The MSM7652 is a digital NTSC/PAL encoder. By inputting digital image data conforming to
ITU Rec. 656 or ITURBT 601, it outputs selected analog composite video signals, analog S video
signals or Y, R-Y, B-Y signals. For the scanning system, interlaced or noninterlaced mode can be
selected.
Since the MSM7652 is provided with pins dedicated to overlay function, text and graphics can
be superimposed on a video signal.
In addition, this encoder has an internal 10-bit DAC. So, when compared with using a conventional
analog encoder, the number of components, the board space, and points of adjustment can
greatly be reduced, thereby realizing a low cost and high-accuracy system.
The MSM7652 provides the optional functions such as Closed Caption Signal Generation
Function.
The host interface provided conforms to Philips's I2C specifications, which reduces
interconnections between this encoder and mounting components.
The internal synchronization signal generator (SSG) allows the MSM7652 to operate in master
mode.
9IOLROverlay text color (Red component)
10IOLGOverlay text color (Green component)
11IOLBOverlay text color (Blue component)
12OCLKX1O13.5 MHz divided clock output signal
13IOUTSEL
14DV
DD
15DGNDDigital GND
16I/OVSYNC_L
17I/OHSYNC_L
18IBLANK_L
19, 20IYD7 to YD6
21NCNot connected
22 to 27IYD5 to YD0
28DGNDDigital GND
29DV
DD
30ICLKX2Clock input pin (27 MHz)
31 to 38I/OCD7 to CD0
39ICLKSEL
3.3 V digital power supply
Selects between Master and Slave at 27 MHz or 13.5 MHz YCbCr operation. Pulled down
Transparent control signal. "1" indicates overlay signal. Normally fixed to "0".
. Normally fixed to "0".
. Normally fixed to "0".
. Normally fixed to "0".
Video output signal format select pin. "0" : Y/C & Composite signal,
"1" : Y/B-Y/R-Y (component) signal. Pulled down
3.3 V digital power supply
Vertical sync signal input/output pin (ITU656: O, YCbCr: I/O)
Negative polarity
Horizontal signal input/output pin (ITU656 : O, YCbCr: I/O)
Negative polarity
Composite blank signal. Negative polarity. See the description on page 15
for the operating requirement.
MSB 2 bits of 8-bit digital image data input pins (for ITU656 and
YCbCr 27 MHz). Level conforms to ITU-601.
MSB 2 bits of 8-bit digital image luminance signal input pins (for YCbCr).
Level conforms to ITU-601.
YD7 is MSB.
LSB 6 bits of 8-bit digital image data input pins (for ITU656 and
YCbCr 27 MHz). Level conforms to ITU-601.
LSB 6 bits of 8-bit digital image luminance signal input pins (for YCbCr).
Level conforms to ITU-601.
YD0 is LSB.
3.3 V digital power supply
8bit digital image chrominance signal data input pins (13.5 MHz mode).
Level conforms to ITU-601. Fixed to "0" for ITU Rec. 656, 27 MHz-YCbCr mode.
Operation mode select pin. "0" : 27 MHz mode / "1" : 13.5 MHz mode.
5
MSM7652¡ Semiconductor
PIN DESCRIPTIONS (2/2)
PinI/OSymbolDescription
40ISEL1
Enable pin. Normally fixed to "0". Sleep mode "1" with TEST1 = "0"
(See Page 32 for details)
41ISEL2
42DV
DD
Pulled down
3.3 V digital power supply
43DGNDDigital GND
Interface select pin. ITU656 : "0", YCbCr 27 MHz : "1" (See Page 32 for details)
44ITEST1
45ITENB
Input pin1 for testing. Normally fixed to "0". (See Page 32 for details)
Pulled down
Input pin2 for testing.
Normally fixed to "0"
.
Pulled down
46I/OVREFReference voltage for DAC
47IFSDAC full scale adjustment pin.
48ICOMPDAC phase complement pin.
49AGNDAnalog GND
50OCA
51AV
DD
52OCVBSO
Analog color chrominance signal output pin or component B-Y signal
output pin.
3.3 V analog power supply
Analog composite signal output pin or component R-Y signal output pin.
53AGNDAnalog GND
54OYAAnalog luminance signal output pin or component Y signal output pin.
55AV
DD
3.3 V analog power supply
56DGNDDigital GND
6
¡ SemiconductorMSM7652
ABSOLUTE MAXIMUM RATINGS
Parameter
Power Supply Voltage
Input Voltage
Analog Output Current
Power Consumption
Storage Temperature
Symbol
DV
DD
AV
DD
V
I
I
O
P
W
T
STG
Condition
—
—
= 3.3 V
DV
DD
—
—
—
RECOMMENDED OPERATING CONDITIONS
Parameter
Power Supply Voltage (*1)
"H" Level Input Voltage
"L" Level Input Voltage
Operating Temperature 1Ta1
Operating Temperature 2Ta2
Symbol
DV
DD
AV
DD
V
IH
V
IL
Condition
—
—
—
—
DVDD = AVDD = 3.3 V
DVDD = AVDD = 3.3 V
DA output load = 37.5 W
Min.
3.0
3.0
2.2
—
0
Rating
Unit
–0.3 to +4.5
V
–0.3 to +4.5
–0.3 to +5.5
50
600
–55 to +150
Typ.
3.3
Max.
3.6
V
mA
mW
°C
Unit
V
3.3
—
—
25˚C
3.6
—
0.8
70
V
V
25˚C065
DVDD = AVDD = 3.3 V,
External Reference VoltageVrefex
Ta = 25˚C
1.25V——
DA Current Setting Resistance Riadj(*2)385W——
DA Output Load ResistanceR
L
(*3)75W——
(*1)Supply an equal voltage to both DVDD and AVDD.
(*2)A volume control resistor of approx. 500 W is recommendable for adjusting the output
current. When a DA converter analog output is terminated with a 37.5 W load, Riadj
= approx. 192 W.
(*3)Indicates the value when Riadj = 385 W (typical value).
7
MSM7652¡ Semiconductor
ELECTRICAL CHARACTERISTICS
DC Characteristics
(Ta = 0 to 70°C, DV
ParameterSymbol
"H" Level Output VoltageV
"L" Level Output VoltageV
Input Leak CurrentI
Output Leak CurrentI
Power Supply Current (operating)I
—mA3—
Internal Reference VoltageVrefin—1.25V——
DA Output Load ResistanceR
L
—75W
Integral LinearitySINL—±2LSB
Differential LinearitySDNL—±1LSB
(*1)VSYNC_L, HSYNC_L, CD[7:0]
(*2)CLKX1O
(*3)SDA
AC Characteristics
ParameterSymbolConditionMin.Typ.Max.Unit
CLKX2 Cycle TimeT
Input Data Setup Time
Input Data Hold Time
Output Delay Time
CLKX1O Delay Time
2
C-bus Clock Cycle Timet
I
2
C-bus High Level Cyclet
I
2
C-bus Low Level Cyclet
I
S
t
s1
t
h1
t
d1
t
d2
C_SCL
H_SCL
L_SCL
(Ta = 0 to 70°C, DV
—
—
—
—
—
Rpull_up = 4.7 kW
= 3.3 V ±0.3 V, AVDD = 3.3 V ±0.3 V)
DD
——
36.4ns
7ns
5ns
525ns
525ns
200
100—
100
—
—
—
—
——
—ns
——
—
—
nsRpull_up = 4.7 kW
nsRpull_up = 4.7 kW
8
¡ SemiconductorMSM7652
INPUT/OUTPUT TIMING
Input timing
TS
CLKX2
ts1
td1
Invalid data
th1
valid data
HSYNC_L,
VSYNC_L, BLANK_L,
YD, CD, MS, MODE,
OLR, OLG, OLB, OLC
Output timing
HSYNC_L, VSYNC_L
CLKX1O
td2
I2C-bus Interface Input/Output Timing
The following figure shows I2C-bus basic input/output timing.
SDA
SCL
S
Start Condition
Data Line Stable: Data Valid
MSB
12789
Change of Data Allowed
ACK
t
C_SCL
I2C-bus Basic Input/Output Timing
12
t
L_SCL
t
H_SCL
3-8
9
ACK
P
Stop Condition
9
MSM7652¡ Semiconductor
BLOCK FUNCTIONAL DESCRIPTION
1. Prologue Block
This block separates input data at the ITU Rec.656 format into a luminance signal (Y) and a
chrominance signal (Cb & Cr), and also generates information concerning sync signals
HSYNC_L, VSYNC_L, and BLANK_L.
This block separates input data at the 27 MHz YCbCr (8-bit input) format into a luminance
signal (Y) and a chrominance signal (Cb & Cr).
This block separates input data at the 13.5 MHz YCbCr (16-bit input) format into a chrominance
signal Cb and a chrominance signal Cr.
Of the processed input data, luminance and chrominance signals other than valid pixel data
are replaced by 8'h10 and 8'h80 respectively.
2. Y Limiter Block
This block limits the luminance input signal by clipping the lower limit of an input signal outside
the ITU601 Standard
• Signals are limited to YD = 16 when YD < 16.
• Signals are limited to TD = 254 when YD (input during a valid pixel period) = 255.
In other cases, signals are fed as is to next processing.
3. C Limiter Block
This block limits the chrominance signal by clipping the upper and lower limits of the input
signal outside the ITU601 Standard.
CD = 1 when CD = 0 is input during a valid pixel period.
CD = 254 when CD = 255 is input during a valid pixel period.
• Y Level Converter
Converts ITU-601 standard luminance signal level to DAC digital input level.
• U Level Converter
Converts ITU-601 standard chrominance signal level to DAC digital input level.
• V Level Converter
Converts ITU-601 standard chrominance signal level to DAC digital input level.
• YUV Color Generator
This block generates luminance and chrominance signals from over lay color signals OLR,
OLG and OLB. Control signals (CR [2:0] ) control the output content (overlay or color bar) and
output level (100%, 75%, 50%, 25%).
• Overlay Control
This block selects input image data or YUV Color Generator output signals.
It is determined by the level of the control signal (OLC, CR [2]), as shown below: (x : don't care)
CR [2] = 1, OLC = x: Selects color bar signal (YUV Color Generator output signal).
CR [2] = 0, OLC = 1: Selects overlay signal (YUV Color Generator output signal).
CR [2] = 0, OLC = 0: Selects input image data.
10
¡ SemiconductorMSM7652
• Black & Blank Pedestal
This block adds sync signals at the luminance side to luminance signals.
• Interpolator + LPF
This block executes data interpolation and the elimination of high frequency components by
LPF for input chrominance signals.
•I2C Control Logic
This is the serial interface block based on I2C standard of Phillips Corporation.
Internal registers MR and CR can be set from the master side.
When writing to the internal registers other than MR [1] (black level control) and CR [1:0]
(overlay level), written contents are immediately set to them. It is during the vertical blanking
period that written contents are set to MR [1] and CR [1:0].
• Sync Generator & Timing Controller
This block generates sync signals and control signals.
This block operates in slave mode, which performs external synchronization, and in master
mode, which internally generates sync signals.
• Color Burst Generator
Outputs U and V components of amplitude of burst signals.
• Subcarrier Generator
Executes color subcarrier generation.
• Interpolation Filter (IPF)
This block performs upsampling at CLKX2 for luminance signals and chrominance signals
modulated with CLKX1 divided from CLKX2. Interpolation processing is executed in this
process.
• Closed Caption Block
This block generates the signal for closed caption.
11
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