Transcript Diode Modelling

EC538 Selected Topics in Electronics
Lab 1
LTspice Intro
Eng. Nihal Tawfik
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Lab Objective
Proper understanding Devices Basics
Semiconductors Devices Models
PN Junction
MOSFETS
(Diode)
VLSI Fabrication and Layout
Digital/Analog Course Project
Tools :
 LT Spice IV
 Electrical
http://ltspice.linear.com/software/LTspiceIV.exe
ftp://ftp.gnu.org/pub/gnu/electric/electric-9.03.jar
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Spice
› SPICE: Simulation Program with Integrated
Circuit Emphasis
› Developed at UC Berkeley in the early
70’s.
› Commercial versions:
– Hspice: Hailey-Spice owned by Synopsis run
under Unix
– Spectre: Cadence Unix Tool
– Eldo: Mentor Tool
– Pspice: Personal Spice owned by Cadence
– LTSpice (FreeWare), Mica Spice, …
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Spice Netlist
› Circuit are described in a text file called
“Netlist”.
› Netlists are difficult to create for large
circuits.
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Spice GUI
› Therefore, Graphical Circuit Interface has
been developed.
› Netlists are then automatically generated.
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Analysis Types
1- Operating Point
› Using LTSpice:
Find the corresponding voltages and current
in the below circuit :
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Analysis Types (ctd.)
2- DC Sweep
› Using LTSpice:
Find the IV characteristics of the MUR460
diode.
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Analysis Types (ctd.)
3- AC Sweep
› Using LTSpice:
Find the operating bandwidth for the below
circuit:
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Analysis Types (ctd.)
4- DC Sweep
› Using LTSpice:
Plot the output and input voltage for the
below circuit:
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Quick Hints on LTspice
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To start a new schematic:
To add a component:
To rotate an element : CTRL+R
To place ground:
To specify the simulation type: Edit ->Spice Analysis
To display the cursors, right click on the expression
name at the top of the plot pane.
› In AC sweep Analysis, the Bandwidth is displayed by right
clicking while holding down the CTRL key.
› To edit a model:
Go to :…\Program Files\LTC\LTSpiceIV\lib\cmp
Choose : standard.mos : for MOSFET models
standard.dio
standard.bjt
: for diode models
: for BJT models
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