Exponential Current Source

Exponential pulsed current source.

blockType: AcausalElectricPowerSystems.SPICE.Sources.ExponentialCurrentSource

Path in the library:

/Physical Modeling/Electrical/SPICE/Sources/Exponential Current Source

Description

The Exponential Current Source unit is a current source whose output current value is an exponential pulse as a function of time and is independent of the voltage at the source terminals.

The following equations describe the current through the source as a function of time:

where

- corresponds to the Initial value, I1;
- corresponds to the Pulse value, I2;
- corresponds to the value of the parameter Rise delay time, TDR;
- corresponds to the value of the parameter Rise time, TR;
- corresponds to the value of the parameter Fall delay time, TDF;
- corresponds to the value of the parameter Fall time, TF.

To prevent problems in numerical modelling, a small internal conductance is used in the block. The conductance connects the + and - terminals of the device and has a conductance with the value GMIN:

By default, the value of GMIN is 1e-12 1/ohm.

Ports

Conserving

# + — positive terminal
scalar

Details

An electrical port connected to the positive terminal of a DC source.

Program usage name

p

# - — negative terminal
scalar

Details

An electrical port connected to the negative terminal of a DC source.

Program usage name

n

Parameters

# Initial value, I1 — initial value of the output current
A | pA | nA | uA | mA | kA | MA

Details

The value of the output current at zero time.

Units	`A` \| `pA` \| `nA` \| `uA` \| `mA` \| `kA` \| `MA`
Default value	`0.0 A`
Program usage name	`I1`
Evaluatable	Yes

# Pulse value, I2 — asymptotic value of the output current
A | pA | nA | uA | mA | kA | MA

Details

The asymptotic value of the output current when the output is high.

Units	`A` \| `pA` \| `nA` \| `uA` \| `mA` \| `kA` \| `MA`
Default value	`0.0 A`
Program usage name	`I2`
Evaluatable	Yes

# Rise delay time, TDR — delay time of exponent rise
s | ns | us | ms | min | hr | d

Details

The delay time of the exponent rise.

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

# Rise time, TR — exponent rise time
s | ns | us | ms | min | hr | d

Details

The time it takes for the output current to change from the value of Initial Value, I1 to the value of Pulse Value, I2.

Units	`s` \| `ns` \| `us` \| `ms` \| `min` \| `hr` \| `d`
Default value	`1e-9 s`
Program usage name	`TR`
Evaluatable	Yes

# Fall delay time, TDF — exponent decay delay time
s | ns | us | ms | min | hr | d

Details

The delay time of the exponent decay.

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

# Fall time, TF — exponent decline time
s | ns | us | ms | min | hr | d

Details

The time it takes for the output current to change from Pulse value, I2 to Initial value, I1.

Units	`s` \| `ns` \| `us` \| `ms` \| `min` \| `hr` \| `d`
Default value	`1e-9 s`
Program usage name	`TF`
Evaluatable	Yes

# Include parallel conductance, GMIN — enabling parallel conduction

Details

Switching on the parallel conductivity of the current source.

By default, the value of GMIN is `1e-12 1/Ohm'.

Default value	`true (switched on)`
Program usage name	`g_min_parameterization`
Evaluatable	No