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Component Properties

How to configure component parameters and what each field means.

Opening the properties panel

Click any component on the canvas to select it. The properties panel opens on the right side of the editor and shows all configurable fields for that component type.

Changes take effect immediately — the simulation uses the updated values the next time it runs.

Common fields

Every component has a Name field (free text label displayed on the canvas) and type-specific fields described below.


Resistor

FieldUnitDescription
ResistanceΩResistance value (e.g., 10k, 4.7k, 100)
Power RatingWMaximum power dissipation before failure
ShapeCylinder or rectangle (affects thermal model)
Length / DiametermmPhysical dimensions for thermal calculation
MaterialCarbon film, metal film, wirewound, etc.
Temp Coefficientppm/°CHow resistance changes with temperature
Max Operating Temp°CJunction temperature limit

Rheostat (variable resistor)

FieldUnitDescription
Max ResistanceΩResistance at full turn
Min ResistanceΩResistance at zero turn
TaperLinear or logarithmic response curve

Capacitor (polarized)

FieldUnitDescription
CapacitanceFValue (e.g., , 100n)
Max VoltageVVoltage rating — exceeded voltage causes failure
ESRΩEquivalent series resistance
Leakage CurrentACurrent that leaks through the dielectric
Max Operating Temp°CTemperature limit

Capacitor (non-polarized)

Same fields as polarized capacitor except no polarity constraint.

Inductor

FieldUnitDescription
InductanceHValue (e.g., 100µ, 10m)
Tolerance%Manufacturing tolerance
DCRΩDC winding resistance
Max CurrentASaturation current

Diode

FieldUnitDescription
Saturation CurrentAReverse saturation current (Is)
Ideality FactorDiode quality factor (1.0–2.0)
Series ResistanceΩInternal series resistance
Reverse BreakdownVReverse voltage limit
Max Forward CurrentAPeak forward current
Max PowerWMaximum power dissipation
Thermal Resistance°C/WJunction-to-ambient thermal resistance

LED

FieldUnitDescription
ColorRed, green, blue, white, UV, etc. (sets forward voltage)
Forward VoltageVTypical Vf at rated current
Rated CurrentACurrent at which Vf is measured
Max Reverse VoltageVMaximum reverse voltage
Max Forward CurrentAAbsolute maximum current
Thermal Resistance°C/WJunction-to-ambient

NPN / PNP Transistor

FieldUnitDescription
Beta (hFE)Current gain
VbeVBase-emitter junction voltage
Max VbeVMaximum base-emitter voltage
Max VceVMaximum collector-emitter voltage
Max IcAMaximum collector current
Max PowerWMaximum power dissipation
Transition FrequencyHzUnity-gain bandwidth
Max Junction Temp°CTemperature limit

N-Channel / P-Channel MOSFET

FieldUnitDescription
Gate Threshold VoltageVVgs(th) — gate voltage to turn on
Max Drain-Source VoltageVVds breakdown
Max Drain CurrentAContinuous drain current
Rds(on)ΩOn-state drain-source resistance
Max PowerWMaximum power dissipation
PackagePhysical package (TO-220, SOT-23, etc.)

Battery

FieldUnitDescription
TypeLi-Ion, Li-Poly, Alkaline, NiMH, NiCd, Lead-Acid, Zinc-Carbon
Nominal VoltageVOutput voltage
CapacitymAhStored charge
Internal ResistanceΩSeries resistance (affects voltage under load)
Charge Level%Current state of charge (100% = full)

Sine Generator

FieldUnitDescription
Output FrequencyHzSignal frequency (e.g., 1k, 60)
Output VoltageVPeak amplitude
Output ImpedanceΩSource impedance
THD%Total harmonic distortion

Square Generator

FieldUnitDescription
FrequencyHzClock frequency
High VoltageVLogic-high level
Low VoltageVLogic-low level
Duty Cycle%High-time fraction (50% = symmetric)
Output ImpedanceΩSource impedance

Switches (Push Button, Toggle, SPDT, Multi)

FieldUnitDescription
Max VoltageVRated operating voltage
Max CurrentAMaximum switching current
Contact ResistanceΩClosed-state resistance
LifetimecyclesNumber of operations before wear

Relay

FieldUnitDescription
Coil VoltageVVoltage to energize the coil
Coil CurrentmACurrent drawn by coil when energized
Max Contact VoltageVVoltage rating for the switched contacts
Max Contact CurrentACurrent rating for the switched contacts

Transformer

FieldUnitDescription
Turns RatioPrimary:secondary winding ratio (e.g., 10:1)
Primary VoltageVExpected primary-side voltage
Secondary VoltageVOutput voltage
Power RatingVAMaximum apparent power
Core TypeIron, ferrite, air

Ammeter

FieldUnitDescription
Internal ResistanceΩSeries resistance introduced by the meter
Max CurrentAFull-scale reading
Accuracy%Measurement error
ResolutionASmallest readable change

Voltmeter

FieldUnitDescription
Internal ResistanceShunt resistance (high = less loading)
Max VoltageVFull-scale reading
Accuracy%Measurement error
ResolutionVSmallest readable change

Bulb

FieldUnitDescription
VoltageVRated operating voltage
PowerWPower at rated voltage

Optocoupler

FieldUnitDescription
NamePart number label