LT1169 Datasheet, PDF (1/12 Pages) Linear Technology – Dual Low Noise, Picoampere Bias Current, JFET Input Op Amp

FEATURES
s _{Input Bias Current, Warmed Up: 20pA Max}
s _{100% Tested Low Voltage Noise: 8nV/√Hz Max}
s _{S8 and N8 Package Standard Pinout}
s _{Very Low Input Capacitance: 1.5pF}
s _{Voltage Gain: 1.2 Million Min}
s _{Offset Voltage: 2mV Max}
s _{Input Resistance: 10}¹³_Ω
s _{Gain-Bandwidth Product: 5.3MHz Typ}
s _{Guaranteed Specifications with ±5V Supplies}
s _{Guaranteed Matching Specifications}
APPLICATI S
s _{Photocurrent Amplifiers}
s _{Hydrophone Amplifiers}
s _{High Sensitivity Piezoelectric Accelerometers}
s _{Low Voltage and Current Noise Instrumentation}
Amplifier Front Ends
s _{Two and Three Op Amp Instrumentation Amplifiers}
s _{Active Filters}
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATI
Low Noise Light Sensor with DC Servo
C1
2pF
D2
1N914
2–
1
1/2 LT1169
3+
R1
1M
C2
0.022µF
V_OUT
C_D
2N3904
HAMAMATSU
R5
S1336-5BK
10k
[phone]
V–
+V
R2
D1
1N914
R3
1k
7
8
6
100k
1/2 LT1169
5
R4
1k
4
R2C2 > C1R1
–V
C_D = PARASITIC PHOTODIODE CAPACITANCE
V_OUT = 100mV/µWATT FOR 200nm WAVE LENGTH
330mV/µWATT FOR 633nm WAVE LENGTH
LT1169 • TA01
LT1169
Dual Low Noise,
Picoampere Bias Current,
JFET Input Op Amp
DESCRIPTIO
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
(10¹³â„¦). 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
0.6mV V_OS and a voltage gain over 4 million. Each indi-
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.
1kHz Output Voltage Noise
Density vs Source Resistance
10k
–
1k
+
V_N
R_SOURCE
100
10 VN
SOURCE
RESISTANCE
T_A = 25°C
ONLY
V_S = ±15V
1
100 1k 10k 100k 1M 10M 100M 1G
SOURCE RESISTANCE (Ω)
V_N = √(V_{OP AMP})² + 4kTR_S + 2qI_BR_S2
LT1169 • TA02
1