Monolithic Triple 3 ns CRT Driver
The LM2402 is an integrated high voltage CRT driver circuit
designed for use in high resolution color monitor applica-
tions. The IC contains three high input impedance, wide
band amplifiers which directly drive the RGB cathodes of a
CRT. Each channel has its gain internally set to −14 and can
drive CRT capacitive loads as well as resistive loads pre-
sented by other applications, limited only by the package’s
The IC is packaged in an industry standard 11 lead TO-220
molded plastic power package. See thermal considerations
on page 5.
n Rise/fall times typically 3.0/2.8 ns with 8 pF load at
n Well matched with LM2202 video preamps
n Output swing capability: 50 VPP for VCC = 80V
n 1V to 5V input range
n Stable with 0-20 pF capacitive loads and inductive
n Convenient TO-220 staggered lead package style
n Standard LM240X family pinout which is designed for
easy PCB layout
n CRT driver for color monitors with display resolutions up
to 1600 x 1200
n Pixel clock frequency up to 200 MHz
Schematic and Connection Diagrams
FIGURE 1. Simplified Schematic Diagram
Order Number LM2402T
© 1999 National Semiconductor Corporation DS101016
Absolute Maximum Ratings (Notes 1, 2)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Supply Voltage, VCC
Bias Voltage, VBB
Input Voltage, VIN
−0.5V to VBIAS + 0.5V
Storage Temperature Range, TSTG −65˚C to +150˚C
Lead Temperature (Soldering, <10 sec.)
Human Body Model
Conditions (Note 3)
VOUT (VCC = 80V, VBB = 12V)
+60V to +85V
+8V to +15V
+1V to +5V
+17V to +72V
−20˚C to +100˚C
Do not operate the part without a heat sink.
(See Figure 2 for Test Circuit)
Unless otherwise noted: VCC = +80V, VBB = +12V, VIN = +3.3 VDC, CL = 8 pF, TC = 60˚C.
DC Output Voltage
DC Voltage Gain
Per Channel, No Output Load
All Three Channels
VIN = 1.9V
(Notes 4, 5)
22 27 32
40 50 60
62 65 68
−12 −14 −16
tr Rise Time
tf Fall Time
10% to 90%, 40 VPP Output (1 MHz)
10% to 90%, 40 VPP Output (1 MHz)
40 VPP Output (1 MHz)
Note 1: “Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. They are not meant to imply that the devices
should be operated at these limits. The table of “Electrical Characteristics” specifies conditions of device operation.
Note 2: All voltages are measured with respect to GND, unless otherwise specified.
Note 3: Operating ratings indicate conditions for which the device is functional, but do not guarantee specific performance limits. For guaranteed specifications and
test conditions, see the Electrical Characteristics. The guaranteed specifications apply only for the test conditions listed. Some performance characteristics may
change when the device is not operated under the listed test conditions.
Note 4: Calculated value from voltage gain test on each channel.
Note 5: Linearity error is the variation in DC gain from VIN = 1.5V to VIN = 5V.
Note 6: Input from signal generator: tr, tf < 1 ns.
AC Test Circuit
FIGURE 2. Test Circuit (One Channel)
Figure 2 shows a typical test circuit for evaluation of the
LM2402. This circuit is designed for testing the LM2402 with
a FET probe. When calculating the total load capacitance,
the Tektronix P6201 FET probe with a 100:1 divider is speci-
fied to have 1.5 pF. The total board capacitance should be
Typical Performance Characteristics
FIGURE 3. VIN vs VOUT
FIGURE 6. Power Dissipation vs Frequency
FIGURE 4. Speed vs Temp.
FIGURE 7. Speed vs Offset
FIGURE 5. Rise/Fall Time
FIGURE 8. Bandwidth
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