OP-160_15 Datasheet, PDF (22/24 Pages) Analog Devices – High-Speed, Current Feedback Operational Amplifier

ANALOGDEVICES fAX-ON-DEMAND HOTLINE _{- Page 23}
OP-160
OP-160 SPICE MACRO-MODEL
Figures 30 and 31 showtheSPICE macro-modelfortheOP-160
high-speed. current feedback operational amplifier. This model
was tested with, and is compatible with PSpice* and HSpice".
The schematic and net-list are included here so that the model
can easily be used. This model uses a unique current feedback
topology to accurately model both the AC and DC characteris-
tics of theOP-160. tn addition, this modelcan accommodate any
number of poles and zeros to further shape the AC response.
rising and falling slew rates can be adjusted by varying the
values of V1 and V2 in the model. Slew rates for various gains
can be determined from Figures 6a and 6b.
V1 + O.6V
Rising Slew Rate = (1k!l){5pF)
V2 + O.6V
Falling Slew Rate = (1k!l){SpF)
The OP-160 SPICE macro-model uses four BJT transistors to
To keep the OP-160 model as simple as possible and thus save
create the input buffer as in the actual device. However, the rest
computer and development time, not all features of the op amp
of the model contains only ideal linear elements and ideal diodes
were modelled as listed below:
to model the OP-160's behavior. Using only four transistors
reduces simulation time and simplifies model development. II
simulates important DC parameters such as Vas' la' CMR, Va
- _{and ISY'AC parameters such as slew rate, open-loop transim-}
- _{pedance and phase response and CMR changes with fre-}
quency are also simulated by the model. In addition, the model
includes the change in input bias current with varying common-
mode and power supply voltages. Both output swing and supply
O_{current are accurately modelled.}
B One aspect of theOP-160's behavior is that slew rate varies with
closed-loop gain. Slew rate of the basic model is set to the typi-
SOLETE _{cal values for the OP-160 in a gain of +1. For other gains, the}
-PSR
- Crosstalk
- No Hmits on power supply voltages
Maximum input voltage range
Temperature effects (i.e.. model parameters are assumed
at 25°C)
-Input noise voltage and current sources
- Parameter variations for Monte Carlo analysis (i.e., all
parameters are typical only)
These parameters are considered second-order effects and are
not considered necessary for circuit simulation under normal
operating conditions. However. users can easily add these func-
tions as needed.
... PSpiceis a registered trademarK 01 MlcroSim Corporation.
HSPICE is a tradename 01 Mela-Software. Inc.
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