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dc2551af

DEMO MANUAL DC2551A

Description

LT1997

Configurable Precision Amplifier

Demonstration Circuit 2551A is a Configurable Precision

Amplifier featuring the LT®1997.

The DC2551A-A supports the LT1997-3 version.

This demo board provides a rapid evaluation tool with

jumpers providing the typical interconnection options that

facilitate setting the pin-strapped internal gain configura-

tion. The LT1997 is unusual in that it may be powered

from a low voltage (down to 3.3V) while it accepts signals

well outside the supply range. This device also supports

L

, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear

Technology Corporation. All other trademarks are the property of their respective owners.

performance summary

operating principles

particularly high supply voltages, up to 50V. Connection

points are provided to wire the amplifier in other configu-

rations besides those possible with the jumpers alone.

The key performance characteristics of the LT1997 and

DC2551A are shown in the Performance Summary below.

Design files for this circuit board are available at

http://www.linear.com/demo/DC2551A

SYMBOL

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

Input Range

Thermally Limited to Short-Term

–160

160

V

Other Inputs

–0.3

80

V

Amplifier Supply Range (Total If Split Supplies)

3.3

5…30

50

V

Output Signal

V

Output Current Range

±10

±25

mA

Supply Current

330

525

µA

BW

Small Signal –3dB Bandwidth

300

1100

kHz

The LT1997 is an op amp that includes integrated preci-

sion resistors for providing many useful high accuracy

functions with minimal external components. The default

configuration of the demo circuit is a difference amplifier

structure with gain set to minimum and the output refer-

enced to mid-supply. Refer to the LT1997 data sheet for

tabulations of various practical circuit configurations that

can be implemented, many of which are easily created by

jumperrelocationonthedemoboard.Largeviasandsome

spare pads are also provided so that other more special-

ized configurations can be evaluated, such as AC-coupled

gain blocks or summing amplifiers. The demo circuit also

provides connector footprints for user-furnished BNC

connectors if cable connectivity is desired.