1
CXA1779P
E94510-ST
Predriver for High Resolution Computer Displays
Description
The CXA1779P is a bipolar IC developed for high
resolution computer displays.
Features
Wide bandwidth (150MHz/3dB typ.)
RGB single package
Permits RGB common and independent contrast
control
Permits RGB independent pedestal level control
Input D-range: 0.7Vp-p (min.)
Applications
High resolution computer displays
Structure
Bipolar silicon monolithic IC
Block Diagram and Pin Configuration
(Top View)
Absolute Maximum Ratings
Supply voltage
Vcc
14
V
Operating temperature
Topr 20 to +75
C
Storage temperature
Tstg 65 to +150 C
Allowable power dissipation P
D
2.8
W
Recommended Operating Conditions
Supply voltage
Vcc
12 0.6
V
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.
28 pin DIP (Plastic)
PEDESTAL
CLAMP
1.7V
CLP
SYNC
SLICE
OUTPUT-
BUFFER
BLANKING
ADD
GAIN
+15dB
BLK
BRIGHTNESS
CONTROL
CLP
B CONTRAST
CONTROL
PIX
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
1
PEDESTAL
CLAMP
1.7V
CLP
SYNC
SLICE
OUTPUT-
BUFFER
BLANK INC
ADD
GAIN
+15dB
BLK
BRIGHTNESS
CONTROL
CLP
R CONTRAST
CONTROL
PEDESTAL
CLAMP
1.7V
CLP
SYNC
SLICE
OUTPUT-
BUFFER
BLANKING
ADD
GAIN
+15dB
BLK
BRIGHTNESS
CONTROL
CLP
G CONTRAST
CONTROL
PIX
PIX
RGB
CONTRAST
CONTROL
PIX
CLAMP
PULSE-
SHAPE
BLANKING
PULSE-
SHAPE
CLP
BLK
Vcc
R IN
R DRV
R GND
G IN
G DRV
G GND
B IN
B DRV
B GND
REG
PIX
GND
CLP
R OUT
R S/H
R BRT
RD GND
G OUT
G S/H
G BRT
GO GND
B OUT
B S/H
B BRT
BO GND
BLK
N.C.
For the availability of this product, please contact the sales office.
2
CXA1779P
Pin Description
2
5
8
Vcc
GND
200A
129
200A
129
3
6
9
12
Vcc
GND
200A
129
200A
60k
Vcc
GND
20k
11
Pin
No.
1
2
5
8
3
6
9
12
4
7
10
11
13
17
21
25
12V
3.0V
--
0V
5V
0V
0V
Vcc
R IN
G IN
B IN
R DRV
G DRV
B DRV
PIX
R GND
G GND
B GND
REG
GND
BO GND
GO GND
RO GND
Power supply pin.
RGB input pins.
The pedestal level of the
input signal is 3.0V during
clamping.
Connect 0.01F in series as
the clamping capacitor.
RGB contrast adjustment
pins.
The variable range of the pin
voltages is from 0 to 5V.
RGB simultaneous contrast
adjustment pin.
The variable range of the pin
voltage is from 0 to 5V.
GND pins for the input
amplifier block.
Internal regulator stabilizing
pin.
5V regulator output pin.
Attaches the decoupling
capacitance (0.01F).
GND pin.
GND pins for the output stage
buffer amplifier block.
Symbol
Pin voltage
Equivalent circuit
Description
3
CXA1779P
14
Vcc
GND
15k
129
16
Vcc
GND
30k
129
18
22
26
Vcc
GND
200A
129
200A
50k
19
23
27
Vcc
GND
200A
1k
100A
20
24
28
Vcc
GND
14
--
CLP
Clamp pulse input pin.
Turns the input clamp and
the bright level adjustment
circuit on and off when high.
V
H
= 3V
V
L
= 1.5V
15
--
N.C.
Leave this pin open.
Connect to GND.
16
--
BLK
Blanking pulse input pin.
Threshold level at
approximately 2.25V.
V
H
= 3V
V
L
= 1.5V
18
--
B BRT
22
G BRT
26
R BRT
19
B S/H
23
G S/H
27
R S/H
20
B OUT
24
G OUT
28
R OUT
RGB bright level adjustment
pins.
The variable range of the pin
voltages is from 0 to 5V.
Pins to externally attach the
sample-and-hold capacitor
(0.01F).
RGB output pins.
Pin
No.
Symbol
Pin voltage
Equivalent circuit
Description
4
CXA1779P
S1 to S7: OFF
Input video signal 0.7Vp-p and measure
output signal amplitude V
OUT
. Calculate
the contrast gain from this V
OUT
.
CONT
MAX
[dB] = 20log
S1 to S7: OFF
CLP pulse width: 300ns
Measure the pedestal level of the RGB
output signal.
S1 to S7: OFF
Input video signal 0.7Vp-p and measure
the variable width of output signal V
OUT
.
Gain difference [dB]
= 20log
No.
Item
Symbol
Measurement contents
Min.
Typ.
Max.
Unit
1
Current
consumption
Icc
S1 to S7: OFF
Input signal: None
50
88
120
mA
2
Frequency
response
f
100MHz
S1 to S7: ON
Input continuous 1MHz and 100MHz
sine waves at 0.7Vp-p, and measure the
gain difference of the output amplitudes.
Gain difference [dB]
= 20log
3
1.5
--
dB
3
Contrast
control
CONT
MAX
13
14
--
dB
5
Sub contrast
gain
DRVgain
--
6
--
dB
4
Brightness
control
BRTmax
BRTmin
--
3.5
--
V
--
1.9
--
Electrical Characteristics
(Ta = 25C, Vcc = 12V, See Electrical Characteristics Measurement Circuit.)
(
)
(
)
V
OUT
1M
V
OUT
100M
(
)
V
OUT
DRVmax
V
OUT
DRVmin
RGB input signal (RGB input pin)
0.35V
0.7Vpp
GND
CLP potential
0.7
V
OUT
0.7Vpp
RGB input signal
Measuring is possible with or without a sync signal.
RGB output signal
Pedestal level
Measuring is possible with or without a sync signal.
GND
Measuring is possible with or without a sync signal.
RGB output signal
DRVmax
DRVmin
5
CXA1779P
6
Input D-range
D rang
S1 to S7: OFF
Measure the level which maintains the
output gain when the input video signal
level is varied.
--
0.8
--
Vp-p
7
Minimum
clamp pulse
width
CLPmin
S1 to S7: OFF
Measure the clamp pulse width where
the pedestal level of output signal V
OUT
does not fluctuate.
--
300
--
ns
CLP pulse
Pulse width
Video input
No.
Item
Symbol
Measurement contents
Min.
Typ.
Max.
Unit
6
CXA1779P
Electrical Characteristics Measurement Circuit
+
VIN
S2
1k
10k
Vcc
+
0.01
VIN
S3
1k
10k
Vcc
12V
10
+
VIN
S1
1k
10k
Vcc
4V
0.1
4V
+
S7
CLP
+
0.01
S6
0.01
S5
VOUT
0.01
S4
2.5V
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
1
9V
BLK
V
c
c
R
I
N
R
D
R
V
R
G
N
D
G
I
N
G
D
R
V
G
G
N
D
B
I
N
B
D
R
V
B
G
N
D
R
E
G
P
I
X
G
N
D
C
L
P
R
O
U
T
R
S
/
H
R
B
R
T
R
O
G
N
D
G
O
U
T
G
S
/
H
G
B
R
T
G
O
G
N
D
B
O
U
T
B
S
/
H
B
B
R
T
B
O
G
N
D
B
L
K
N
.
C
.
0.01
0.01
VOUT
VOUT
Application Circuit
12V
10
5V
0.1
0.01
V
c
c
R
I
N
R
D
R
V
R
G
N
D
G
I
N
G
D
R
V
G
G
N
D
B
I
N
B
D
R
V
B
G
N
D
R
E
G
P
I
X
G
N
D
C
L
P
R
O
U
T
R
S
/
H
R
B
R
T
R
O
G
N
D
G
O
U
T
G
S
/
H
G
B
R
T
G
O
G
N
D
B
O
U
T
B
S
/
H
B
B
R
T
B
O
G
N
D
B
L
K
N
.
C
.
0.01
R in
0.7Vpp
0.01
G in
0.7Vpp
0.01
B in
0.7Vpp
CLP in
5V
5V
5V
5V
0.01
5V
0.01
5V
BLK in
C
A
T
H
O
D
E
D
R
I
V
E
R
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
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.
7
CXA1779P
Description of Operation
1. Contrast control
The contrast for RGB IN (Pins 2, 5 and 8) input signals is adjusted using a DC externally input to the PIX
pin (Pin 12). In addition, the contrast for each RGB channel can be adjusted independently using a DC
externally input to the DRV pins (Pins 3, 6 and 9). (See Graphs 1 and 2.)
2. Pedestal clamp and brightness control
The pedestal clamp clamps the pedestal level when the CLP pin (Pin 14) is high. The RGB IN pin voltage at
the pedestal is approximately 3.2V when the pedestal is clamped. The CLP pin threshold level is 3V for V
H
and 1.5V for V
L
. (See Fig. 2.)
Using a DC externally input to the R, G and B BRT pins (Pins 26, 22 and 18), the brightness control
samples and holds the pedestal with the capacitance connected to the RGB SH pins (Pins 27, 23 and 19)
when the CLP pin (Pin 14) is high, thereby adjusting the pedestal level of the R, G and B channels. (See
Graph 3.)
3. Blanking additional function
Output is blanked when the BLK pin (Pin 16) is high. The BLK pin threshold level is 3V for V
H
and 1.5V for
V
L
. See the Example of Input/Output Signals for output signal levels. The output signal is 0.3V during the
blanking interval. (See Figs. 4 and 5.)
8
CXA1779P
Example of Input/Output Signals
RGB IN
Pins 2, 5 and 8
0.7Vpp (Typ.)
Clamp DC voltage
3.2V
GND = 0V
CLP pulse
Pin 14
t
C
L
P
t
CLP
300ns
V
H
= 3V
V
L
= 1.5V
Adjust the pedestal level
with the BRT pin.
GND
Adjust the contrast
with the PIX and DRV pins.
RGB OUT
Pins 20, 24 and 28
When a sync signal is added to the RGB input signal, after the signal is sliced into approximately
60mVp-p inside the IC, it is amplified by the gain from the PIX and DRV pins and output.
V
H
= 3V
V
L
= 1.5V
BLK
Pin 16
RGB OUT
Pins 20, 24 and 28
(During BLK pulse input)
Approximately 0.3V (typ.)
GND
(When the blanking
function is operating)
Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
9
CXA1779P
Example of Representative Characteristics
Graph 1. Contrast control (RGB common) characteristics
20
10
0
10
20
0
1
2
3
4
5
O
u
t
p
u
t
l
e
v
e
l
[
d
B
]
PIX [V]
Graph 2. DRV control (RGB independent) characteristics (Gch)
2
0
2
4
6
0
1
2
3
4
5
G DRV [V]
O
u
t
p
u
t
l
e
v
e
l
[
d
B
]
PIX
Graph 3. BRT control characteristics
4
3
2
1
0
1
2
3
4
5
P
e
d
e
s
t
a
l
l
e
v
e
l
[
V
]
G BRT [V]
Pin name
Pin voltage
12
PIX
3
R DRV
6
G DRV
9
B DRV
26
R BRT
22
G BRT
18
B BRT
5
G IN
0 to 5
[V]
4
[V]
4
[V]
4
[V]
2.5
[V]
2.5
[V]
2.5
[V]
0.65 [Vpp]
Input conditions for each control pin
Pin name
Pin voltage
12
PIX
3
R DRV
6
G DRV
9
B DRV
26
R BRT
22
G BRT
18
B BRT
5
G IN
4
[V]
4
[V]
0 to 5
[V]
4
[V]
2.5
[V]
2.5
[V]
2.5
[V]
0.65 [Vpp]
Input conditions for each control pin
Pin name
Pin voltage
12
PIX
3
R DRV
6
G DRV
9
B DRV
26
R BRT
22
G BRT
18
B BRT
5
G IN
2.5
[V]
2.5
[V]
2.5
[V]
2.5
[V]
2.5
[V]
0 to 5
[V]
2.5
[V]
0.65 [Vpp]
Input conditions for each control pin
10
CXA1779P
Package Outline
Unit: mm
SONY CODE
EIAJ CODE
JEDEC CODE
PACKAGE STRUCTURE
PACKAGE MATERIAL
LEAD TREATMENT
LEAD MATERIAL
PACKAGE MASS
EPOXY RESIN
SOLDER PLATING
COPPER ALLOY
DIP-28P-03
DIP028-P-0600
4.2g
28PIN DIP (PLASTIC)
37.8 0.1
+ 0.4
28
15
1
14
2.54
0.5 0.1
1.2 0.15
3
.
0
M
I
N
0
.
5
M
I
N
4
.
6
0
.
1
+
0
.
4
1
5
.
2
4
1
3
.
0
0
.
1
+
0
.
3
0
.2
5
0
.0
5
+
0
.1
0 to 15
1.All mat surface type.
Two kinds of package surface:
2.Center part is mirror surface.
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