NSC LM2480NA Datasheet

LM2480
80V Triple Bias Clamp

General Description

The LM2480 driver is an Integrated 80V triple bias clamp
circuit for DC recovery of each of the AC coupled outputs of
a CRT driver. It is well matched with the DAC outputs of the
LM126X family of pre-amplifiers. Each amplifier has its gain
internally set to -18. The IC is packaged in an industry
standard 8 lead molded DIP package.

Features

n Wide range integrated triple bias clamp
n High input impedance

Block Diagrams Package Pinout

n Single supply operation
n Matched to the LM126X family of preamplifiers

Recommended Applications

n CRT monitors requiring DC restoration at the cathodes

LM2480 80V Triple Bias Clamp

October 2001

20008301

FIGURE 1. Simplified Schematic (One Channel)

20008302

FIGURE 2. LM2480 Package Pinout

Order Number LM2480NA

NS Package Number: N08E

© 2001 National Semiconductor Corporation DS200083 www.national.com

Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,

LM2480

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

Supply Voltage, V
Input Voltage, V
Storage Temperature Range, T
Lead Temperature (Soldering,

<

10sec.) 300˚C

CC

IN

STG

-65˚C to +150˚C

+90V

0V to 5V

Machine Model 200V
Human Body Model 2KV

Limits of Operating Ranges (Note 3)

V

CC

V

OUT

Ambient Temperature Range, T

A

ESD Tolerance

DC CLAMP ELECTRICAL CHARACTERISTICS TARGETS AND LIMIT

Unless otherwise noted: VCC= +80V, VIN= 2.25VDC,TA= 25˚C.

Symbol Spec Parameter Conditions Min Typ Max Units

I

CC

V

OUT

V

OUT-Range

V

OUTSAT

A

V

Supply Current All channels 2.1 3.5 mA
DC Output Voltage 42 46 50 V
Output Voltage Range VINRange = 1.0V - 4.0V 53 V
Max Saturation Limit VIN= 4.0V 16 V

DC Voltage Gain -16 -18 -20
LE Linearity Error See Note 1 5 %
R

IN

Note 1: Linearity Error is the variation in DC gain from VIN= 1.0V to VIN= 4.0V.
Note 2: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur.
Note 3: Operating Ratingsindicateconditions for which the device is functional, but do not guarantee specific performance limits. For guaranteed specificationsand

the 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: All voltages are measured with respect to GND, unless otherwise specified.

Input Resistance 34K Ω

70V to 85V
10V to V

CC

0 to 70˚C

DC

DC

Test Circuit

Figure 3

measurements at the output.

shows the test circuit for evaluation of the LM2480 Clamp Amplifier. A high impedance VM (>100MΩ) is used for DC

20008303

FIGURE 3. Test Circuit (One Channel)

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