NSC LM2467TA Datasheet

LM2467
Monolithic Triple 7.5 ns CRT Driver

LM2467 Monolithic Triple 7.5 ns CRT Driver

October 2000

General Description

The LM2467 is an integrated high voltage CRT driver circuit
designed for use in color monitor applications. 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 −20 and can drive CRT
capacitive loads as well as resistive loads present in other
applications, limited only by the package’s power dissipation.

The IC is packaged in an industry standard 9-lead TO-220
molded plastic power package. See Thermal Considerations
section.

Schematic and Connection Diagrams

Features

n Higher gain to match LM126X CMOS preamplifiers
n 0V to 3.75V input range
n Stable with 0–20 pF capacitive loads and inductive

peaking networks

n Convenient TO-220 staggered lead package style
n Maintains standard LM243X Family pinout which is

designed for easy PCB layout

Applications

n 1024 x 768 displays up to 85 Hz refresh
n Pixel clock frequencies up to 95 MHz
n Monitors using video blanking

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Note: TabisatGND

Top View

Order Number LM2467T

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FIGURE 1. Simplified Schematic Diagram

(One Channel)

© 2000 National Semiconductor Corporation DS200078 www.national.com

Absolute Maximum Ratings (Notes 1, 3)

If Military/Aerospace specified devices are required,

LM2467

please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.

Supply Voltage (V
Bias Voltage (V
Input Voltage (V
Storage Temperature Range (T

) +90V

CC

) +16V

BB

) 0V to 4.5V

IN

) −65˚C to +150˚C

STG

Lead Temperature

<

(Soldering,

10 sec.) 300˚C

ESD Tolerance, Human Body Model 2 kV

Machine Model 250V

Operating Ranges (Note 2)

V

CC

V

BB

V

IN

V

OUT

+60V to +85V

+8V to +15V

+0V to +3.75V

+15V to +75V
Case Temperature −20˚C to +100˚C
Do not operate the part without a heat sink.

Electrical Characteristics

(See

Figure 2

Unless otherwise noted: VCC= +80V, VBB= +12V, CL= 8 pF, TC= 50˚C
DC Tests: V
AC Tests: Output = 40VPP(25V - 65V) at 1MHz

Symbol Parameter Conditions

I

CC

I

BB

V

OUT

A

V

∆A

V

LE Linearity Error (Notes 4, 5), No AC Input Signal 5 %
t

R

t

F

OS Overshoot (Note 6) 5 %

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur.
Note 2: 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 3: All voltages are measured with respect to GND, unless otherwise specified.
Note 4: Calculated value from Voltage Gain test on each channel.
Note 5: Linearity Error is the variation in dc gain from V
Note 6: Input from signal generator: t

for Test Circuit)

= 2.25VDC

IN

LM2467

Min Typical Max

Supply Current All Three Channels, No Input Signal,

No Output Load

30 mA

Bias Current All Three Channels 18 mA
DC Output Voltage No AC Input Signal, VIN= 1.25V 62 65 68 V
DC Voltage Gain No AC Input Signal −18 −20 −22
Gain Matching (Note 4), No AC Input Signal 1.0 dB

Rise Time (Note 6), 10% to 90% 7.5 ns
Fall Time (Note 6), 90% to 10% 8 ns

= 1.0V to VIN= 3.5V.

IN

r,tf

<

1 ns.

Units

DC

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AC Test Circuit

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Note: 8 pF load includes parasitic capacitance.

FIGURE 2. Test Circuit (One Channel)

Figure 2

environment without the use of an expensive FET probe. The two 2490Ω resistors form a 200:1 divider with the 50Ω resistor and
the oscilloscope. A test point is included for easy use of an oscilloscope probe.The compensation capacitor is used to
compensate the stray capacitance of the two 2490Ω resistors to achieve flat frequency response.

shows a typical test circuit for evaluation of the LM2467. This circuit is designed to allow testing of the LM2467 in a 50Ω

LM2467

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Typical Performance Characteristics (V

(25V−65V), Test Circuit -

LM2467

Figure 2

unless otherwise specified)

= +80 VDC,VBB= +12 VDC,CL= 8 pF, V

CC

OUT

=40V

PP

FIGURE 3. V

OUT

vs V

IN

FIGURE 4. Speed vs Temp.

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FIGURE 6. Power Dissipation vs Frequency

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FIGURE 7. Speed vs Offset

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FIGURE 5. LM2467 Pulse Response

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FIGURE 8. Speed vs Load Capacitance