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LT1122

Fast Settling, JFET Input

Operational Amplifier

s

100% Tested Settling Time

340ns Typ

to 1mV at Sum Node, 10V Step

540ns Max

Tested with Fixed Feedback Capacitor

s

Slew Rate

60V/

µs Min

s

Gain Bandwidth Product

14MHz

s

Power Bandwidth (20Vp-p)

1.2 MHz

s

Unity Gain Stable; Phase Margin

60

°

s

Input Offset Voltage

600

µV Max

s

Input Bias Current

25

°C

75pA Max

70

°C

600pA Max

s

Input Offset Current

25

°C

40pA Max

70

°C

150pA Max

s

Low Distortion

DESCRIPTIO

S

FEATURE

The LT1122 JFET input operational amplifier combines

high speed and precision performance.

A unique poly-gate JFET process minimizes gate series

resistance and gate-to-drain capacitance, facilitating wide

bandwidth performance, without degrading JFET transis-

tor matching.

It slews at 80V/

µs and settles in 340ns. The LT1122 is

internally compensated to be unity gain stable, yet it has a

bandwidth of 14MHz at a supply current of only 7mA. Its

speed makes the LT1122 an ideal choice for fast settling

12-bit data conversion and acquisition systems.

The LT1122 offset voltage of 120

µV, and voltage gain of

500,000 also support the 12-bit accurate applications.

The input bias current of 10pA and offset current of 4pA

combined with its speed allow the LT1122 to be used in

such applications as high speed sample and hold amplifi-

ers, peak detectors, and integrators.

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Fast 12-Bit D/A Output Amplifiers

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High Speed Buffers

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Fast Sample and Hold Amplifiers

s

High Speed Integrators

s

Voltage to Frequency Converters

s

Active Filters

s

Log Amplifiers

s

Peak Detectors

12-Bit Voltage Output D/A Converter

Large-Signal Response

200ns/DIV

AV = –1

1122 TA07

S

APPLICATI

APPLICATI

TYPICAL

0mA TO 2mA

OR 4mA

+

2

3

6

Cf

V

0V TO 10V

OUT

12-BIT CURRENT OUTPUT D/A CONVERTER

C = 5pF TO 17pF

(DEPENDING ON D/A CONVERTER USED)

+

–

f

LT1122

LT1122•TA01