ADS Tutorial # 6 Customize MOSFET Model and Simulation ppt

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ADS Tutorial # 6
Customize MOSFET Model and Simulation


1. Circuit Construction
a. From Component Pallet
In component pallet, find “Device-MOS” and choose “Bsim3”, as shown in
Figure 1. According to the application, different MOSFET model may be taken.


Figure 1

b. Detailed parameters in “Bsim3” model are shown in Figure 2. If there is no value of
any parameter, it means the default value is taken. The default value for each parameter
can be found in website.

2

Figure 2


c. Above Bsim3 model, there is a MOSFET model, “NMOS”. Place it on schematic.
Make sure the model name use in NMOS symbol is matched that in Bsim 1 model,
as shown in Figure 3.


Figure 3

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2. Do DC simulation on a single MOSFET transistor (Figure 4)

a. Sweep Vds and measure Id, I-Probe 1.
b. Parameter sweep Vgs.



Figure 4


c. Id-Vds with parameter sweeping Vgs (Figure 5).

m1
Vds=
I_Probe1.i=0.002
Vgs=3.000000
3.500
m2
Vds=
I_Probe1.i=0.001
Vgs=2.500000
4.100
123405
0.5
1.0
1.5
2.0

2.5
0.0
3.0
Vds
I_Probe1.i, mA
m1
m2

Figure 5









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3. Simulate common-source amplifier with drain resistance load

a. Use DC simulation to find out the bias point, as shown in Figure 6.


(a)

123405
1
2
3

4
0
5
Vgs
Vo, V

(b)

Figure 6

b. From Figure 6 (b), we could tell Vgs=2.2 V giving better bias point.
c. AC simulation is used to find out the voltage gain, 13.7 dB, as shown in
Figure 7.


5


(a)


m1
freq=
dB(Vo/Vi)=10.778
14.14GHz
1E4 1E5 1E6 1E7 1E8 1E9 1E101E3 1E11
5
6
7
8

9
10
11
12
13
4
14
freq, Hz
dB(Vo/Vi)
m1

(b)

Figure 7