OPA2381 Datasheet, PDF (1/19 Pages) Burr-Brown (TI) – Precision, Low Power, 18MHz Transimpedance Amplifier

OPA381
OPA2381
SBOS313B − AUGUST 2004 − REVISED NOVEMBER 2004
Precision, Low Power, 18MHz
Transimpedance Amplifier
FEATURES
D OVER 250kHz TRANSIMPEDANCE
BANDWIDTH
D DYNAMIC RANGE: 5 Decades
D EXCELLENT LONG-TERM STABILITY
D LOW VOLTAGE NOISE: 10nV/√Hz
D BIAS CURRENT: 3pA
D OFFSET VOLTAGE: 25µV (max)
D OFFSET DRIFT: 0.1µV/°C (max)
D GAIN BANDWIDTH: 18MHz
D QUIESCENT CURRENT: 800µA
D FAST OVERLOAD RECOVERY
D SUPPLY RANGE: 2.7V to 5.5V
D SINGLE AND DUAL VERSIONS
D MicroPACKAGE: DFN-8, MSOP-8
APPLICATIONS
D PRECISION I/V CONVERSION
D PHOTODIODE MONITORING
D OPTICAL AMPLIFIERS
D CAT-SCANNER FRONT-END
D PHOTO LAB EQUIPMENT
R_F
+5V
7
2
OPA381
VOUT
6 ^{(0V to 4.4V)}
Photodiode
C_DIODE
1MΩ
3
65pF
100kΩ
75pF
R_P
(Optional
Pulldown
Resistor)
− 5V
4
DESCRIPTION
The OPA381 family of transimpedance amplifiers provides
18MHz of Gain Bandwidth (GBW), with extremely high
precision, excellent long-term stability, and very low 1/f noise.
The OPA381 features an offset voltage of 25µV (max), offset
drift of 0.1µV/°C (max), and bias current of 3pA. The OPA381
far exceeds the offset, drift, and noise performance that
conventional JFET op amps provide.
The signal bandwidth of a transimpedance amplifier depends
largely on the GBW of the amplifier and the parasitic
capacitance of the photodiode, as well as the feedback
resistor. The 18MHz GBW of the OPA381 enables a trans-
impedance bandwidth of > 250kHz in most configurations.
The OPA381 is ideally suited for fast control loops for power
level measurement on an optical fiber.
As a result of the high precision and low-noise characteristics
of the OPA381, a dynamic range of 5 decades can be
achieved. This capability allows the measurement of signal
currents on the order of 10nA, and up to 1mA in a single I/V
conversion stage. In contrast to logarithmic amplifiers, the
OPA381 provides very wide bandwidth throughout the full
dynamic range. By using an external pulldown resistor to
–5V, the output voltage range can be extended to include 0V.
The OPA381 and OPA2381 are both available in MSOP-8
and DFN-8 (3mm x 3mm) packages. They are specified
from –40°C to +125°C.
OPA381 RELATED DEVICES
PRODUCT FEATURES
OPA380
90MHz GBW, 2.7V to 5.5V Supply
Transimpedance Amplifier
OPA132
16MHz GBW, Precision FET Op Amp ±15V
OPA300
150MHz GBW, Low-Noise, 2.7V to 5.5V Supply
OPA335
OPA350
OPA354
10µV VOS, Zero-Drift, 2.5V to 5V Supply
500µV VOS, 38MHz, 2.5V to 5V Supply
100MHz GBW CMOS, RRIO, 2.5V to 5V Supply
OPA355
200MHz GBW CMOS, 2.5V to 5V Supply
OPA656/7 230MHz, Precision FET, ±5V
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PRODUCTION DATA information is current as of publication date. Products
conform to specifications per the terms of Texas Instruments standard warranty.
Production processing does not necessarily include testing of all parameters.
Copyright  2004, Texas Instruments Incorporated
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