NSC LM1203N Datasheet
LM1203 RGB Video Amplifier System
LM1203 RGB Video Amplifier System
January 1996
General Description
The LM1203 is a wideband video amplifier system intended
for high resolution RGB color monitor applications. In addition to three matched video amplifiers, the LM1203 contains
three gated differential input black level clamp comparators
for brightness control and three matched attenuator circuits
for contrast control. Each video amplifier contains a gain set
or ‘‘Drive’’ node for setting maximum system gain (Av
e
to 10) as well as providing trim capability. The LM1203 also
contains a voltage reference for the video inputs. For high
resolution monochrome monitor applications see the
LM1201 Video Amplifier System datasheet.
Block and Connection Diagram
Features
Y
Three wideband video amplifiers (70 MHz
Y
Inherently matched (g0.1 dB or 1.2%) attenuators for
contrast control
Y
Three externally gated comparators for brightness control
Y
Provisions for independent gain control (Drive) of each
4
video amplifier
Y
Video input voltage reference
Y
Low impedance output driver
@
b
3dB)
FIGURE 1
Order Number LM1203N
See NS Package Number NA28F
C
1996 National Semiconductor Corporation RRD-B30M56/Printed in U. S. A.
TL/H/9178
TL/H/9178– 1
Absolute Maximum Ratings
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales
Office/Distributors for availability and specifications.
Supply Voltage, V
(Note 1) 13.5V
Voltage at Any Input Pin, V
Video Output Current, I16, 20 or 25 28 mA
Power Dissipation, P
(Above 25
Thermal Resistance, i
Junction Temperature, T
Pins 1, 13, 23, 28
CC
IN
D
C) Derate Based on iJAand T
§
JA
J
t
V
CC
t
V
GND
IN
2.5W
J
50§C/W
150§C
Storage Temperature Range, T
STG
b
65§Ctoa150§C
Lead Temperature, (Soldering, 10 sec.) 265§C
ESD susceptibility 1 kV
Human body model: 100 pF discharged through a 1.5 kX
resistor
Operating Ratings (Note 9)
Temperature Range 0
Supply Voltage (VCC) 10.8VsV
Cto70§C
§
s
CC
13.2V
Electrical Characteristics See Test Circuit
DC Static Tests S17, 21, 26 Open; V12
e
6V; V14e0V; V15e2.0V unless otherwise stated
(Figure 2)
,T
A
e
25§C; V
Label Parameter Conditions Typ
e
e
V
CC2
12V
CC1
Tested Design Units
Limit (Note 2) Limit (Note 3) (Limits)
Is Supply Current VCC1 only 73 90.0 mA(max)
V11 Video Input Reference Voltage
2.4
2.2 V(min)
2.6 V(max)
lb Video Input Bias Current Any One Amplifier 5.0 20 mA(max)
V14 l Clamp Gate Low Input Voltage Clamp Comparators On 1.2 0.8 V(max)
V14 h Clamp Gate High Input Voltage Clamp Comparators Off 1.6 2.0 V(min)
I14 l Clamp Gate Low Input Current V14e0V
b
0.5
b
5.0 mA(max)
I14 h Clamp Gate High Input Current V14e12V 0.005 1 mA(max)
lclampaClamp Cap Charge Current V5, 8 or 10e0V 850 500 mA(min)
lclampbClamp Cap Discharge Current V5, 8 or 10e5V
b
850
b
500 mA(min)
Vol Video Output Low Voltage V5, 8 or 10e0V 0.9 1.25 V(max)
Voh Video Output High Voltage V5, 8 or 10e5V 8.9 8.2 V(min)
DVo(2V) Video Output Offset Voltage Between Any Two Amplifiers
e
2V
V15
DVo(4V) Video Output Offset Voltage Between Any Two Amplifiers
V15e4V
AC Dynamic Tests S17, 21, 26 Closed; V14
e
0V; V15e4V; unless otherwise stated
Symbol Parameter Conditions Typ
Av max Video Amplifier Gain V12e12V, V
e
560 mVp-p 6.0 4.5 V/V(min)
IN
DAv 5V Attenuation@5V Ref: Av max, V12e5V
DAv 2V Attenuation@2V Ref: Av max, V12e2V
Av match Absolute gain match@Av max V12e12V (Note 5)
DAv track1 Gain change between amplifiers V12e5V (Notes 5, 8)
DAv track2 Gain change between amplifiers V12e2V (Notes 5, 8)
THD Video Amplifier Distortion V12e3V, V
e
1 Vp-p 0.5 %
O
f(b3 dB) Video Amplifier Bandwidth V12e12V,
e
(Notes 4, 6) V
t
r
t
f
Output Rise Time (Note 4) V
Output Fall Time (Note 4) V
100 mV
O
e
O
e
O
rms
4 Vp-p 5 ns
4 Vp-p 7 ns
g
0.5
g
0.5
g
50 mV(max)
g
50 mV(max)
Tested Design Units
Limit (Note 2) Limit (Note 3) (Limits)
b
10 dB
b
40 dB
g
0.5 dB
g
0.1
g
0.3
g
0.5 dB(max)
g
0.7 dB(max)
70 MHz
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AC Dynamic Tests S17, 21, 26 Closed; V14
Symbol Parameter Conditions Typ
Vsep Video Amplifier 10 kHz Isolation V12e12V (Note 7)
10 kHz
Vsep Video Amplifier 10 MHz Isolation V12e12V (Notes 4, 7)
10 MHz
Note 1: VCCsupply pins 1, 13, 23, 28 must be externally wired together to prevent internal damage during VCCpower on/off cycles.
Note 2: These parameters are guaranteed and 100% production tested.
Note 3: Design limits are guaranteed (but not 100% production tested). These limits are not used to calculate outgoing quality levels.
Note 4: When measuring video amplifier bandwidth or pulse rise and fall times, a double sided full ground plane printed circuit board without socket is recommend-
ed. Video Amplifier 10 MHz isolation test also requires this printed circuit board.
Note 5: Measure gain difference between any two amplifiers. V
Note 6: Adjust input frequency from 10 kHz (Av
Note 7: Measure output levels of the other two undriven amplifiers relative to driven amplifier to determine channel separation. Terminate the undriven amplifier
inputs to simulate generator loading. Repeat test at f
Note 8: DAv track is a measure of the ability of any two amplifiers to track each other and quantifies the matching of the three attenuators. It is the difference in
gain change between any two amplifiers with the Contrast Voltage V12 at either 5V or 2V measured relative to an Av max condition V12
Av max the three amplifiers gains might be 17.4 dB, 16.9 dB, and 16.4 dB and change to 7.3 dB, 6.9 dB, and 6.5 dB respectively for V12
measured typical
Note 9: Operating Ratings indicate conditions for which the device is functional. See Electrical Specifications for guaranteed performance limits.
g
0.1 dB channel tracking.
ref level) to theb3 dB corner frequency (fb3 dB).
max
e
10 MHz for Vsepe10 MHz.
IN
e
0V; V15e4V; unless otherwise stated (Continued)
Tested Design
Limit (Note 2) Limit (Note 3)
b
65 dB
b
46 dB
e
1 Vp-p.
IN
e
12V. For example, at
e
5V. This yields the
Units
*Peaking capacitors. See Frequency Response
using various peaking cups graph on next page.
FIGURE 2. LM1203 Test Circuit
TL/H/9178– 2
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Typical Performance Characteristics
Contrast vs Frequency
Frequency Response Using
Various Peaking Caps
TL/H/9178– 11
TL/H/9178– 13
Crosstalk vs Frequency
TL/H/9178– 12
Attenuation vs Contrast Voltage
TL/H/9178– 14
Pulse Response
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Rise & Fall Times
e
Vert.
e
Horiz.
– – GND
TL/H/9178– 15
1V/Div.
10 ns/Div.
FIGURE 3. LM1203 Typical Application
TL/H/9178– 3
* 30X resistors are added to the input pins for protection against current surges coming through the 10 mF input capacitors. By increasing these resistors to well
over 100X the rise and fall times of the LM1203 can be increased for EMI considerations.
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