ISO-9001 CERTIFIED BY DSCC
M.S.KENNEDY CORP.
FEATURES:
HIGH SPEED/HIGH VOLTAGE
VIDEO AMPLIFIER
1902
SERIES
(315) 701-6751
4707 Dey Road Liverpool, N.Y. 13088
100V
PP
Output Signal into 10
P
F
Ultra Fast Transition Times-2.5nS
User Adjustable Contrast and Brightness
TTL Compatible Blanking
On Board DC Reference Output
Customized Versions Available Upon Request
Available to DSCC SMD 5962-8997201HX
MIL-PRF-38534 CERTIFIED
DESCRIPTION:
The MSK 1902 Series of high speed, high voltage video amplifiers was designed to drive the cathode of today's
high performance CRT's. The MSK 1902 has user adjustable contrast and brightness levels and also comes with a
blanking function. The MSK 1902 can be directly connected to many video sources including RS170, RS343 and high
speed video D/A converters. The MSK 1902 is available in four versions for different applications. The MSK 1902-0
has no internal high voltage resistor or inductor allowing the user to dissipate much of the power externally. The MSK
1902-2, MSK 1902-4 and the MSK 1902-6 each have an internal resistor-inductor designed for optimum bandwidth.
The MSK 1902-6 has slightly lower bandwidth but can be operated from up to +130V. Each version of the MSK
1902 is packaged in a 30 pin power flatpack that can be directly connected to a heat sink using standard 4-40
screws.
EQUIVALENT SCHEMATIC
TYPICAL APPLICATIONS
Helmet Mounted Displays
High Resolution RGB Displays
High Resolution Monochrome Displays
Automatic Test Equipment
1
2
3
4
5
6
7
8
9
10
PIN-OUT INFORMATION
GND
GND
Blank
V
EE
V
EE
V
EE
-Input
+Input
GND
GND
1
11
12
13
14
15
16
17
18
19
20
V
GAIN
V
OFF
V
REF
GND
GND
+V
HV
RES
+V
HV
RES
GND
GND
+V
HV
21
22
23
24
25
26
27
28
29
30
+V
HV
NC
Output
NC
Cath. Current R
TN
V
CC
V
CC
GND
GND
GND
Rev. A 5/02
ABSOLUTE MAXIMUM RATINGS
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+V
HV
ELECTRICAL SPECIFICATIONS
Parameter
STATIC
Quiescent Current
High Voltage Supply
INPUT
Input Bias Current
Blank Input Current
Offset Adjust Input Current
Gain Adjust Input Current
Blank Input Pulse Width 2
Common Mode Rejection Ratio 2
Input Impedance 2
Input Capacitance
Blank Mode Input
Rejection
∆V
2
3
3
Gain Adjust Rejection
∆V
2
Internal Rp
OUTPUT
Reference Output Voltage
∆V
Blank Mode
∆V
Min Offset
∆V
Max Offset
Voltage Gain
Output Voltage High
Output Voltage Low
Transition Times
Linearity Error 2
Gain Linearity 2
Thermal Distortion 2
I
OUT
<2mA
∆V=V
HV
-V
OUT
V
OFF
=1V
V
BLANK
=2.4V V
GAIN
=5V
∆V=V
HV
-V
OUT
V
OFF
=0V V
GAIN
=3V
∆V=V
HV
-V
OUT
V
OFF
=5V
V
IN
=0.6V F=10KHz V
GAIN
=3V Both Inputs
V
GAIN
=3V F=10KHz
V
GAIN
=3V F=10KHz
V
IN
=0.6V V
OUT
=Max TR=TF<0.5nS
V
GAIN
=4V V
OFF
=1V V
CM
=0.5V
V
OFF
=1V V
IN
=0.2V V
CM
=0.5V
1,2,3
1,2,3
1,2,3
1
2,3
4
4
4
4
-
-
-
5.2
5.5
5.8
5.2 5.5
5.8
5.2
5.5
5.8
5.2 5.5
-3xRp Rp
0
32
32
3
42
42
5.8
3xRp
10
52
52
-
20
8
±2
±2
±2
V
mV
V
V
V
V/V
V
V
nS
%GS
%
%GS
2
3
V
CM
=0V
V
BLANK
=0.4V
V
BLANK
=2.4V
V
OFF
=1V
V
GAIN
=5V
Normal Operation
V
CM
=±0.5V F=10Hz
Either Input F=DC
Either Input
V
BLANK
=2.4V V
IN
=0.3V
∆V=V
HV
-V
OUT
∆V
GAIN
=5V
1
2,3
1
1
1
1
-
-
-
-
-
-
-
-
-
-
-
-
-
-
30
-
10
-
-
-
25
-
±1 ±50
±5 ±250
500 600
300 400
2
2
-
40
20
2
10
10
-
-
-
-
-
-
-
-
-
-
30
-
10
-
-
-
25
±1 ±50
±5 ±250
500 600
300 400
2
2
-
40
20
2
10
10
-
-
-
-
-
-
-
-
-
-
30
-
10
-
-
-
25
±1 ±50
±5 ±250
500 600
300 400
2
2
-
40
20
2
10
10
-
-
-
-
-
-
-
-
-
-
30
-
10
-
-
-
25
±1 ±50
±5 ±250
500 600
300 400
2
2
-
40
20
2
-
10
10
-
-
-
-
µA
µA
µA
µA
µA
µA
nS
dB
KΩ
pF
2 3
3
V
CM
=0V @ +15V
V
CM
=0V @ -10.5V
T
C
≤
125°C
Q
OUT
/Q
CAS
1,2,3
1,2,3
-
-
-
-
30
-
75
100
-
-
-
75
100
-
-
30
-
75
70
32
100
75
35
-
-
-
75
100
mA
mA
V
°C/W
-75 -100
100 110
32
35
-75 -100
32
35
-75 -100
-75 -100
32
35
Test Conditions
1
MSK1902-2
MSK1902-4
Group A MSK1902-0
Subgroup Min. Typ. Max. Min. Typ. Max. Min. Typ. Max.
MSK1902-6
Min. Typ. Max.
30 100 110
30 120 130
Thermal Resistance to Case
- ±2xRp
- ±10xRp
30
0
-
-
- ±2xRp
- ±10xRp
30
-
- ±2xRp
- ±10xRp
30
-
±2xRp mV
mV
dB
Ω
- ±10xRp
30
-
Power Supply Rejection Ratio 2 +V
CC
and -V
EE
=Nom ±5%
380 400 420
190 200 210
380 400 420
-3xRp Rp 3xRp -3xRp Rp 3xRp -3xRp Rp 3xRp
0
32
28
72
95
-
-
-
-
-
3
42
42
98
15
3.5
-
-
-
10
52
56
-
20
5.5
±2
±2
±2
0
32
32
95
-
-
-
-
3
42
42
98
10
2.8
-
-
-
10
52
52
-
20
4.0
±2
±2
±2
0
16
16
36
65
-
-
-
-
-
3
21
21
55
68
10
2.0
-
-
-
6
26
26
68
-
20
2.8
±2
±2
±2
110 138
72 110 138
72 120 145
115 118
-
-
-
-
10
6
-
-
-
NOTES:
1
2
3
4
5
6
7
+V
CC
= +15V, -V
EE
= -10.5V, V
BLANK
=0.4V, V
GAIN
= V
OFF
= ±V
IN
= 0V, C
L
=10pF, V
HV
=typical value and T
C
=25°C unless otherwise specified.
Guaranteed by design but not tested. Typical parameters are representative of actual device performance but are for reference only.
R
P
=Internal R
P
except MSK 1902-0. External value = 400Ω unless otherwise specified for the MSK 1902-0.
Industrial grade and "E" suffix devices shall be tested to subgroups 1 and 4 unless otherwise specified.
Military grade devices ("B" suffix) shall be 100% tested to subgroups 1,2,3 and 4.
Subgroups 5 and 6 testing available upon request.
Subgroup 1,4 T
A
=T
C
=+25°C
2,5 T
A
=T
C
=+125°C
3,6 T
A
=T
C
=-55°C
2
Rev. A 5/02
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+V
CC
-V
EE
V
IN
V
IC
V
GAIN
V
OFF
T
J
I
RP
T
C
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High Voltage Supply (1902-0)
(1902-2)
(1902-4)
(1902-6)
Positive Supply Voltage
Negative Supply Voltage
Differential Input Voltage
Common Mode Input Voltage
Gain Adjust Input Voltage
Offset Adjust Input Voltage
+110V
+110V
+75V
+130V
+17V
-12V
2V
±2V
-0.6 to +6V
-0.6 to +6V
V
BLANK
I
REF
T
ST
T
LD
-0.6 to +6V
Blank Input Voltage
5mA
Reference Output Current
Storage Temperature Range -65°C to +150°C
300°C
Lead Temperature Range
(10 Seconds)
175°C
Junction Temperature
290mA
Current Through Rp
Case Operating Temperature Range
-55°C to +125°C
(All Devices B/E Suffix)
-40°C to +85°C
(All Devices No Suffix)
Units
APPLICATION NOTES
POWER SUPPLIES
The input stage of the MSK 1902 requires power supplies of
+15V and -10.5V for optimum operation. The negative power
supply can be increased to -12V if -10.5V is not available, but
additional power dissipation will cause the internal temperature
to rise. Both low voltage power supplies should be effectively
decoupled with tantalum capacitors (at least 4.7µF) connected
as close to the amplifier's pins as possible. The MSK 1902 has
internal 0.01µF capacitors that also improve high frequency
performance. In any case, it is also recommended to put 0.1µF
decoupling capacitors on the +15V and -10.5V supplies as
well.
The high voltage power supply (+V
HV
) is connected to the
amplifier's output stage and must be kept as stable as possible.
The internal or external Rp is connected to +V
HV
and as such,
the amplifier's DC output is directly related to the high voltage
value. The +V
HV
pins of the hybrid should be decoupled to
ground with as large a capacitor as possible to improve output
stability.
VIDEO INPUTS
The video input signals should be kept below ±2V
MAX
total,
including both common mode offset and signal levels. The in-
put structure of the MSK 1902 was designed for ±0.714Vpp
RS343 signals. If either input is not used it should be con-
nected directly to the analog ground or through a 25Ω resistor
to ground if input offset currents are to be minimized.
OUTPUT PROTECTION
The output pin of the MSK 1902 should be protected from
transients by connecting reverse biased ultra-low capacitance
diodes from the output pin to both +V
HV
and ground. The
output can also be protected from arc voltages by inserting a
small value (50-100Ω) resistor in series with the amplifier out-
put. This resistor will reduce system bandwidth along with the
load capacitance, but a series inductor can reduce the problem
substantially.
V
GAIN
CONTROL INPUT
The V
GAIN
control (contrast) input is designed to allow the
user to vary the video gain. By simply applying a DC voltage
from 0V to V
REF
, the video gain can be linearly adjusted from 0
to 80V/V. The V
GAIN
input should be connected to the V
REF
pin
through a 5KΩ pot to ground. For convenient stable gain adjust-
ment, a 0.1µF bypass capacitor should be connected near the
V
GAIN
input pin to prevent output instability due to noisy sources.
Digital gain control can be accomplished by connecting a D/A
converter to the V
GAIN
pin. However, some temperature track-
ing performance may be lost when using an external DC voltage
source other than V
REF
for gain adjustment.
The overall video output of the MSK 1902 can be character-
ized using the following expression:
Vpp=V
HV
-V
OUT
V
HV
-V
OUT
=(V
IN
) (V
GAIN
) (0.1) (Rp) (0.9)
Here is a sample calculation for the MSK 1902-2:
Given information:
V
IN
=0.7V
V
GAIN
=1VDC
Rp=400Ω (internal)
V
HV
=100VDC
V
HV
-V
OUT
=(0.7V) (1V) (0.1) (400Ω) (0.9)
V
HV
-V
OUT
=25.2V Nominal
The expected video output would swing from approximately
+100V to +74.8V assuming that V
OFF
=0V. This calculation
should be used as a nominal result because the overall gain may
vary as much as ±20% due to internal high speed device varia-
tions. Changing ambient conditions can also affect the video
gain of the amplifier by as much as 150 PPM/°C. It is wise to
connect all video amplifiers to a common heat sink to maximize
thermal tracking when multiple amplifiers are used in applica-
tions such as RGB systems. Additionally, only one of the V
REF
outputs should be shared by all three amplifiers. This voltage
should be buffered with a suitable low drift op-amp for best
tracking performance.
SUPPLY SEQUENCING
The power supply sequence is +V
HV
, +V
CC
, -V
EE
followed
by the other DC control inputs. If power supply sequencing is
not possible, the time difference between each supply should
be less than five milliseconds. If the DC control signals are
being generated from a low impedance source other than the
V
REF
output, reverse biased diodes should be connected from
each input (V
GAIN
, V
OFF
) to the +V
CC
pin. This will protect the
inputs until +V
CC
is turned on.
VIDEO OUTPUT
When power is first applied and V
IN
=V
GAIN
=V
OFF
=0V, the
output will be practically at the +V
HV
rail voltage. The output
voltage is a function of the value of Rp and also the V
GAIN
and
V
OFF
DC inputs. The maximum output voltage swing for any of
the MSK 1902 variants is determined by Vpp = (250mA) x
(Rp). The bandwidth of the amplifier largely depends on both
Rp and Lp.
Hybrid pins 16 and 17 are directly connected to Rp. Addi-
tional external resistance can be added to reduce power dissi-
pation, but slower transition times will result. If an additional
resistor is used, it must be low capacitive and the layout should
minimize capacitive coupling to ground (ie: no ground plane
under Rp).
The MSK 1902 series is conservatively specified with low
values for Lp which yield about 5% overshoot. Additional peak-
ing can be obtained by using a high self-resonant frequency
inductor in series with the Rp pins. Since this value of induc-
tance can be very dependent on circuit layout, it is best to
determine its value by experimentation. A good starting point
is typically 0.47µH for the MSK 1902-0 and 0.0047µH for the
remaining devices.
If external resistors or inductors are not used, be sure to
connect high frequency bypass capacitors directly from pins
16 and 17 to ground.
3
Rev. A 5/02
APPLICATION NOTES CON'T
V
OFF
CONTROL INPUT
The brightness (output offset) can be linearly adjusted by
applying a 0 to V
REF
DC voltage to the V
OFF
input pin. The
output quiescent voltage range is from approximately (5µA)
(Rp) to (100mA) (Rp) from +V
HV
. This control voltage is nor-
mally generated by connecting the V
OFF
control pin to a 5K
potentiometer between V
REF
and ground. The V
OFF
input pin
should be bypassed with a 0.1µF capacitor to ground placed as
close as possible to the hybrid. This DC voltage can be any
stable system source.
Keep hybrid power dissipation in mind when adjusting the
output quiescent voltage. Practically all of the voltage is seen
across Rp. This power must be taken into account when high
Rp currents are used. If the quiescent level is set too close to
+V
HV
, the power dissipation will be minimal but the rise time
will suffer slightly. If the quiescent level is set too far from
V
HV
, the power dissipation will increase dramatically and the
output fall time will be limited. The output black level is obvi-
ously dependent on system requirements but a little experi-
mentation will strike the optimum balance between power dis-
sipation and bandwidth. Total current through Rp should be
limited to less than 290mA when operating from power sup-
plies greater than 90V. The gain adjust alone can set the AC
current to 250mA (ie: 250mApp=100Vpp/400Ω). Typically,
most applications use about 10V from +V
HV
for a black level.
BLANK INPUT
The video input can be electrically disconnected from the
amplifier by applying a TTL high input to the blank pin. When
this occurs, the output will be set to approximately +V
HV
. The
V
GAIN
and V
OFF
control pins have little or no effect on the out-
put when it is in blank mode.
When the TTL compatible blank input is not used, the pin
must be connected to ground to enable the amplifier. The blank
input will float high when left unconnected which will disable
the video output.
V
REF
OUTPUT
The MSK 1902 has an on board buffered DC zener reference
output. The V
REF
output is nominally 5.5V DC and has full tem-
perature test limits of 5.2V to 5.8V DC. This output is provided
for gain and offset adjustment and can source up to 4mA of
current.
THERMAL MANAGEMENT
The MSK 1902 package has mounting holes that allow the
user to connect the amplifier to a heat sink or chassis. Since
the package is electrically isolated from the internal circuitry,
mounting insulators are not required or desired for best thermal
performance. Use 4 to 6 inch/pounds for mounting the device
to the heat sink.
The power dissipation of the amplifier depends mainly on the
load requirements, bandwidth, pixel size, black level and the
value of Rp. The following table illustrates a few examples:
PERCENT OF SIGNAL
BLANK
100%
20%
100%
20%
BLACK
0%
40%
0%
40%
WHITE
0%
40%
0%
40%
OUTPUT
AVE. Pd
0W
13.3W
0W
8.4W
TOTAL
AVE. Pd
2.5W
15.7W
2.5W
10.6W
DEVICE
TYPE
1902-6
1902-6
1902-4
1902-4
+VHV
120V
120V
70V
70V
BLACK
LEVEL
110V
110V
65V
65V
WHITE
LEVEL
20V
20V
15V
15V
OUTPUT
VOLTAGE
0V
90V
0V
50V
This table does not include power dissipation due to output switching since this is dependent on individual load requirements. The input stage
power dissipation is typically 2.5 watts and is essentially independent of output levels.
RESOLUTION TABLE FOR A TYPICAL CRT
Display
Resolution
Maximun
Pixel
Time
182nS
52nS
38nS
26nS
12.6nS
11nS
8.9nS
5.8nS
2.8nS
860pS
Minimum Pixel
Clock
Frequency
5MHz
19MHz
26MHz
38MHz
80MHz
90MHz
112MHz
170MHz
360MHz
1.2GHz
Required Rise Time
at CRT
Required System
Bandwidth
(F
-3dB
)
6MHz
20MHz
28MHz
41MHz
84MHz
95MHz
120MHz
180MHz
380MHz
1.23GHz
320 x 200
640 x 350
640 x 480
800 x 560
1024 x 900
1024 x 1024
1280 x 1024
1664 x 1200
2048 x 2048
4096 x 3300
60nS
17nS
12.5nS
8.6nS
4.2nS
3.7nS
2.9nS
1.9nS
1nS
280pS
All data assumes retrace time equal to 30% of frame time and a 60Hz refresh rate.
4
Rev. A 5/02
TYPICAL CONNECTION CIRCUIT
The connection circuit shown above is for the MSK 1902-0 evaluation board. The Rp and Lp are external compo-
nents and must not be located near ground planes if possible. A high quality resistor such as Bradford Electronics P/
N FP10-400 is required for optimum response times. Use an inductor with a high self-resonant frequency that can
withstand the currents required for the application.
When using the other variants of the MSK 1902, place an additional bypass capacitor on pins 16 and 17 if series
(Rp and Lp) components are not utilized. The pin should connect to +V
HV
with a short low impedance path.
For additional application information, please contact MSK. Evaluation amplifiers with test boards are available upon
request.
NOTES:
5
Rev. A 5/02
