NSC LM2407T Datasheet

LM2407
Monolithic Triple 7.5 nS CRT Driver

LM2407 Monolithic Triple 7.5 nS CRT Driver

August 1999

General Description

The LM2407 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 drivethe 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 present in other ap­plications, limited only by the package’s power dissipation.

The IC is packaged in an industry standard 11-lead TO-220
molded plastic power package. See thermal considerations
on page 6.

Schematic and Connection Diagrams

Features

n Low power dissipation
n Well matched with LM1279 video preamp
n 0V to 5V input range
n Stable with 0 pF–20 pF capacitive loads and inductive

peaking networks

n Convenient TO-220 staggered lead package style
n Standard LM240X 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 100 MHz
n Monitors using video blanking

Note: TabisatGND

Top View

Order Number LM2407T

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FIGURE 1. Simplified Schematic Diagram

(One Channel)

© 1999 National Semiconductor Corporation DS100093 www.national.com

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Absolute Maximum Ratings (Notes 1, 3)

If Military/Aerospace specified devices are required,
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
Lead Temperature

(Soldering,

) +90V

CC

) +16V

BB

) −0.5V to V

IN

<

10 sec.) 300˚C

) −65˚C to +150˚C

STG

BIAS

+0.5V

Machine Model 300V

Operating Range(Note 2)

V

CC

V

BB

V

IN

V

OUT

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

+60V to +85V

+8V to +15V

+0V to +5V

+15V to +75V

ESD Tolerance, Human Body Model 2 kV

Electrical Characteristics

(See

Figure 2

Unless otherwise noted: V

for Test Circuit)

Symbol Parameter Condition

I
I
V
A
∆A

CC
BB

OUT
V

Supply Current Per Channel, No Output Load 11.5 mA
Bias Current All Three Channels 11 mA
DC Output Voltage No AC Input Signal, VIN= 1.2V 62 65 68 V
DC Voltage Gain No AC Input Signal −13.3 −13.9 −14.5
Gain Matching (Note 4), No AC Input Signal 1.0 dB

V

LE Linearity Error (Notes 4, 5), No AC Input Signal 8
t

R

t

F

Rise Time 10%to 90
Fall Time 90%to 10

OS Overshoot Rising Edge 8

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

= +80V, VBB= +12V, VIN= +2.7 VDC,CL= 8 pF, Output = 40 VPPat 1 MHz, TC= 50˚C.

CC

LM2407

Min Typical Max

%
%

7.5 nS

7.5 nS

Falling Edge 2

= 1.0V to VIN= 4.5V.

1 nS.

IN

r,tf

<

Units

DC

%

%

AC Test Circuit

Note: 8 pF load includes parasitic capacitance.

FIGURE 2. Test Circuit (One Channel)

Figure 2

shows a typical test circuit for evaluation of the LM2407. This circuit is designed to allow testing of the LM2407 in a 50Ω
environment without the use of an expensive FET probe. The 4950Ω resistor at the output forms a 100:1 voltage divider when
connected to a 50Ω load.

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AC Test Circuit (Continued)

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. LM2407 Pulse Response

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FIGURE 8. Speed vs Load Capacitance

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