FEATURES
> 1MHz TRANSIMPEDANCE BANDWIDTH
EXCELLENT LONG-TERM VOS STABILITY
BIAS CURRENT: 50pA (max)
OFFSET VOLTAGE: 25μV (max)
DYNAMIC RANGE: 4 to 5 Decades
DRIFT: 0.1μV/°C (max)
GAIN BANDWIDTH: 90MHz
QUIESCENT CURRENT: 7.5mA
SUPPLY RANGE: 2.7V to 5.5V
SINGLE AND DUAL VERSIONS
MicroSize PACKAGE: MSOP-8

APPLICATIONS
PHOTODIODE MONITORING
PRECISION I/V CONVERSION
OPTICAL AMPLIFIERS
CAT-SCANNER FRONT-END

DESCRIPTION
The OPA380 family of transimpedance amplifiers provides
high-speed (90MHz Gain Bandwidth [GBW]) operation, with
extremely high precision, excellent long-term stability, and
very low 1/f noise. It is ideally suited for high-speed
photodiode applications. The OPA380 features an offset
voltage of 25μV, offset drift of 0.1μV/°C, and bias current of
50pA. The OPA380 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 90MHz GBW of the OPA380 enables a transimpedance
bandwidth of > 1MHz in most configurations. The
OPA380 is ideally suited for fast control loops for power level
on an optical fiber.
As a result of the high precision and low-noise characteristics
of the OPA380, a dynamic range of 4 to 5 decades can be
achieved. For example, this capability allows the
measurement of signal currents on the order of 1nA, and up
to 100μA in a single I/V conversion stage. In contrast to
logarithmic amplifiers, the OPA380 provides very wide
bandwidth throughout the full dynamic range. By using an
external pull-down resistor to –5V, the output voltage range
can be extended to include 0V.
The OPA380 (single) is available in MSOP-8 and SO-8
packages. The OPA2380 (dual) is available in the
miniature MSOP-8 package. They are specified from
–40°C to +125°C.