Download Spice Lecture

INTRODUCTION
Spice
Excel
SPICE
Simulation Program with Integrated Circuit Emphasis
SPICE is a program which can be used to
simulate analog electronic circuits
Analog filter circuits have a parameter
called a ‘Transfer Function’ which maps
input to output with relation to frequency
v_in
circuit
v_out
Analog filter circuits have a parameter
called a ‘Transfer Function’ which maps
input to output with relation to frequency
Analog filter circuits have a parameter
called a ‘Transfer Function’ which maps
input to output with relation to frequency
Analog filter circuits have a parameter
called a ‘Transfer Function’ which maps
input to output with relation to frequency
Analog filter circuits have a parameter
called a ‘Transfer Function’ which maps
input to output with relation to frequency
Analog filter circuits have a parameter
called a ‘Transfer Function’ which maps
input to output with relation to frequency
A netlist is a text version of the circuit
which describes the components and
values for the computer to interpret and
solve
A netlist is a text version of the circuit
which describes the components and
values for the computer to interpret and
solve
A netlist is a text version of the circuit
which describes the components and
values for the computer to interpret and
solve
A netlist is a text version of the circuit
which describes the components and
values for the computer to interpret and
solve
A netlist is a text version of the circuit
which describes the components and
values for the computer to interpret and
solve
A netlist is a text version of the circuit
which describes the components and
values for the computer to interpret and
solve
A netlist is a text version of the circuit
which describes the components and
values for the computer to interpret and
solve
* Basic DC circuit
V1 1 0 20
R1 3 1 4k
R2 3 2 10k
V2 2 0 -10
R3 3 0 8k
.OP
.END
A netlist is a text version of the circuit
which describes the components and
values for the computer to interpret and
solve
* Series_RLC Circuit
V1 1 0 SIN(0 5 1k) AC 1
R1 2 1 50
L1 2 3 100mH
C1 3 0 1uF
.AC DEC 100 1 10k
.END
WHAT IS SPICE?
Spice is a software program that simulates electronic circuits and outputs the
circuits’ basic characteristics such as:
–Voltage
–Current
–Resistance
at any location in the circuit
HSpice is a version used in Unix
PSpice is a version used in Windows
T-Spice simpler tool meant for smaller circuits – this is what you will use in the lab
LT spice is free http://www.linear.com/designtools/software/
OptiSPICE is the best because it was written by your professor.
WORKFLOW
• Create an Spice input file that describes the
circuit
• Run Spice
• Inspect the output
THE NETLIST
- A netlist describes the circuit to the program
- Node 0 is always GROUND
name
node
value
R_R1 1 0 100
C_C1 1 2 0.01592u
V_V1 2 0 dc 0.0 ac 1.0 sin(0.0 1.0 1.0 0 0)
THE INPUT FILE
Title “my filter circuit”
.options ingold=2
R_R1 1 0 100
C_C1 1 2 0.01592u IC=0
V_V1 2 0 dc 0.0 ac 1.0 sin(0.0 1.0 1.0 0 0)
.print ac V(1)
.ac LIN 100 0.001 1e+06
.op
-The title must be the first line in the netlist
.END
(in order to recognize the options command)
- R1 = 100Ω (Ohms)
- C1 = 0.01592uF (micro Farads) with initial condition of 0
- V1 = sine wave with 1Hz frequency, 0 to 1V magnitude
- Print ac voltage at node 1
- Want 100 frequency points from 0.001 to 1e+06
LTSpice – demo later
Others might be available
• Hspice (not likely and difficult to use)
• Instructions likely obsolete
• PSpice
• Not sure we have full licence
• Tspice
• Might be ok – netlist based I think.
• OptiSpice – the best (it’s mine).
RUN T-SPICE
•
All Programs ->Tanner EDA -> T-Spice...
VIEWING OUTPUT
Using PSpice
Using HSPICE
TRANSFER FUNCTION
•
Magnitude Plot - DB vs Hz (log
scale)
•
Phase Plot - Degrees vs Hz
Together these plots show the transfer function of
the circuit at different frequencies
For HSPICE and PSPICE use Excel to generate
the plots
BIPOLAR JUNCTION
TRANSISTOR
Input Voltage
Output Voltage
•
3-terminals: Collector, Base, and Emitter
• Common Emitter Amplifier
• input = base with respect to the emitter
• output = collector with respect to the emitter
•
Most commonly used configuration for transistor-based
amplifiers as it produces the highest voltage, current, and
power gain.
BJT
OUTPUT FROM HSPICE
SOME USEFUL NETLIST STATEMENTS
•
•
Analysis Types:
•
Operating Point (.OC) - Voltage at
each node and current from voltage
sources
•
AC Analysis (.AC) - Small signal
model output at different frequencies
•
Transient (.TRAN) - Circuit output as
time passes
Scale factors:
T : E+12
G : E+9
MEG : E+6
K : E+3
M : E-3
U: E-3
N: E-9
P: E-12
F: E-15
SOME USEFUL NETLIST STATEMENTS
•
Components:
Netlist Name
Component Type
Rname
Resistor
Cname
Capacitor
Lname
Inductor
Vname
Voltage Source
Voltage source: Vname N+ N- <DC=> DCValue
Iname
Current Source
Current source: Iname N+ N- <DC=> DCValue
Qname
Bipolar Transistor
Mname
MOSFET
Example
Rname N+ N- Value
Cname N+ N- Value <IC=Initial Condition>
Lname N+ N- Value <IC=Initial Condition>
Qname C B E BJT_modelName
Mname ND NG NS <NB> ModName <L=VAL>
<W=VAL>
Sweep Distributions:
- DEC : Log distributions of points
- LIN: Linear distribution of points
LTSpice - demo
TIPS IN EXCEL
FORMAT CELLS
• In the menu, choose Format Cells
Scientific Notation:
0 decimals
Time [s]
Vout [V]
0.E+00
0.000
1.E-10
-0.008
2.E-10
-0.007
3.E-10
0.034
4.E-10
0.140
5.E-10
0.322
6.E-10
0.588
7.E-10
0.934
8.E-10
1.355
9.E-10
1.839
1.E-09
2.373
Number: 3 decimals
Excel can split text from one column into
multiple columns using the command “Text to
Columns”
$
• $ is used with cell coordinates, signifies
leaving that coordinate constant
• Example: rearrange v=d/t to give d=v*t
The
code
PASTE SPECIAL
• Example: Make a row of data negative
• Copy cell with -1 value, highlight cells that
you want to become negative of the current
values, Edit Paste Special Multiply
Positive
“not yet
Negative”
0.400
0.400
-0.008
-0.008
-0.007
-0.007
-1
Positive
Negative
0.400
-0.400
-0.008
0.008
-0.007
0.007
• Other: transpose, add…
BEST FIT LINE
• Right-click on a data point, choose Add
Trendline using type: Linear, options: display
equation on chart and R squared value.
STATISTICS
• must have the Analysis Toolpak (go to Tools
Add-ins, and install).
• tools - data analysis - regression - x and y
ranges - click residuals SUMMARY
OUTPUT
Regression Statistics
Multiple R
0.999997109
R Square
0.999994218
Adjusted R Square
0.999991328
Standard Error
1182.326494
Observations
4
End
NOW TO APPLY YOUR
KNOWLEDGE!