SONY CXA1645P

CXA1645P/M
RGB Encoder
For the availability of this product, please contact the sales office.
Description
The CXA1645P/M is an encoder IC that converts
analog RGB signals to a composite video signal. This
IC has various pulse generators necessary for
encoding. Composite video outputs and Y/C outputs for
the S terminal are obtained just by inputting composite
sync, subcarrier and analog RGB signals.
It is best suited to image processing of personal
computers and video games.
24 pin SOP (Plastic)
24 pin DIP (Plastic)
Features
• Single 5V power supply
• Compatible with both NTSC and PAL systems
• Built-in 75Ω drivers
(RGB output, composite video output, Y output, C
output)
• Both sine wave and pulse can be input as a
subcarrier.
• Built-in band pass filter for the C signal and delay
line for the Y signal
• Built-in R-Y and B-Y modulator circuits
• Built-in PAL alternate circuit
• Burst flag generator circuit
• Half H killer circuit
Structure
Bipolar silicon monolithic IC
Absolute Maximum Ratings
14
V
• Supply voltage
VCC
• Operating temperature Topr
–20 to +75
°C
• Storage temperature Tstg –65 to +150
°C
• Allowable power
PD CXA1645P 1250 mW
dissipation
CXA1645M 780 mW
Recommended Operating Condition
Supply voltage
VCC1, 2 5.0 ± 0.25
V
Applications
Image processing of video games and personal
computers
Block Diagram and Pin Configuration
GND2
ROUT
GOUT
BOUT
CVOUT
VCC2
FO
YTRAP
YOUT
COUT
VREF
IREF
24
23
22
21
20
19
18
17
16
15
14
13
75
DRIVER
75
DRIVER
VIDEO
OUT
R-OUT
G-OUT
Y/C
MIX
B-OUT
REGULATOR
DELAY
SYNC
ADD
MATRIX
CLAMP
BPF
R-Y
Modulator
B-Y
Modulator
CLAMP
CLAMP
SIN-PULSE
CLAMP
PHASE
SHIFTER
PULSE
GEN
1
2
3
4
5
6
7
8
9
10
11
12
GND1
RIN
GIN
BIN
NC
SCIN
NPIN
BFOUT
YCLPC
SYNCIN
NC
VCC1
Sony reserves the right to change products and specifications without prior notice. This information does not convey any license by
any implication or otherwise under any patents or other right. Application circuits shown, if any, are typical examples illustrating the
operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits.
–1–
E93411A41-ST
CXA1645P/M
∗ Externally applied voltage
Pin Description
Pin
No.
1
Symbol
GND1
Pin voltage
Equivalent circuit
Description
Ground for all circuits other than RGB,
composite video and Y/C output circuits.
The leads to GND2 should be as short and
wide as possible.
0V∗
VCC1
2
3
4
100µ
Black level
when
clamped
2.0V
180µ
RIN
GIN
BIN
100µ
2
3
4
Analog RGB signal inputs. Input
100%, = 1Vp-p (max.). To minimize clamp
error, input at as low impedance as
possible.
ICLP turns ON only in the burst flag period.
GND1
ICLP
5
NC
NO CONNECTION
VCC1
6
SCIN
—
Subcarrier input.
Input 0.4 to 0.5Vp-p sine wave or pulse.
20P 20k
6
129
Refer to Notes on Operation, Nos. 3 and 5.
20k
100µ
2.5V
GND1
VCC1
80k
68k
7
NPIN
1.7V
Pin for switching between NTSC and PAL
modes
NTSC: VCC, PAL: GND
7
3k
32k
GND1
VCC1
8
BFOUT
H : 3.6V
L : 3.2V
BF pulse monitoring output. Incapable of
driving a 75Ω load.
8
129
25µ
25µ
GND1
–2–
CXA1645P/M
Pin
No.
Symbol
Pin voltage
Equivalent circuit
Description
VCC1
129
9
YCLPC
2.5V
Pin to determine the Y signal clamp time
constant.
Connect to GND via a 0.1µF capacitor.
9
1.6V
5µ
GND1
VCC1
40k
10
SYNC
IN
2.2V
Composite sync signal input. Input TTLlevel voltages.
L ( ≤ 0.8V): SYNC period
H ( ≥ 2.0V)
10
4k
2.2V
GND1
12
VCC1
Power supply for all circuits other than RGB,
composite video and Y/C output circuits.
Refer to Notes on Operation. Nos. 4 and 10.
5.0V∗
VCC1
13
IREF
Pin to determine the internal reference
current.
Connect to GND via a 47kΩ resistor.
2.0V
13
129
50µ
GND1
VCC1
14
VREF
4.0V
Internal reference voltage.
Connect a decoupling capacitor of
approximately 10µF.
14
Refer to Notes on Operation, Nos. 4 and 7.
GND1
–3–
CXA1645P/M
Pin
No.
Symbol
Pin voltage
Equivalent circuit
Description
VCC2
VCC1
600µ
15
COUT
2.2V
Chroma signal output. Capable of driving a
75Ω load.
15
10k
20k
Refer to Notes on Operation, Nos. 6 and 9.
GND2
VCC2
VCC1
600µ
16
YOUT
Black level
1.3V
Y signal output. Capable of driving a 75Ω
load.
16
10k
20k
Refer to Notes on Operation, Nos. 6 and 9.
GND2
VCC1
17
YTRAP
Black level
1.6V
8.5k
17
1.5k
0.5P
GND1
Input resistance 1.5kΩ
Pin for reducing cross color caused by the
subcarrier frequency component of the Y
signal. When the CVOUT pin is in use,
connect a capacitor or a capacitor and an
inductor in series between YTRAP and
GND. Decide capacitance and inductance,
giving consideration to cross color and the
required resolution.
No influence on the YOUT pin.
Refer to Notes on Operation, No. 8.
VCC1
18
FO
Internal filter fo adjustment pin.
Connect to GND via the following resistor
according to the NTSC or PAL mode.
NTSC: 20kΩ (±1%)
PAL : 16kΩ (±1%)
2.0V
18
129
50µ
GND1
–4–
CXA1645P/M
Pin
No.
19
Symbol
VCC2
Equivalent circuit
Pin voltage
Description
Power supply for RGB, composite video and
Y/C output circuits. Decouple this pin with a
large capacitor of 10µF or above as a high
current flows.
5.0V∗
Refer to Notes on Operation, Nos. 4 and 10.
VCC2
VCC1
600µ
CVOUT
Composite video signal output. Capable of
driving a 75Ω load.
20
20k
10k
20
Black level
1.2V
Refer to Notes on Operation, Nos. 6 and 9.
GND2
500µ
21
22
23
BOUT
GOUT
ROUT
Black level
1.7V
VCC2
VCC1
Analog RGB signal outputs. Capable of
driving a 75Ω load.
21
22
23
5.5k
Refer to Notes on Operation, Nos. 6 and 9.
200µ
GND1
GND2
24
GND2
Ground for RGB, composite video and Y/C
output circuits. The leads to GND1 should
be as short and wide as possible.
0V∗
–5–
CXA1645P/M
Electrical Characteristics
(Ta = 25°C, VCC = 5V, See the Electrical Characteristics Measurement Circuit.)
S1
Item
Current
consumption 1
Symbol
S2
S3
S4
S5
Measu
RIN
rement
SYNC
GIN SCIN NPIN
FO point
IN
BIN
ICC1
ICC1
2V SG4 5V SG5 20k
Current
consumption 2
ICC2
ICC2
Measurement
Conditions
Min.
No input signal,
SG5: CSYNC
TTL level,
SG4: SIN wave
3.58MHz
0.5Vp-p
Fig. 1
Typ.
Max.
Unit
31
mA
12
(R, G, BOUT)
RGB output
voltage
RGB output
frequency
characteristics
D
VO (R)
SG1
VO (G)
SG2
VO (B)
SG3
F
fC (R)
SG1
D
fC (G)
SG2
fC (B)
SG3
E
2V
2V
E
F
SG1 to SG3:
DC direct
coupling 2.5VDC,
1.0Vp-p
f = 200kHz
Pin 9 = Clamp
voltage
Fig. 2
0.64
SG1 to SG3:
DC direct
coupling 2.5VDC,
1.0Vp-p
f = 200kHz/5MHz
Pin 9 = Clamp
voltage
Fig. 3
–3.0
0.71
0.78
Vp-p
dB
(YOUT & CVOUT)
Output sync level
VO (YS1/2)
R100%: Y level
VO (YR1/2)
B100%: Y level
SG1
0V
VO (YG1/2) to
SG3
VO (YB1/2)
White 100%: Y level
VO (YW1/2)
G100%: Y level
Output frequency
characteristics
fC (Y1/2)
5V SG5 20k
B/C
SG1
to
0V
SG3
5V
2V
20k
SG1 to SG3:
100% color bar
input,
1.0Vp-p (Max.)
SG5: CSYNC
TTL level
Fig. 4
SG1 to SG3:
DC direct
coupling 2.5VDC,
1.0Vp-p
f = 200kHz/5MHz
Pin 9 = Clamp voltage
Fig. 3
∗ Clamp voltage: voltage appearing at Pin 9 when CSYNC is input.
–6–
0.26
0.29
0.33
Vp-p
0.17
0.21
0.26
V
0.35
0.42
0.49
V
0.065
0.08
0.095
V
0.6
0.71
0.82
V
–3.0
dB
CXA1645P/M
S1
Item
Symbol
S2
S3
S4
S5
Measu
RIN
rement
SYNC
GIN SCIN NPIN
FO point
IN
BIN
Measurement
Conditions
Min.
Typ.
Max.
Unit
0.2
0.25
0.3
Vp-p
2.84
3.16
3.48
94
104
114
2.65
2.95
3.25
231
241
251
2.01
2.24
2.47
337
347
357
deg
2.5
2.75
3.2
µs
0.4
0.6
0.75
µs
20
mVp-p
(COUT & CVOUT)
Burst level
R chroma ratio
R phase
G chroma ratio
G phase
B chroma ratio
B phase
VO (BN1/2)
R/BN1/2
SG1 to SG3:
100% color bar
input,
1.0Vp-p (Max.)
SG4: SIN wave,
3.58MHz
0.5Vp-p
SG5: CSYNC
TTL level
Fig. 5
θR1/2
G/BN1/2
θG1/2
B/BN1/2
SG1
to SG4
SG3
5V SG5 20k
θB1/2
Burst width
tW (B) 1/2
Burst position
tD (B) 1/2
A/C
Carrier leak
PAL burst
level ratio
VL1/2
SG1
to SG4
SG3
5V SG5 20k
K (BP1/2)
θPAL1/2
PAL burst phase
SG1
to SG4 GND SG5 16k
SG3
θPAL1/2
SG1 to SG3:
No signal,
SG4: SIN wave,
3.58MHz
0.5Vp-p
SG5: CSYNC
TTL level
3.58MHz component
measured. Fig. 6
SG1 to SG3:
No signal,
SG4: SIN wave,
4.43MHz
0.5Vp-p
SG5: CSYNC
TTL level
Fig. 6
∗ Clamp voltage: voltage appearing at Pin 9 when CSYNC is input.
–7–
0.9
1.0
1.1
125
135
145
215
225
235
deg
deg
deg
1
24
–8–
2V
2
0.1µ
SG2
S1
21
4
S1
75
20
5
NC
6
PAL
ICC2
A
16k
S2
SG4
SIN
0.5Vp-p
PAL
7
17
NC
8
5V
S3
NTSC
NC
75 B
9
2V
0.1µ
75 A
10
S4
BPF
75
DRIVER
15
75
220µ
PULSE
GEN
B-Y
Modulator
R-Y
Modulator
75
DRIVER
16
75
220µ
SYNC
ADD
PHASE
SHIFTER
Y/C
MIX
CLAMP
18
20k
NTSC
S5
SIN-PULSE
DELAY
47µ
5V
19
VIDEO
OUT
0.01µ
75 C
220µ
0.1µ
SG3
CLAMP
B-OUT
75
220µ
75 D
SG1 to SG3 100% color bar (1Vp-p max.)
0.1µ
SG1
S1
3
CLAMP
G-OUT
R-OUT
CLAMP
22
75
75
23
220µ
75 E
220µ
75 F
MATRIX
Electrical Characteristics Measurement Circuit
SG5
CSYNC
NC
11
0.1µ
5V
0.01µ
12
13
ICC1 A
REGULATOR
14
10µ 47k
47µ
CXA1645P/M
CXA1645P/M
Measuring Signals and Output Waveforms
SG5
SG4
SYNC
IN
0.5Vp-p
SCIN
f = 3.58MHz
2.0V
SG5
SYNC
IN
64µs
2.0V
64µs
0.8V
0.8V
4.5µs
10µs
SG1
RIN
1.0Vp-p
SG2
GIN
1.0Vp-p
4.5µs
Fig. 1
SG3
1.0Vp-p
BIN
SG1 to 3
RIN
2.5V
GIN
BIN
1.0Vp-p
BC point
YOUT
CVOUT
f = 200kHz
Vo (YB)
Vo (YW) Vo (YG)
Vo (YS)
Vo (YR)
DEF point
Fig. 4
ROUT
VO
GOUT
BOUT
Fig. 2
SG4
0.5Vp-p
SCIN
f = 3.58MHz
SG1 to 3
SG5
RIN
2.5V
GIN
BIN
1.0Vp-p
SYNC
IN
f = 200kHz/5MHz
DEF
BC point
ROUT
GOUT
BOUT
YOUT
CVOUT
2.0V
64µs
0.8V
4.5µs
10µs
VO
Fig. 3
fc = 20log
SG1
RIN
1.0Vp-p
SG2
GIN
1.0Vp-p
Vo (5MHz)
Vo (200kHz)
SG3
BIN
1.0Vp-p
SG4
C point
CVOUT
0.5Vp-p
SCIN
f = 3.58MHz/
4.43MHz
VO (BN)
VO (CG)
VO (CB)
VO (CR)
tD (B)
64µs
0.8V
A point
4.5µs
Vo (BN)
VO (BN)
Vo (BN)
C point
tW (B)
CVOUT
K (BP) =
Vo (BN)
B/BN =
COUT
VL
VL
G/BN =
tW (B)
2.0V
SG4
SYNC
IN
R/BN =
Vo (BN)
Vo (BN)
Vo (BN)
A point
COUT
Fig. 6
–9–
VO (CB)
VO (CG) VO (CR)
Fig. 5
VO (CR)
VO (BN)
VO (CG)
VO (BN)
VO (CB)
VO (BN)
CXA1645P/M
Application Circuit (NTSC mode)
R
OUT
220µ
G
OUT
220µ
B
OUT
VCC
CV
OUT
220µ
C
OUT
220µ
220µ
75
75
23
24
75
21
22
20k
75
19
20
1%
G-OUT
75
NC
18
VIDEO
OUT
R-OUT
10µ 47k
220µ
0.1µ
∗
47µ
0.01µ
+5V
Y
OUT
16
15
75
DRIVER
75
DRIVER
17
Y/C
MIX
75
B-OUT
13
14
REGULATOR
DELAY
SYNC
ADD
MATRIX
CLAMP
BPF
R-Y
Modulator
B-Y
Modulator
CLAMP
CLAMP
CLAMP
2
3
4
1
6
5
9
8
7
NC
0.1µ
PULSE
GEN
PHASE
SHIFTER
SIN-PULSE
NC
10
0.1µ
0.1µ
0.01µ
G
IN
47µ
SYNC
IN
SCIN
R
IN
12
11
NC
0.1µ
B
IN
∗ Metal film resistor ±1%
Application Circuit (PAL mode)
R
OUT
220µ
G
OUT
220µ
B
OUT
VCC
CV
OUT
220µ
C
OUT
220µ
0.01µ
75
24
75
23
75
16k
75
21
22
∗
1%
47µ
20
19
18
R-OUT
G-OUT
10µ 47k
220µ
75
75
17
Y/C
MIX
VIDEO
OUT
Y
OUT
220µ
NC
+5V
16
15
75
DRIVER
75
DRIVER
B-OUT
0.1µ
13
14
REGULATOR
SYNC
ADD
CLAMP
MATRIX
DELAY
BPF
R-Y
Modulator
B-Y
Modulator
1
CLAMP
CLAMP
CLAMP
2
3
4
SIN-PULSE
5
6
7
NC
0.1µ
PULSE
GEN
9
10
12
11
NC
0.1µ
0.1µ
0.1µ
G
IN
8
NC
SYNC
IN
SCIN
R
IN
PHASE
SHIFTER
B
IN
0.01µ
47µ
∗ Metal film resistor ±1%
Application circuits shown are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for
any problems arising out of the use of these circuits or for any infringement of third party patent and other right due to same.
– 10 –
CXA1645P/M
Description of Operation
Analog RGB signals input from Pins 2, 3 and 4 are clamped in the clamping circuit and output from Pins 23,
22 and 21, respectively.
The matrix circuit performs operations on each input signal, generating luminance signal Y and color
difference signals R-Y and B-Y. The Y signal enters the delay line to adjust delay time with the color signal C.
Then, after addition of the CSYNC signal input from Pin 10, the Y signal is output from Pin 16.
A subcarrier input from Pin 6 is input to the phase shifter, where its phase is sfited 90°. Then, the subcarrier
is input to the modulators and modulated by the R-Y signal and the B-Y signal. Modulated subcarriers are
mixed, sent to the band pass filter to eliminate higher harmonic components and finally output from Pin 15 as
the C signal. At the same time, Y and C signals are mixed and output from Pin 20 as the composite video
signal.
Burst Signal
The CXA1645P/M generates burst signals at the timing shown below according to the composite sync signal
input.
H synchronization
SYNC
IN
(TTL level)
tD (B) tW (B)
C VIDEO
OUT
Burst signal
COUT
tD (B)
tW (B)
V synchronization
ODD
SYNC
IN
EVEN
ODD
C VIDEO
OUT
EVEN
Burst signal
Synchronizing signal
– 11 –
CXA1645P/M
Notes on Operation
Be careful of the following when using the CXA1645P/M.
1. This IC is designed for image processing of personal computers and video games. When using the IC in
other video devices, make thorough investigations on image quality.
2. Be sure that analog RGB signals are input at 1.0Vp-p maximum and have low enough impedance. High
impedance may affect color saturation, hue, etc. Inputting RGB signals in excess of 1.3Vp-p may disable
the clamp operation.
3. The SC input (Pin 6) can be either a sine wave or a pulse in the range from 0.4 to 5.0Vp-p.
However, when a pulse is input, its phase may be shifted several degrees from that of the sine wave input.
In the IC, the SC input is biased to 1/2 VCC. Accordingly, when a 5.0Vp-p pulse is input and the duty factor
deviates from 50%, High- and Low-level pulse voltages may exceed VCC and GND in the IC, which causes
subcarrier distortion. In such a case, be very careful that the duty factor keeps to 50%.
4. When designing a printed circuit board pattern, pay careful attention to the routing of the VCC and GND
leads. To decouple the VCC and VREF pins, use tantalum, ceramic or other capacitors with good frequency
characteristics. Ground the capacitors by connections shown below as closely to each IC pin as possible.
Try to design the leads as short and wide as possible.
VCC1, VREF
VCC2
... GND1
... GND2
Design the pattern so that VCC (or VREF) is connected to GND via a capacitor at the shortest distance.
5. SC and SYNC input pulses
Attach a resistor and a capacitor to eliminate high-frequency components of SC (Figure A) and SYNC
(Figure B) before input.
Fig. A
2.2k
Fig. B
2.2k
5P
47P
Be careful not to input pulses containing high-frequency components. Otherwise, high-frequency
components may flow into VCC, GND and peripheral parts, resulting in malfunctions.
6. Connecting an external resistor to the 75Ω driver output pin
A capacitance of several dozen picofarads at each pin may start oscillation. To prevent oscillation, design
the pattern so that a 75Ω resistor is mounted near the pin (see Figure C).
Fig. C
∗
∗
75
∗ Make these leads short.
When any of the 75Ω driver output pins is not in use, leave it unconnected and design the pattern so that
no parasitic capacitance is generated on the printed circuit board.
– 12 –
CXA1645P/M
7. VREF pin (Pin 14)
Do not connect this pin to an external load that might cause AC signals to flow, which will cause IC
malfunctions. When connecting a DC load, make sure that the current flowing from this pin is kept below
2mA.
8. YTRAP pin (Pin 17)
There are the following two means of reducing cross color generated by subcarrier frequency components
contained in the Y signal.
(1) Install a capacitor of 30 to 68pF between YTRAP and GND. Decide the capacitance by conducting image
evaluation, etc., giving consideration to both cross color and resolution.
Relations between capacitance and image quality are as follows:
(2)
Capacitance
30pF ←→ 68pF
Cross color
Resolution
Large ←→ Small
High ←→ Low
17
C
Connect a capacitor C and an inductor L in series between YTRAP and GND. When the subcarrier
1
frequency is fo, the values C and L are determined by the equation fo =
. Decide the values in
2π √LC
image evaluation, etc., giving consideration to both cross color and resolution.
Relations between inductor values and image quality are as follows:
Inductor value
Small ←→ Large
Cross color
Resolution
Large ←→ Small
High ←→ Low
17
C
L
For instance, L = 68µH and C = 28pF are recommended for NTSC. It is necessary to select an inductor L
with a sufficiently small DC resistance. Method (2) is more useful for achieving a higher resoluation than
method (1). When an even higher resolution is necessary, use of the S terminal (YOUT and COUT) is
recommended.
9. Driving COUT (Pin 15), YOUT (Pin 16), CVOUT (Pin 20), and B.G.R OUT (Pins 21, 22 and 23) outputs
In Pin Description, "Capable of driving a 75Ω load" means that the pin can drive a capacitor +75Ω +75Ω
load shown in the figure below. In other words, the pin is capable of driving a 150Ω load in AC.
75Ω
220µF
PIN
75Ω
Keep in mind that the pin is incapable of driving a 150Ω load in DC load in DC direct coupling.
10. This IC employs a number of 75Ω driver pins, so oscillation is likely to occur when measures described in
Nos. 4 and 6 are not taken thoroughly. Be very careful of oscillation in printed circuit board design and
carry out thorough investigations in the actual driving condition.
– 13 –
CXA1645P/M
Package Outline
Unit: mm
CXA1645P
+ 0.1
05
0.25 – 0.
24PIN DIP (PLASTIC) 400mil
+ 0.4
30.2 – 0.1
10.16
13
1
+ 0.3
8.5 – 0.1
24
0° to 15°
12
+ 0.4
3.7 – 0.1
3.0 MIN
0.5 MIN
2.54
0.5 ± 0.1
1.2 ± 0.15
PACKAGE STRUCTURE
PACKAGE MATERIAL
EPOXY RESIN
SONY CODE
DIP-24P-01
LEAD TREATMENT
SOLDER PLATING
EIAJ CODE
∗DIP024-P-0400-A
LEAD MATERIAL
COPPER / 42 ALLOY
PACKAGE WEIGHT
2.0g
JEDEC CODE
CXA1645M
24PIN SOP (PLASTIC)
+ 0.4
15.0 – 0.1
24
+ 0.4
1.85 – 0.15
13
6.9
+ 0.2
0.1 – 0.05
12
0.45 ± 0.1
1.27
+ 0.1
0.2 – 0.05
0.5 ± 0.2
1
7.9 ± 0.4
+ 0.3
5.3 – 0.1
0.15
± 0.12 M
PACKAGE STRUCTURE
SONY CODE
SOP-24P-L01
EIAJ CODE
∗SOP024-P-0300-A
JEDEC CODE
MOLDING COMPOUND
EPOXY/PHENOL RESIN
LEAD TREATMENT
SOLDER PLATING
LEAD MATERIAL
COPPER ALLOY / 42ALLOY
PACKAGE WEIGHT
0.3g
– 14 –