Datasheet

ADA4077-2 Data Sheet
Rev. 0 | Page 16 of 20
THEORY OF OPERATION
The ADA4077-2 is the sixth generation of the Analog Devices, Inc.,
industry-standard OP07 amplifier family. The ADA4077-2 is a
high precision, low noise operational amplifier with a combination
of extremely low offset voltage and very low input bias currents.
Unlike JFET amplifiers, the low bias and offset currents are
relatively insensitive to ambient temperatures, even up to 125°C.
The Analog Devices proprietary process technology and linear
design expertise have produced a high voltage amplifier with
superior performance to the OP07, OP77, OP177, and OP1177
in tiny, 8-lead SOIC and 8-lead MSOP packages. Despite its
small size, the ADA4077-2 offers numerous improvements,
including low wideband noise, wide bandwidth, lower offset
and offset drift, lower input bias current, and complete freedom
from phase inversion.
The ADA4077-2 has a specified operating temperature range of
−40°C to +125°C with a MSL1 rating, which is as wide as any
similar device in a plastic surface-mount package. This is
increasingly important as PCB and overall system sizes
continue to shrink, causing internal system temperatures to rise.
In the ADA4077-2, power consumption is reduced by a factor
of four from the OP177, and bandwidth and slew rate have both
increased by a factor of six. The low power dissipation and very
stable performance vs. temperature also act to reduce warm-up
drift errors to insignificant levels.
Inputs are protected internally from overvoltage conditions
referenced to either supply rail. Like any high performance
amplifier, maximum performance is achieved by following
appropriate circuit and PCB guidelines.