Diode

DXXXXXXX N+ N- MNAME <AREA> <OFF> <IC=VD>

Examples:

DBRIDGE 2 10 DIODE1
DCLMP 3 7 DMOD 3.0 IC=0.2

N+ and N- are the positive and negative nodes, respectively. MNAME is the model name, AREA is the area factor, and OFF indicates an (optional) starting condition on the device for DC analysis. If the area factor is omitted, a value of 1.0 is assumed. The (optional) initial condition specification using IC=VD is intended for use with the UIC option on the .TRAN statement, when a transient analysis is desired starting from other than the quiescent operating point.

Diode Model

The diode model is general enough to work for both junction diodes and Schottky barrier diodes. The DC characteristics of the diode are determined by the parameters IS and N. An ohmic resistance, RS, is included. Charge storage effects are modeled by a transit time, TT, and a non-linear depletion layer capacitance which is determined by the parameters CJO, VJ, and M. The temperature dependence of the saturation current is defined by the parameters EG, the energy and XTI, the saturation current temperature exponent. Reverse breakdown is modeled by an exponential increase in the reverse diode current and is determined by the parameters BV and IBV (both of which are positive numbers).

Diode Model Parameters -

Name MeaningUnitsDefaultArea
ISsaturation current A 1.0E-14 *
RS ohmic resistance W 0*
N emission coefficient 1
ISR recombination currentA 0
NR emission coefficient for ISR 2
IKF high-injection knee currentA infinite
TTtransit-time s0
CJO zero-bias junction capacitance°F0 *
VJ junction potential V 1
M grading coefficient 0.5
EG activation energy eV 1.11
0.69 Sbd
0.67 Ge
XTI saturation-current temp. exp 3.0
2.0 Sbd
NBVreverse breakdown ideality factor 1
IBVL low-level reverse breakdown knee current A 0
NBVL low-level reverse breakdown ideality factor 1
KF flicker noise coefficient 0
AF flicker noise exponent 1
FCcoeff for forward-bias depletion capacitance 0.5
BVreverse breakdown voltage Vinfinite
IBV current at breakdown voltageA1.0E-3
TIKF IKF temperature coefficient (linear) °C-1 0
TBV1 BV temperature coefficient (linear) °C-1 0
TBV2 BV temperature coefficient (quadratic) °C-2 0
TRS1 RS temperature coefficient (linear) °C-1 0
TRS2 RS temperature coefficient (quadratic) °C-2 0

* The parameter scales with area.

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