Zener Diode

Overview

This component provides a Zener diode. The behaviour is identical to an ideal diode except when the reverse bias voltage ($-V_D$) is greater than the breakdown voltage ($V_b$).

Ideal Case

When $V_D ≥ -V_b$ the diode obeys the Shockley Diode Equation:

$$I_D = I_S (e^{V_D/nV_T} - 1)$$

where $I_D$ is the diode current, $I_S$ is the reverse-bias saturation current and $V_D$ is the voltage across the diode.

Thermal voltage $V_T$ is defined by $KT/q$ where $K$ is the Boltzmann constant, $T$ is the temperature at the junction and $q$ is the electron charge.

The idealty factor $n$ is 1 for an ideal diode. Higher values account for imperfect junctions.

Breakdown Case

When $V_D < -V_b$ current is given by:

$$I_D = I_S (e^{V_D/nV_T} - 1) + (V_D+V_b)/R$$

where $R$ is the breakdown resistance.

Parameters

Name	Description	Unit
Name	A unique identifier for the component.	-
Saturation Current	($I_S$) Reverse-bias saturation current	Amperes
Idealty Factor	($n$)	-
Breakdown Voltage	(V_b) Reverse bias where the diode	Volts
Breakdown Resistance	(R) Fixed resistance in reverse bias beyond the breakdown voltage	Ohms
Forward Bias Resistance	The fixed resistance value in forward bias	Ohms

Usage Instructions

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