Comparator

The behavioral model of the comparator integrated circuit.

blockType: AcausalElectricPowerSystems.IntegratedCircuits.Comparator

Path in the library:

/Physical Modeling/Electrical/Integrated Circuits/Comparator

Description

Block Comparator It is an abstract behavioral model of a comparator integrated circuit. It does not model the internal implementation at the transistor level. Therefore, the block is executed quickly during the simulation, while maintaining the correct behavior of the inputs and outputs. The block models differential inputs from the point of view of electrical engineering as having infinite resistance and finite or zero capacitance.

The block simulates a logical output signal as a voltage source controlling a series-connected resistor and a capacitor connected to ground. The output contact is connected to the junction of the resistor and capacitor. If the input voltage difference exceeds the threshold input voltage, the output signal is equal to the value of the parameter High level output voltage ( ). Otherwise, the output signal is equal to the value of the parameter Low level output voltage ( ).

comparator 1

The output model is shown in the following figure.

comparator 2

Assumptions and limitations

The simulation of the output signal in the form of a controlled voltage source corresponds to the output push-pull cascade (totem-pole) or cascade type «push pull» (push-pull). For modeling an open collector device:

Connect the output pin to the base of the unit NPN Bipolar Transistor or PNP Bipolar Transistor.
Set for the parameter Output resistance the appropriate value.

Ports

Conserving

# + — non-inverting input
electricity

Details

A non-directional port connected to a non-inverting comparator input.

Program usage name

p

# − — inverting input
electricity

Details

A non-directional port connected to the inverting input of the comparator.

Program usage name

n

# OUT — Output port
electricity

Details

An undirected port connected to the comparator output.

Program usage name

output_pin

Parameters

Outputs

# Propagation delay — propagation delay
s | ns | us | ms | min | hr | d

Details

Set this value taking into account the delays in signal propagation from high to low and from low to high.

Units	`s` \| `ns` \| `us` \| `ms` \| `min` \| `hr` \| `d`
Default value	`0.0 s`
Program usage name	`delay`
Evaluatable	Yes

# Output resistance — output resistance
Ohm | mOhm | kOhm | MOhm | GOhm

Details

The ratio of the output voltage drop to the output current. Set this parameter to , where — reduced output high voltage at output current .

Units	`Ohm` \| `mOhm` \| `kOhm` \| `MOhm` \| `GOhm`
Default value	`50.0 Ohm`
Program usage name	`R_output`
Evaluatable	Yes

# Low level output voltage — low-level output voltage
V | uV | mV | kV | MV

Details

Steady-state output voltage when the voltage difference at the inputs is less than or equal to the threshold voltage, and the output current is zero.

Units	`V` \| `uV` \| `mV` \| `kV` \| `MV`
Default value	`0.0 V`
Program usage name	`V_OL`
Evaluatable	Yes

# High level output voltage — high-level output voltage
V | uV | mV | kV | MV

Details

Steady-state output voltage when the voltage difference at the inputs exceeds the threshold voltage and the output current is zero.

Units	`V` \| `uV` \| `mV` \| `kV` \| `MV`
Default value	`5.0 V`
Program usage name	`V_OH`
Evaluatable	Yes

Inputs

# Average input capacitance — average input capacity
F | pF | nF | uF | mF

Details

Usually, the capacity value can be found in the manufacturer’s technical description. Setting this value to zero can reduce the simulation time.

Units	`F` \| `pF` \| `nF` \| `uF` \| `mF`
Default value	`0.0 pF`
Program usage name	`C_input`
Evaluatable	Yes

# Input offset voltage — input bias voltage
V | uV | mV | kV | MV

Details

The voltage that must exceed the input voltage difference in order for the comparator to produce a logical output signal 1.

Units	`V` \| `uV` \| `mV` \| `kV` \| `MV`
Default value	`5.0 mV`
Program usage name	`V_offset`
Evaluatable	Yes