pass noise filter, this output will provide optimum sync
performance. The video outputs are designed to drive a
resistive load that is in the range of 2.0 kΩ. Lower resistance
values could increase differential phase and gain distortion.
Figure 23. Positive Video Output with
White Spot Inversion
White Spot Inversion Threshold
4.0 V
3.7 V
Normal
2.5 V
0% and
100%
Carrier
Levels
1.2 V
White Spot Clamp Level
AM & FM Sound IF and Detection
The intercarrier sound that is present at Pin 28 normally
connects through a ceramic bandpass filter to either the FM
IF and Detector input at Pin 2, or the AM IF and Detector
input at Pin 23. With the FM IF, intercarrier sound is limited by
a five stage ac coupled amplifier yielding high sensitivity and
a high level of AM rejection. The typical limiting threshold is
80 µV, and the AM rejection ratio is in excess of 50 dB. FM
detection is accomplished by a self tuning quadrature
demodulator. An internal reactance stage with phase
compensation is controlled to automatically adjust the tuning
of an external tank circuit eliminating the need for manual
alignment. The tank is a parallel circuit consisting of a fixed
value inductor, capacitor, and resistor. The tuning range is
controlled by the ratio of the internal capacitance change to
that of the fixed external tank capacitance. The internal
capacitance is controlled by the voltage present on the
Sound AFT Filter, Pin 7. The capacitance ranges from
0.25 pF to 19 pF, refer to Figure 9. Figure 10 shows the self
tuning frequency range for three inductor values. In general,
for fixed frequency applications, the external tank
capacitance should be in the range of 56 pF to 82 pF. This
should allow sufficient tuning range to account for the
component tolerances. The L–C values should be selected
so that the AFT filter operates below 2.4 V when properly
tuned to the sound intercarrier. This yields the best low signal
lock–in performance, since the AFT filter voltage approaches
1.0 V under no signal conditions. Multi–standard applications
that require a wide intercarrier tuning range can be
accomplished by using a small external capacitance with a
MOTOROLA ANALOG IC DEVICE DATA
11
11 Page | ||
| Páginas | Total 28 Páginas | |
| PDF Descargar | [ Datasheet MC44302A.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| MC44302A | ADVANCED MULTI-STANDARD VIDEO/SOUND IF | Motorola Semiconductors |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |