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LT1169

Dual Low Noise,

Picoampere Bias Current,

JFET Input Op Amp

DESCRIPTIO

S

FEATURE

The LT1169 achieves a new standard of excellence in noise

performance for a dual JFET op amp. For the first time low

voltage noise (6nV/

√Hz) is simultaneously offered with

extremely low current noise (1fA/

√Hz), providing the low-

est total noise for high impedance transducer applications.

Unlike most JFET op amps, the very low input bias current

(5pA Typ) is maintained over the entire common mode

range which results in an extremely high input resistance

Ω). When combined with a very low input capaci-

tance (1.5pF) an extremely high input impedance results,

making the LT1169 the first choice for amplifying low level

signals from high impedance transducers. The low input

capacitance also assures high gain linearity when buffering

AC signals from high impedance transducers.

The LT1169 is unconditionally stable for gains of 1 or more,

even with 1000pF capacitive loads. Other key features are

vidual amplifier is 100% tested for voltage noise, slew rate

(4.2V/

µs), and gain-bandwidth product (5.3MHz).

The LT1169 is offered in the S8 and N8 packages.

A full set of matching specifications are provided for

precision instrumentation amplifier front ends. Specifica-

tions at

±5V supply operation are also provided. For an

even lower voltage noise please see the LT1113 data sheet.

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Input Bias Current, Warmed Up: 20pA Max

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100% Tested Low Voltage Noise: 8nV/

√Hz Max

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S8 and N8 Package Standard Pinout

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Very Low Input Capacitance: 1.5pF

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Voltage Gain: 1.2 Million Min

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Offset Voltage: 2mV Max

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Ω

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Gain-Bandwidth Product: 5.3MHz Typ

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Guaranteed Specifications with

±5V Supplies

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Guaranteed Matching Specifications

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APPLICATI

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Photocurrent Amplifiers

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Hydrophone Amplifiers

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High Sensitivity Piezoelectric Accelerometers

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Low Voltage and Current Noise Instrumentation

Amplifier Front Ends

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Two and Three Op Amp Instrumentation Amplifiers

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Active Filters

APPLICATI

TYPICAL

, LTC and LT are registered trademarks of Linear Technology Corporation.

Low Noise Light Sensor with DC Servo

8

+V

–V

4

LT1169 • TA01

R1

1M

C1

2pF

7

5

6

1/2 LT1169

R2C2 > C1R1

330mV/

µWATT FOR 633nm WAVE LENGTH

R5

10k

D2

1N914

V–

R4

1k

D1

1N914

R3

1k

1

3

2

1/2 LT1169

C2

0.022

µF

HAMAMATSU

S1336-5BK

(908) 231-0960

R2

100k

2N3904

SOURCE RESISTANCE (

Ω)

10k

1k

100

10

1

100

10k

100k

1M

1k

10M

LT1169 • TA02

100M 1G

–

+

SOURCE

RESISTANCE

ONLY

1kHz Output Voltage Noise

Density vs Source Resistance