Ixxxxxxx

Independent Current Source: This device is translated as either an I_Source (ADS Netlist) or an ItUserDef (ADS Schematic).

Example SPICE Command Line:

i1 1 2 DC 6
i2 2 3 AC 1 90
i3 3 0 PULSE(-1 1 2NS 2NS 2NS 50NS 100NS)
i4 3 0 SIN(0 1 100MEG 1NS 1E10)
i5 3 0 EXP(-4 -1 2NS 30NS 60NS 40NS)
i6 7 5 PWL(0 -7 10NS -7 11NS -3 17NS -3 18NS -7 50NS -7)
i7 12 0 SFFM(0 1M 20K 5 1K)

SPICE dialect and netlist syntax:

Spice2/3:

i id n+ n- [[ dc ] dcval ] [ ac [ mag [ phase ]]] [ tranfunc ]

PSpice:

i id n+ n- [[ dc ] dcval ] [ ac [ mag [ phase ]]] [ tranfunc ]

HSpice:

i id n+ n- [[ dc ] dcval ] [ ac [ mag [ phase ]]] [ tranfunc ]

ADS Netlist Syntax:

I_Source:i*id n+ n- *Idc=*dcval *lac=polar(mag,phase) *I_Tran=*tranfunc

ADS Schematic Symbol:

Instance Parameters:

iid = GaAsFET element name
n+ = Positive node
n- = Negative node
dcval = The dc current
mag, phase = The magnitude and phase of the ac current.
tranfunc = Transient Source Functions. There are several built in ADS functions that mimic the SPICE transient source functions listed below.

SPICE Advanced Design System
EXP() exp_pulse(time, low, high, tdelay1, tau1, tdelay2, tau2)
PULSE() pulse(time, low, high, delay, rise, fall, width, period)
PWL() pwl(time, t1, x1,..., tn, xn)
SFFM() sffm(time, offset, amplitude, carrier_freq, mod_index, signal_freq)
SIN() damped_sin(time, offset, amplitude, freq, delay, damping)

HSpice
PU() pulse(time, low, high, delay, rise, fall, width, period)
AM() Not translated.
PL() Not translated.

Comments:

HSpice:
HSpice multiplier on Current sources - This is implemented by making an expression out of the given current value. Example:

HSpice: i1 n1 n2 500ua m=10
ADS: eqn0=(500ua)*(10)
I_Source: i1 n1 n2 Idc=500ua*10

Unsupported HSpice transient functions - AM, PL

Unsupported HSpice syntax extensions -

Data driven PWL source

Repeat and Time Delay specifications in PWL transient function (R=repeat, TD=delay)

PSpice:
Unsupported PSpice syntax extensions

STIMULUS
corner points, TIME_SCALE_FACTOR, VALUE_SCALE_FACTOR