Data Sheet

ADA4077-1/ADA4077-2/ADA4077-4

THEORY OF OPERATION

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Rev. F | 21 of 25

The ADA4077-1/ADA4077-2/ADA4077-4 are the sixth generation of

the Analog Devices, Inc., industry-standard OP07 amplifier family.

The ADA4077-1/ADA4077-2/ADA4077-4 are high precision, low

noise operational amplifiers with a combination of extremely low off-

set 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 high voltage amplifiers with superi-

or performance to the OP07/OP77/OP177/OP1177 in tiny, 8-lead

SOIC and 8-lead MSOP packages (ADA4077-1 and ADA4077-2)

and 14-lead TSSOP and 14-lead SOIC packages (ADA4077-4).

Despite their small size, the ADA4077-1/ADA4077-2/ADA4077-4

offer numerous improvements, including low wideband noise, wide

bandwidth, lower offset and offset drift, lower input bias current, and

complete freedom from phase inversion.

The ADA4077-1/ADA4077-2/ADA4077-4 have an operating tem-

perature range of −40°C to +125°C with an MSL1 rating, which is

as wide as any similar device in a plastic surface-mount package.

This MSL1 rating is increasingly important as printed circuit board

(PCB) and overall system sizes continue to shrink, causing internal

system temperatures to rise.

In the ADA4077-1/ADA4077-2/ADA4077-4, the power consumption

is reduced by a factor of four compared to the OP177, and the

bandwidth and slew rate are both increased by a factor of six. The

low power dissipation and very stable performance vs. temperature

also reduce warmup drift errors to insignificant levels.

Inputs are protected internally from overvoltage conditions refer-

enced to either supply rail. Like any high performance amplifier,

maximum performance is achieved by following appropriate circuit

and PCB guidelines.