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opamp

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opamp

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Iconic Diagrams\Electric\Components

Implementations

Default

Universal

Use

Domains: Continuous. Size: 1-D. Kind: Iconic Diagrams (Electric).

Description - Default

This model represents an ideal operational amplifier. The input resistance is infinite and the output resistance is zero. The port p_in of the OpAmp model has separate high and low terminals:

 

p_in.u = p_in_high.u - p_in_low.u;

p_in_high.i = p_in_low.i = p_in.i = 0;

p_out.u = A*p_in.u;

Interface - Default

Ports

Description

p_in_high, P_in_low

p_out

Both terminals of the input port p_in (Electric).

Output port (Electric).

Causality

 

fixed current out p_in

fixed voltage out p_out

 

Parameters

 

A

Amplification []

Description - Universal

This model represents an operational amplifier with a first order decreasing voltage amplification.

 

OpAmpbode

The amplification is parameterized by a DC-gain (A) and a cut-off frequency (f). This yields a unity gain frequency of:

 

unity gain frequency = A*f;

 

The gain is limited to yield an output that is between the positive (VDD) and negative (VEE) supply voltage.

OpAmpgain

The input resistance is infinite and the output resistance is equal to the parameter R. The port p_in of the OpAmp model has separate high and low terminals:

 

p_in.u = p_in_high.u - p_in_low.u

p_in_high.i = p_in_low.i = p_in.i = 0;

p_out.u = Adiff*p_in.u - R*p_out.u;

 

where Adiff is a dynamic gain according to the bode and gain plot.

Interface - Universal

Ports

Description

p_in_high, P_in_low

p_out

Both terminals of the input port p_in (Electric).

Output port (Electric).

Causality

 

fixed current out p_in

preferred voltage out p_out

 

Parameters

 

A

f

VDD

VEE

R

DC gain or DC Amplification

Cut-off frequency [Hz]

Positive supply voltage [V], choose VDD > VEE!

Negative supply voltage [V], choose VDD > VEE!

Output impedance [Ohm]