mosfet,mosfet amplifier configuration,mosfet amplifier inputoutput

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Page 1 of 33 University of North Carolina at Charlotte Department of Electrical and Computer Engineering Laboratory Experimentation Report Name: Ethan Miller Date: July 31, 2014 Course Number: ECGR 3155 Section: L01 Experiment Titles: [8] MOSFET, [9] MOSFET Amplifier Configuration, [10] MOSFET Amplifier Input/output Lab Partner: None Experiment Numbers: 8, 9, 10 Objectives: Experiment 8: The intention of this experiment was to examine the basic regions of operation of a single stage MOSFET transistor. Experiment 9: The purpose of this experiment was to examine the three different configurations of a single stage MOSFET amplifier: common source, common gate and common drain often called source follower to determine the midband voltage gain. Experiment 10: The purpose of this experiment was to examine the input, output impedances and the midband voltage gain of a single stage MOSFET amplifier. Equipment List: Items Asset # MB-106 Breadboard 00000001 CD4007UBE 00000002 Decade Resister Box 00000003 Agilent 33509B Function Generator 00000004 Agilent Infinii Vision 2000-X Oscilloscope 00000005 E3612A Power Supply 00000006 Agilent 34461A 6 ½ Digital Multimeter 00000007 Cadence Design System (P-Spice) 00000008 15KΩ, 22KΩ, 10KΩ, 16KΩ 00000009 1uF 00000010

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Page 1: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 1 of 33

University of North Carolina at Charlotte

Department of Electrical and Computer Engineering

Laboratory Experimentation Report

Name: Ethan Miller Date: July 31, 2014

Course Number: ECGR 3155 Section: L01

Experiment Titles: [8] MOSFET, [9] MOSFET Amplifier Configuration, [10] MOSFET

Amplifier Input/output

Lab Partner: None Experiment Numbers: 8, 9, 10

Objectives:

Experiment 8:

The intention of this experiment was to examine the basic regions of operation of

a single stage MOSFET transistor.

Experiment 9:

The purpose of this experiment was to examine the three different configurations

of a single stage MOSFET amplifier: common source, common gate and common drain

often called source follower to determine the midband voltage gain.

Experiment 10:

The purpose of this experiment was to examine the input, output impedances and

the midband voltage gain of a single stage MOSFET amplifier.

Equipment List:

Items Asset #

MB-106 Breadboard 00000001

CD4007UBE 00000002

Decade Resister Box 00000003

Agilent 33509B Function Generator 00000004

Agilent Infinii Vision 2000-X Oscilloscope 00000005

E3612A Power Supply 00000006

Agilent 34461A 6 ½ Digital Multimeter 00000007

Cadence Design System (P-Spice) 00000008

15KΩ, 22KΩ, 10KΩ, 16KΩ 00000009

1uF 00000010

Page 2: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 2 of 33

Relevant Theory/Background Information:

Experiment 8:

The MOSFET device is a four terminal device with connections called the drain,

gate, and the body, a symbol of a MOSFET is shown in Figure 1. The MOSFET body has

to be connected to ground in most situations to ensure the region of operation. Most

MOSFET chips have the body internally connected to ground but for diagrams in P-Spice

the body is always connected to ground or to the source terminal.

To understand how a MOSFET operates, two external DC power supplies are

connected and are called gate to source voltage and drain to source voltage, shown in

Figure 2. The drain to source voltage or known as VDS can cause a drain to source current

known as IDS. This path of the IDS current can be controlled by VGS. For example a high

VGS can cause effortless flow of IDS. This current of IDS acts like a channel, or like a

capacitor. The capacitor is form between the gate voltage and the channel region of the

MOSFET and the oxide layer acting as the dielectric. A positive gate voltage causes a

positive charge to collect on the topmost plate of the capacitor. The negative charge on

the lowermost of the capacitor is formed by electrons induced into the channel. Thus an

electric field develops in an upright direction. This field controls the amount of charge in

the channel, determines the channel conductivity and the current will flow through the

channel when a VDS is applied. Hence MOSFET means metal-oxide-semiconductor field-

effect transistor.

Figure 1: MOSFET Diagrams

To ensure that parallel plate capacitor is operating in the saturation region the

voltage across the oxide must exceed the threshold voltage. The threshold voltage is the

value of VGS at which the number of electrons accrues in the channel region to form a

conducting channel. The additional amount of VGS over the threshold voltage is called the

over drive voltage. This voltage is magnitude that determines the charge in the channel.

Figure 2: MOSFET Operation Circuit

A MOSFET has three different regions of operation called ohmic/triode,

saturation and pinched off point. For a MOSFET to operate as an amplifier the MOSFET

has to be in the saturation region. Saturation of MOSFET occurs when VDS is greater than

or equal to the overdrive voltage.

NMOSFET PMOSFET

000

VDS

VGS

Page 3: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 3 of 33

In this region VDS has no effect on the channel shape and charge of the drain

MOSFET. As soon as the VDS saturation was equal to the overdrive voltage, the current

through the drain is constant. Thus the constant current must saturate the MOSFET. The

saturation region only exists where the MOSFET operation curve when VDS increases

and the curve begins to flatten. The current flowing through the device in the saturation

region of operation is given in Equation 1. In the saturation region the MOSFET can be

connected to act similar to a diode shown in Figure 3.

(Eqn.1)

Triode region or known as the ohmic region occurs when VDS is less than or equal

to the overdrive voltage. In this region VDS has an effect on the channel of the drain

current at which the electrons flow through. In the creation of the MOSFET operation

curve the slope is proportional to the overdrive voltage, but as the curve starts to bend the

channel resistance was increasing proportional to VDS. The ohmic region only exists

where VDS is very small and the curve is linear. The current flowing through this device

in the triode/ohmic region is given by Equation 2. The two physical parameters of W/L

and are known as the transconductance. Also note that the ohmic region can be

used for a voltage controlled resister, where the drain to source resistance can be found

by Equation 3.

(Eqn.2)

(Eqn.3)

At the point when VDS saturation was equal to the overdrive voltage the channel

at the drain ends gives to a rise called pinch-off point. Here in this region of the MOSFET

found the value of the threshold voltage.

Figure 3: Diode Connected MOSFET

00

VDS=VGS

Page 4: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 4 of 33

Experiment 9:

There are three basic configurations and are generally defined as common source,

common gate, and common drain. Each one of this configurations exhibit different

characteristics for a more desirable design. Shown in Table 1 is the comparison between

the different MOSFET amplifiers. Normally, the common gate and the common source

have a lower frequency bandwidth than the common drain. This was found by the effects

caused by the internal capacitance and how the external capacitance is configured in the

amplifier. Another caused for the loss of bandwidth is the Miller Effect. The Miller effect

is a technique for replacing the bridge capacitance of the transistor by an input equivalent

capacitance.

Common-Source Common-Gate Common-Drain

Input Impedance High ( ) Low High

Output Impedance High Very High Low

Current Gain High ( ) Low ( ) High

Voltage Gain Medium High Low

Power Gain Very High Low Medium

Phase Gain 180 0 0

Table 1: MOSFET Comparison

Experiment 10:

In the prior experiments the DC biasing and AC amplification of a MOSFET have

been examine. This MOSFET experiment trial will build upon the previous experiments

as well be introduced to input and output impedances of a MOSFET amplifier. The

amplifier selected for this experiment is the common source shown in Figure 9.

Procedure for suitably biasing the MOSFET amplifier and setting up AC amplification

will be investigated as well as, techniques for measuring the input and output

impedances.

The input impedance of an amplifier is difficult measure, in the midband gain the

impedances is predominantly resistive. The input resistance/impedance is defined as the

ratio of input voltage divided by the input current. Input impedances are calculated from

the small signal circuit/AC Equivalent circuit by looking into the input with all current

source replaced as open circuit and voltages source as short circuits.

The importance of input impedances shows how low input impedances reflect on

the overall circuit as well as high input impedances. Low input impedances generally

have a poor low-frequency response and large power requirement. For example the

LM741 op-amp has high input impedance which results in a good low-frequency

response and low input power consumption. As well as output impedance play a role in

the circuit. Output impedance is restive in the midband gain and generally a complex

measure. To calculate the output impedance the load is removed and the impedance is

found by looking back into the small signal circuit/AC Equivalent circuit. Once again it is

essential all current sources with an open circuit and voltage sources with a short circuit.

The importance of the output impedance is the offer of power to an amplifier. The

idyllic output impedance is zero; an amplifier with low output impedance preserve a

larger output current without a major reduction of the output voltage.

Page 5: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 5 of 33

Experimental Data/Analysis:

Experiment 8:

Shown in Figure 4 was constructed to have a VGS at 2V, 1.9V and 2.4V. By

changing the VDS voltage the current IDS was changed. With VDS held at 5V the value of

the threshold voltage was found to be 1V, .81V and .71V when VDS saturation was

equaled to the overdrive voltage. Shown in Table 2 and Figure 7 shows the MOSFET

operation curve when VGS was held at a certain voltage and VDS was changing in

increments of .25V.

Saturation of MOSFET occurred when VDS was greater than or equal to the

overdrive voltage. In this region VDS had no effect on the channel shape and charge of the

drain current. As soon as the VDS saturation was equal to the overdrive voltage the

current through the drain was constant. Thus the constant current must saturate the

MOSFET.

Triode region or known as the ohmic region occurred when VDS was less than or

equal to the overdrive voltage. In this region VDS has an effect on the channel of the drain

at which the electrons flow through. In the creation of the MOSFET operation curve the

slope was proportional to the overdrive voltage, but as the curve started to bend the

channel resistance was increasingly proportional to VDS.

At the point when VDS saturation was equal to the overdrive voltage the channel

at the drain ends and gave a rise to a term called channel pinch-off. Here in this region of

the MOSFET the threshold voltage was found and was estimated to about 1V, .81V and

.71V. In this region current maintained to flow through the pinch off point in the channel

and the electrons that reached the drain ended up in the drain terminal which were

accelerated through the depletion region Also note that any increase in VDS that was

above VDS saturation, appeared as a voltage drop across the depletion region.

Figure 4: MOSFET Operation Circuit

Figure 5: MOSFET Resistance Circuit

nnMOS

0

00

VDS

VGS

Amps

nnMOS

00

VGS

Resistance

Page 6: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 6 of 33

Figure 6: MOSFET Diode Circuit

VGS

(V)

VDS

(V)

IDS

(µA)

VGS

(V)

VDS

(V)

IDS

(µA)

VGS

(V)

VDS

(V)

IDS

(µA)

2 0 0.0804 1.9 0 0.079 2.4 0 0.107

2 0.25 249.7 1.9 0.25 216.7 2.4 0.25 366.7

2 0.5 356.3 1.9 0.5 290.05 2.4 0.5 613.8

2 0.75 378.23 1.9 0.75 302.3 2.4 0.75 735.5

2 1 383.2 1.9 1 305.8 2.4 1 773.4

2 1.25 386.9 1.9 1.25 308.9 2.4 1.25 786.1

2 1.5 389.1 1.9 1.5 309.6 2.4 1.5 792.6

2 1.75 390.5 1.9 1.75 310.8 2.4 1.75 797.2

2 2 392.1 1.9 2 311.8 2.4 2 800.9

2 2.25 393.4 1.9 2.25 312.9 2.4 2.25 803.8

2 2.5 394.5 1.9 2.5 313.7 2.4 2.5 806.5

2 2.75 395.5 1.9 2.75 314.9 2.4 2.75 808.6

2 3 396.4 1.9 3 315.3 2.4 3 810.7

2 3.25 397.4 1.9 3.25 315.9 2.4 3.25 812.8

2 3.5 398.1 1.9 3.5 316.4 2.4 3.5 814.6

2 3.75 399 1.9 3.75 317.2 2.4 3.75 816.3

2 4 399.8 1.9 4 317.8 2.4 4 817.9

2 4.25 400.6 1.9 4.25 318.4 2.4 4.25 819.3

2 4.5 401.2 1.9 4.5 319.1 2.4 4.5 820.6

2 4.75 401.9 1.9 4.75 319.5 2.4 4.75 822.4

2 5 402.5 1.9 5 320.1 2.4 5 823.8

Table 2: MOSFET Operation

nnMOS

0

R

VDD

5Vdc

0

Volts

Page 7: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 7 of 33

Figure 7: CD4007UBE MOSFET Operation

VGS (V) Resistance (Ω) Calculated Resistance (Ω) Percent Error (%)

0 infinite infinite 0

1.5 1518.5 4962.77 69.40216855

1.9 839.52 2166.84 61.2560226

2 731.58 1899.33 61.48220688

2.4 506.701 1271.45 60.14778403

2.5 473.34 1174.39 59.69482029

3 455.887 849.97 46.36434227

4 286.379 547.49 47.69237794

5 225.791 403.79 44.08207236

Table 3: Ohmic Resistance of MOSFET

0

100

200

300

400

500

600

700

800

900

0 0.25 0.5 0.75 1 1.25 1.5 1.75 2 2.25 2.5 2.75 3 3.25 3.5 3.75 4 4.25 4.5 4.75 5

Dra

in S

orc

e C

urre

nt

(µA

)

Drain Source Voltage (V)

CD4007UBE MOSFET Operation

VGS=2V

VGS=1.9V

VGS=2.4V

Saturation Region Vds > =Vov

Triode/ohmic

region

Vds ≤ Vov

Vds-sat = Vov

CD40007UBE MOSFET Operation

ECGR 3155-Systems and

Electronic Lab

Experiment # 8 MOSFET

Ethan Miller

Page 8: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 8 of 33

VDD

(V)

Resistance

Ω

IDS (A) VDS

(V)

Calculated VDS

(V)

Percent Error

(%)

5 33000 0.00010422

4

1.5606 2.004 22.1257485

5 15130 0.00021373

6

1.76618 2.234 20.94091316

5 11731 0.00026877 1.84706 2.327 20.62483885

5 9500 0.00032402

9

1.92172 2.410 20.26058091

Table 4: MOSFET Diode Voltages of Drain to Source

Shown in Figure 5 was constructed for the demonstration for the ohmic resistance as the

MOSFET operation curve was form. Table 3 showed these different resistances in the ohmic

region. When VDS was less than or equal to the threshold voltage the ohimc resistance was found

to be infinite or rather large. As the VDS was greater than or equal to the threshold voltage the

ohimc resistance decreased proportional to the increase in VDS. When VDS was kept small or

relatively close to 0V, the MOSFET behaved as a linear resistance, thus the value of gate voltage

was controlled. The MOSFET could be used for a voltage controlled resistance, and some

examples are audio and video frequency. It is necessary to create a voltage controlled resister

from MOSFET because a requirement of current for an input resistance of an electronic device.

Percentage Errors were calculated and were found to be around 40 to 60 percent error

between the measured and calculated values. This high percent error could have been caused by

the fact of the MOSFET had a different threshold voltage and transconductance parameter than

what was calculated by.

Shown in Figure 6 was constructed for the demonstration of a diode connection

MOSFET. Table 4 shows these different values of VDS, as the drain voltage was kept constant at

a nominal value of 5V. When there was a higher current flowing from drain to source, a higher

resistance was needed. The output voltage of VDS was increasingly proportional to the current

and resistance. Since the gate voltage was connected to the drain terminal the MOSFET was

always in the saturation region because VDS was greater than the threshold voltage. As VDS was

less than or equal to the overdrive voltage the MOSFET entered the triode region. This only

happened when VGS was less than the threshold voltage. As a result when the gate terminal was

connected to the drain terminal the MOSFET acted like a switch, hence a diode connected

MOSFET. A MOSFET would be connected like a diode to ensure a level of protection for a

standard diode in a circuit. The drain to source terminal of the MOSFET protected the output

from damage when the MOSFET is used as a switch in relays, switch motors and any inductive

circuits. VDD would be important voltage to set for a design to ensure the voltage at VDS is at

certain level to drive the proceeding circuit.

Page 9: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 9 of 33

Laboratory Computation

Percent Error

MOSFET in Triode/Ohmic Region

For

MOSFET in Saturation Region

Page 10: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 10 of 33

For

Pre-Lab

Page 11: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 11 of 33

Experiment 9:

A MOSFET amplifier was constructed and biased to ensure the amplifier was in

the saturation region for a specification of IDS = 400µA, VS = 4V, VD = 9V, VGS = 2.3V,

VT = 1.19V, and the transconductance (KN) value was 650 µA/V2. The resister values

were calculated and are shown in Equations 4, 5 and 6. Also shown under the laboratory

computation section are the calculated DC voltages for the MOSFET amplifier circuit.

The MOSFET had a saturation region requirement which was found to have a VDS

saturation greater than or equal to the overdrive voltage. The calculated VDS saturation

was found to be 1.11V which was much less than VDS. Shown in Figure 8 was the P-

Spice DC biasing for the MOSFET amplifier circuit. From the P-Spice simulation the DC

voltages and IDS current was found to be relatively close to the calculated values. Also

note the capacitors were open during the DC calculation analysis to ensure the AC

analysis was not affected by the DC analysis. During the simulation the AC signal went

through the capacitors and a DC signal was blocked. Capacitors were blocked because of

the complex quantity a capacitor had. The resistance of a capacitor equation was

and

when a DC signal was sent though the capacitor no frequency was measured. Hence

capacitors block DC signals and the resistance was infinite.

Figure 8: P-Spice DC Biasing Amplifier Circuit

Three different MOSFET amplifier configurations were constructed during the lab. The

following were the configurations common source, common gate and common drain. Show in

Table 5 was the measured DC voltages for each configuration. Also note that the phase angle

was measured and the observed value was found to be 90 degrees from the output AC signal to

the input AC signal. The DC voltages measured in the lab had the same value between the

different configurations.

Page 12: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 12 of 33

This was expected because each configuration needed to be biased in the same way to

ensure a comparison between the midband voltage gains and the MOSFET needed to be in the

saturation region. Each of these configurations was calculated to find the overall midband

voltage gain. This midband voltage gain was calculated from the small signal/AC equivalent

circuit. Gains for each of the configurations are shown in Equations 8, 9 and 10. In order to

calculate the midband voltage gain, gm (parameter which relates ids (AC current) and vgs (gate to

source AC voltage) in the MOSFET) was first calculated. Gm was found by calculating the

partial derivative of the total current through the MOSFET shown in Equation 7. The first term

in the equation was distinguished as the DC current of the MOSFET. The second term in the

equation was signified as the current which was directly proportional to the input signal vgs. The

third term in the equation was a current element which was proportional to the square of the

input signal vgs. This term was unwanted because it symbolized a nonlinear distortion. In order to

decrease this distortion, the input signal needed to be kept small so that vgs was much less than

the 2 times the overdrive voltage. When this was satisfied, the equation neglected the last term.

Thus resulting in the partial derivative of gm was KN (transconductance parameter) times the

overdrive voltage.

Configuration VD VG VS Phase (degrees)

Common Source 8.374 6.367 4.349 90

Common Gate 8.380 6.367 4.349 90

Common Drain 8.380 6.367 4.349 90

Table 5: Laboratory DC Voltages

Shown in Figures 9 and 10 were the constructed amplifier circuits for common source

and common gate. P-Spice was used to give a theoretical midband voltage gain measurement for

realistic lab values. Shown in Figures 11 and 12 were the P-Spice midband voltage gain and the

low and high cutoff frequencies. P-Spice measured the midband voltage gain at 4.3474 peak to

peak volts for the common source and 4.372 peak to peak volts for the common gate amplifiers.

These two configurations had very similar midband voltage gains as well as low and high cutoff

frequencies from the hand calculations and P-Spice simulations. The common source and

common gate midband voltage gain was measured by dividing the output voltage by the input

voltage. During the midband voltage gain of the P-Spice and laboratory graphs all of the internal

and external capacitors were acting as an open circuit and the dependent source of gm Vbs acted

like short (for current short source a short is an open circuit), shown in Figures 14 and 15 (High

frequency MOSFET amplifier circuit). Theses capacitors acted like a short because of the

amount of frequency at which the voltage gain was at. As descried earlier, the resistance

capacitor equation is

, the higher omega was, the smaller the resistance of the capacitor was.

In this case the resistance value was close to 0 ohms. Laboratory resulted for both the common

source and common gate MOSFET amplifiers were found to be around 5V.

Page 13: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 13 of 33

The common gate was found to be similar to the common source amplifier because of the

configuration the circuit and, since the input voltage was placed at the source terminal the input

voltage was equaled to negative quantity of VGS.

Figure 9: CD4007 MOSFET Common Source Amplifier Circuit

Figure 10: CD4007 MOSFET Common Gate Amplifier Circuit

RD

15K

R1

22K

R2

16KRS

10K

nnMOS

CG

1uF

VIN1Vac

VDD

15Vdc

0

RL

10K

CD

1uF

CS

1uF

RD

15K

R1

22K

R2

16KRS

10K

nnMOS

CG

1uF

VIN1Vac

VDD

15Vdc

0

RL

10K

CD

1uF

CS

1uF

Page 14: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 14 of 33

Figure 11: P-Spice CD4007 MOSFET Common Source Amplifier Voltage Gain

Shown in Figure 17 was the constructed amplifier circuit for common drain. P-Spice was

used to give a theoretical midband voltage gain measurement for realistic lab values. Shown in

Figure 18 was the P-Spice midband voltage gain and the low and high cutoff frequencies. P-

Spice measured the midband voltage gain at 784 millivolts peak to peak. P-Spice only showed

the low cutoff frequency because of the external capacitors, as the frequency got larger there was

no known high cutoff frequency shown. Reasons for this mistake can have caused a different

midband voltage gain, different IDS current through the MOSFET and the model for this

MOSFET could have been changed in the program called cadence design system (P-Spice). This

amplifier configuration was close to the midband voltage gain as well as low cutoff frequency

from the hand calculations and P-Spice simulation. The common drain midband voltage gain was

measured by dividing the output voltage by the input voltage. The laboratory resulted in 820

millivolts peak to peak for the midband voltage gain for this amplifier shown in Figure 19 and

Table 9. [1]

Page 15: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 15 of 33

Figure 12: P-Spice CD4007 MOSFET Common Gate Amplifier Voltage Gain

From all of these different configurations a table was generated to show the main

differences, shown in Table 8. This table shows the bandwidth, midband voltage gain, low and

cutoff frequencies. From observing the resulted values from the table, it seemed that the common

source and common gate can possibly be used for the same purpose in a design. As a result these

two amplifiers had similar resulted values. The only main differences between these two

amplifiers could be found in the input and output impedance, power gain, and the current gain,

which can be a major design specification in order to achieve a certain value at the output to a

preceding circuit. On the other hand the common drain was found to have a very low midband

voltage gain and a high bandwidth (passband). This specific amplifier would most probable be

used for a input stage to a multistage amplifier. In general an amplifier is used in a multistage to

achieve high midband voltage gains and to achieve a certain input and output stage. A common

drain usually has high input impedance and low output impedance. This design is great for a

input and output stage for a multistage amplifier since the current [2]cannot be affected for the

preceding circuit. If the current was to be affected the resulted voltage point in a simple voltage

divider or a power circuit can change. Resulting in changing these values could possible result in

a short in the circuit, the device would not function correctly and in the worst case scenario the

circuit can start to catch on fire due to the movement of electrons inside the wire. [3]

Page 16: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 16 of 33

Figure 13: Laboratory CD4007 MOSFET Amplifier Configuration

Figure 14: Common Source CD4007 MOSFET High Frequency Amplifier Circuit

-0.5

0.5

1.5

2.5

3.5

4.5

5.5

5 50 500 5000 50000 500000 5000000

Gain

Volt

qage

(V/V

)

Frequency (Hz)

CD4007UBE MOSFET Amplifier Configuration

Common Source

Common Gate

CD4007UBE MOSFET Amplifier Configuration

ECGR 3155-System and Electronics Lab

Experiment #9 MOSFET Amplifier Configuration

Ethan Miller

R2

16K

ro

250K

R1

22K

RD

15K

RL

10K

VIN gm VGS

0 0 0

VGS++

GATE

gm Vbs

Csb

CdbCgs

Cgd

BODY

--VOUTVGS--

++VOUT DRAIN

SOUCRE

--Vbs

++Vbs

Page 17: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 17 of 33

Frequency

(Hz)

VIN

(mV)

Vout

(mV)

Gain (pk-

pk)

Frequency

(Hz)

VIN

(mV)

Vout

(mV)

Gain (pk-

pk)

10 101 3.2 0.0316831

7

10000 105 540 5.1428571

43

20 101 5.6 0.0554455

4

20000 105 540 5.1428571

43

40 103 8.7 0.0844660

2

40000 103 530 5.1456310

68

70 105 10.5 0.1 60000 103 520 5.0485436

89

80 105 15.3 0.1457142

9

80000 103 500 4.8543689

32

100 105 19.7 0.1876190

5

100000 103 470 4.5631067

96

200 105 48 0.4571428

6

200000 103 360 3.4951456

31

400 105 111 1.0571428

6

400000 101 221 2.1881188

12

600 105 165 1.5714285

7

600000 101 153 1.5148514

85

800 105 213 2.0285714

3

800000 103 117 1.1359223

3

1000 105 256 2.4380952

4

1000000 101 94 0.9306930

69

2000 105 394 3.7523809

5

1500000 101 64 0.6336633

66

4000 105 490 4.6666666

7

2000000 101 48 0.4752475

25

6000 105 510 4.8571428

6

2500000 103 39 0.3786407

77

8000 105 530 5.0476190

5

3000000 103 32.2 0.3126213

59

Table 6: Laboratory Tabular Results for a MOSFET Common Source Amplifier

Figure 15: Common Gate CD4007 MOSFET High Frequency Amplifier Circuit

ro

250K

RS

10K

RD

15K

RL

10K

VIN

gm VGS

0

VGS++

GATE

gm Vbs

Csb

CdbCgs

Cgd

BODY

--VOUTVGS--

++VOUT DRAIN

--Vbs

++Vbs

00

SOURCE

Page 18: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 18 of 33

Frequency

(Hz)

VIN

(mV)

Vout

(mV)

Gain (pk-

pk)

Frequency

(Hz)

VIN

(mV)

Vout

(mV)

Gain (pk-

pk)

10 106 10.2 0.0962264

15

10000 101 510 5.0495049

5

20 106 13.2 0.1245283

02

20000 101 510 5.0495049

5

40 105 15.3 0.1457142

86

40000 100 510 5.1

70 105 17.5 0.1666666

67

60000 98 490 5

80 105 20.2 0.1923809

52

80000 100 480 4.8

100 105 23.9 0.2276190

48

100000 98 460 4.6938775

51

200 105 54 0.5142857

14

200000 98 342 3.4897959

18

400 105 115 1.0952380

95

400000 96 213 2.21875

600 105 167 1.5904761

9

600000 96 147 1.53125

800 105 217 2.0666666

67

800000 96 113 1.1770833

33

1000 105 253 2.4095238

1

1000000 96 90 0.9375

2000 101 390 3.8613861

39

1500000 96 61 0.6354166

67

4000 101 470 4.6534653

47

2000000 96 47 0.4895833

33

6000 101 500 4.9504950

5

2500000 96 38 0.3958333

33

8000 101 510 5.0495049

5

3000000 98 30.6 0.3122448

98

Table 7: Laboratory Tabular Results for a MOSFET Common Gate Amplifier

Figure 16: Common Drain CD4007 MOSFET High Frequency Amplifier Circuit

ro

250K

R2

16K

RL

10K

gm VGS

VGS++

GATE

gm Vbs

Csb

Cdb

Cgs

Cgd

BODY

--VOUT

VGS--

++VOUT

DRAIN

--Vbs

++Vbs

R1

22K

RS

10K

VIN

0 0 0 0

SOURCE

Page 19: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 19 of 33

Figure 17: CD4007 MOSFET Common Drain Amplifier Circuit

Midband Voltage

Gain (V/V)

Lower Cutoff

Frequency (Hz)

High Cutoff

Frequency (Hz)

Bandwidth

(Hz)

Configura

tion

P-

Spice

Laborator

y

P-Spice Laborator

y

P-Spice Laborato

ry

P-

Spice

Labor

atory

Common

Source

4.3474 5.1428 133.059

7

1500 286947

00

150000 28694

567

14850

0

Common

Gate

4.372 5.0495 132.746

6

1500 271376

60

150000 27137

527

14850

0

Common

Drain

.784 0.8 48.215 300 N/A 1250000 N/A 12497

00

Table 8: Laboratory Tabular Results for MOSFET Configurations

RD

15K

R1

22K

R2

16KRS

10K

nnMOS

CG

1uF

VIN1Vac

VDD

15Vdc

0

RL

10K

CD

1uF

CS

1uF

Page 20: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 20 of 33

Figure 18: P-Spice CD4007 Common Drain MOSFET Amplifier Voltage Gain

Shown in Figures 14, 15 and 16 are the high frequency models for each the following

configurations: common source, common drain and common gate. In any of these amplifiers the

frequency was varied to find the midband voltage gain. As the frequency started to rise, in the

region between the 0 hertz to the low cutoff frequency the voltage increased by 20db.Here the

low cutoff frequency was determined by the external capacitors. Each capacitor played a major

role in the following equation

. [2]The equivalent resistance for each capacitor

was found by seen resistances when the input voltage was set to 0V and the other capacitors

were replaced by a short. Therefore the lowest cutoff frequency was determined by the highest of

the pole frequencies. In most cases the bypass capacitor at the source is this pole. A pole is where

the denominator of a transfer function (voltage gain) at a certain frequency where it equals zero.

Also note that the cutoff frequency can be found at which the output voltage is at 70.7% of the

maximum amplitude or from the equation

. From this result the higher the value of midband

voltage gain the smaller the bandwidth and the lower the midband voltage gain the larger the

bandwidth. [1]

Page 21: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 21 of 33

Figure 19: Laboratory Common Drain CD4007 MOSFET Amplifier Voltage Gain

The internal capacitors of MOSFET affect the physical operation inside the MOSFET

chip. These capacitors come from the depletion area between the diodes. The following are the

variety of capacitors: gate capacitance, source to body and the drain to body depletion

capacitance. The gate capacitance or normally called the gate electrode formed a parallel plate

capacitor with the channel, by having an oxide layer as the dielectric. This is made by a small

value of VDS which caused a current to flow through the channel. This current was transmitted by

the movement of free electrons voyage from source to drain. The movement or electron drift

velocity is defined by the following equation

and the charge per unit channel

length is defined as

. The next two capacitors deal with the

depletion are of the MOSFET. These capacitors are formed by the positive n source region

(source diffusion) in the reverse biased pn junction and the p type by the n positive drain region

(drain diffusion).

In order to find the high cutoff frequency the following equation must be applied

. The equivalent resistance for each capacitor was found by seen resistances when the

input voltage was set to 0V and the other capacitors were replaced by a short. Therefore the

highest cutoff frequency was determined by the lowest of the pole frequencies. [2]

-0.04

0.06

0.16

0.26

0.36

0.46

0.56

0.66

0.76

0.86

5 50 500 5000 50000 500000 5000000

Gain

Volt

age (

V/V

)

Frequency (Hz)

CD4007UBE MOSFETCommon Drain

Amplifier Configuration

CD4007UBE MOSFET Common Drain Amplifier

Configuration

ECGR 3155-Systems and Electronics Lab

Experiment #9 MOSFET Amplifier Configuration

Ethan Miller

Page 22: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 22 of 33

Frequency

(Hz)

VIN

(mV)

Vout

(mV)

Gain (pk-

pk)

Frequency

(Hz)

VIN

(mV)

Vout

(mV)

Gain (pk-

pk)

10 105 5.2 0.0495238

1

10000 105 86 0.8190476

19

20 105 7.6 0.0723809

5

20000 105 84 0.8

40 105 9.5 0.0904761

9

40000 105 84 0.8

70 105 12.4 0.1180952

4

60000 103 84 0.8155339

81

80 105 15.3 0.1457142

9

80000 103 84 0.8155339

81

100 105 18.5 0.1761904

8

100000 105 84 0.8

200 105 43 0.4095238

1

200000 101 82 0.8118811

88

400 105 67 0.6380952

4

400000 103 78 0.7572815

53

600 105 75 0.7142857

1

600000 103 72 0.6990291

26

800 105 80 0.7619047

6

800000 101 67 0.6633663

37

1000 105 82 0.7809523

8

1000000 101 60 0.5940594

06

2000 105 84 0.8 1500000 101 48 0.4752475

25

4000 105 84 0.8 2000000 101 40 0.3960396

04

6000 105 86 0.8190476

2

2500000 101 32.6 0.3227722

77

8000 105 86 0.8190476

2

3000000 103 28.7 0.2786407

77

Table 9: Laboratory Tabular Results for a MOSFET Common Drain Amplifier

Page 23: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 23 of 33

Laboratory Computation

MOSFET Biasing must be in the Saturation Region

(Eqn.4)

(Eqn.5)

Picked R2 16KΩ for voltage divider

(Eqn.6)

Midband Voltage Gain (V/V) with

Common source MOSFET amplifier

(Eqn.7)

(Eqn.8)

Page 24: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 24 of 33

Common Gate MOSFET amplifier

(Eqn.9)

Common Drain MOSFET amplifier

(Eqn.10)

Experiment 10:

In experiment 9 a MOSFET amplifier was constructed and biased to ensure the

amplifier was in the saturation region for a specification of IDS = 400µA, VS = 4V, VD =

9V, VGS = 2.3V, VT = 1.19V, and the transconductance (KN) value was 650 µA/V2. The

resister values were calculated and are shown in Equations 4, 5 and 6. Shown in Figure 8

was the P-Spice DC biasing for the MOSFET amplifier circuit. From the P-Spice

simulation the DC voltages and IDS current were found to be comparatively near to the

calculated values.

P-Spice was used to ensure a theoretical laboratory results to compare the

laboratory computation results. Shown in Figure 11 (experiment 9) was the P-Spice

midband voltage gain for a common source MOSFET amplifier. From experiment 9 the

laboratory computation was in close proximity to the P-Spice result.

Figure 20: P-Spice Input Impedance CD4007 MOSFET Common Source Amplifier

Page 25: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 25 of 33

Figure 21: Input Impedance CD4007 MOSFET Common Source Amplifier Circuit

Figure 22: P-Spice Output Impedance CD4007 MOSFET Common Source Amplifier

nnMOS

RD

15KR1

22K

R2

16K RS

10K

0

CS

1uF

CG

1uF

CD

1uF

RL

10K

VDD

15VdcVTEST1Vac

RTEST

1K

--VIN

++VIN

Page 26: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 26 of 33

Figure 23: Output Impedance CD4007 MOSFET Common Source Amplifier Circuit

Figure 24: Small Signal CD4007 MOSFET Amplifier Circuit

Two more graphs were generated in P-Spice, input and output impedances. These graphs

found the input impedance to be 9.264 kilohms and the output resistance was 15.103 kilohms.

These graphs were used from the input and output impedance circuit shown in Figures 21 and

23. The input impedance was formed by taking the test voltage divided by the test current and

the output impedance was taking in the same matter but the input voltage was shorted ( a voltage

source short was conducted by a line) and the load resister was disconnected.

During the lab a test resister of 1 kilohms was placed in the MOSFET amplifier circuit to

find the input and output impedances as the frequency was varied from10 hertz to 3 megahertz,

shown in Figures 21 and 23. The reason for this design was the need to find the current through

the voltage source. This was done by taking two oscilloscope probes at each end of the test

resister to measure the voltage drop. The current was found by using the equation of

. Therefore the input and output impedance was found by the following

equation

. [3]

nnMOS

R1

22K

R2

16K

RD

15K

RS

10K

RTEST1KCD

1uF

CS

1uF

CG

1uFVTEST

1Vac

VDD15Vdc

0

--VIN

++VIN

VINR2

16K

R1

22K

0 00 0 00

--VGS

DRAIN

++VOUTGATE

Source

++VGS

--VOUT

OUTPUT IMPEDANCEINPUT IMPEDANCE

gm Vgsr0

250K

RL

10K

RD15K

Page 27: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 27 of 33

The MOSFET observes the input and output impedance by the configuration of the

circuit. Since the test voltage was connected to the gate terminal, the only resistance that was

seen was the two bias resistors R1 and R2 in parallel. Given that the connection between the gate

terminal and the source terminal was never connected. Also, since a voltage was applied to the

gate terminal the input voltage was found at VGS, which turned on the MOSFET. On the other

hand the output impedance was found in the same manner but by applying a voltage at the output

does not turn on the MOSFET because the dependent current source was in dependence of VGS.

[4]

Figure 25: CD4007 MOSFET Input Resistance

From the tabular results of input impedance, shown in Table 10, a graph of the input

impedance was created and shown in Figure 25. The lab resulted in 9537.6 ohms; this was

exceptionally close to P-Spice and hand calculations. The lab resulted in a slight higher value

than P-Spice and hand calculation, this could have been diverted from the actual value by the

tolerances of the resisters.

0

2000

4000

6000

8000

10000

12000

1 10 100 1000 10000 100000 1000000 10000000

INP

UT

RE

SIS

TA

NC

E (Ω

)

FREQUENCY (Hz)

CD4007 MOSFET INPUT RESISTANCE

CD4007 MOSFET INPUT RESISTANCE

ECGR 3155-Systems and Electronics Lab

Experiment #10 MOSFET Amplifier Input/Output

Impedances

Ethan Miller

Page 28: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 28 of 33

Figure 26: CD4007 MOSFET Output Resistance

From the tabular results of the output impedance are shown in Table 11, a graph of the

output impedance was created and shown in Figure 26. The lab resulted in 16430 ohms; this was

similarly to what P-Spice and hand calculations. The lab resulted in a higher value than P-Spice

and hand calculation, this could have been diverted from the actual value by the tolerances of the

resisters and since the resisters had tolerances the current of drain to source could have changed

which may have changed the output resistance (r0).

Since the common source configuration had the same resister values as the common

source amplifier in experiment 9, the midband voltage gain and the DC voltages were found to

be similar. Shown in Figure 27 was a better diagram at the midband voltage gain MOSFET

common source amplifier. This voltage gain resulted in approximately 5 voltage peak to peak,

this was much higher than the P-Spice and hand calculation. The chip that was used was

CD4007UBE (1CCX6ZK E4) this chip may have had different characteristics of current flow

through the MOSFET.

0

5000

10000

15000

20000

25000

1 10 100 1000 10000 100000 1000000 10000000

INP

UT

RE

ISIS

TA

NC

E (Ω

)

FREQUENCY (Hz)

CD4007 MOSFET OUTPUT

RESISTANCE

CD4007 MOSFET OUTPUT RESISTANCE

ECGR 3155-Systmes and Electronics Lab

Experiment #10 MOSFET Amplifier Input/Output

Impedance

Ethan Miller

Page 29: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 29 of 33

Frequency

(Hz)

Vtest

(mV)

Vin

(mV)

Resistance

(Ω)

Current

(mA)

Output Resistance

(Ω)

10 111 101 993.5 0.010065425 10034.35

20 110 100 993.5 0.010065425 9935

40 109 99 993.5 0.010065425 9835.65

60 108 98 993.5 0.010065425 9736.3

80 107 97 993.5 0.010065425 9636.95

100 106 96 993.5 0.010065425 9537.6

200 106 96 993.5 0.010065425 9537.6

400 106 96 993.5 0.010065425 9537.6

600 106 96 993.5 0.010065425 9537.6

800 106 96 993.5 0.010065425 9537.6

1000 106 96 993.5 0.010065425 9537.6

2000 106 96 993.5 0.010065425 9537.6

4000 106 96 993.5 0.010065425 9537.6

6000 106 96 993.5 0.010065425 9537.6

8000 106 96 993.5 0.010065425 9537.6

10000 106 96 993.5 0.010065425 9537.6

20000 106 96 993.5 0.010065425 9537.6

40000 104 94 993.5 0.010065425 9338.9

60000 105 94 993.5 0.011071968 8489.909091

80000 105 93 993.5 0.01207851 7699.625

100000 105 91 993.5 0.014091595 6457.75

200000 103 80 993.5 0.023150478 3455.652174

400000 101 70 993.5 0.031202818 2243.387097

600000 101 68 993.5 0.033215903 2047.212121

800000 101 65 993.5 0.036235531 1793.819444

1000000 98 60 993.5 0.038248616 1568.684211

1500000 98 51 993.5 0.047307499 1078.053191

2000000 98 41 993.5 0.057372924 714.622807

2500000 98 35 993.5 0.063412179 551.9444444

3000000 98 29.3 993.5 0.069149472 423.7197962

Table 10: Laboratory Tabular Input Impedance

Page 30: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 30 of 33

Frequency

(Hz)

Vtest

(mV)

Vin

(mV)

Resistance

(Ω)

Current

(mA)

Output Resistance

(Ω)

10 108 20 97476 0.000902786 22153.63636

20 107 19.7 97476 0.000895605 21996.30241

40 109 19.1 97476 0.000922278 20709.58398

60 109 18.1 97476 0.000932537 19409.41254

80 113 18.5 97476 0.000969469 19082.60317

100 111 18.1 97476 0.000953055 18991.55651

200 111 17.1 97476 0.000963314 17751.22045

400 113 16.9 97476 0.000985884 17141.98127

600 109 15.7 97476 0.000957159 16402.71383

800 113 16.3 97476 0.000992039 16430.80455

1000 109 15.7 97476 0.000957159 16402.71383

2000 113 16.3 97476 0.000992039 16430.80455

4000 109 15.7 97476 0.000957159 16402.71383

6000 105 15.1 97476 0.000922278 16372.49833

8000 105 15.1 97476 0.000922278 16372.49833

10000 109 15.7 97476 0.000957159 16402.71383

20000 109 15.7 97476 0.000957159 16402.71383

40000 103 14.1 97476 0.000912019 15460.19798

60000 107 11.3 97476 0.00098178 11509.70533

80000 103 10 97476 0.000954081 10481.29032

100000 103 9.6 97476 0.000958185 10018.94647

200000 107 7.2 97476 0.001023842 7032.336673

400000 105 5.1 97476 0.001024868 4976.252252

600000 103 2.6 97476 0.001029997 2524.278884

800000 105 2.3 97476 0.001053593 2183.006816

1000000 103 1.8 97476 0.001038204 1733.762846

1500000 102 1.7 97476 0.001028971 1652.135593

2000000 101 1.6 97476 0.001019738 1569.030181

2500000 100 1.3 97476 0.001012557 1283.878419

3000000 100 1.1 97476 0.001014609 1084.16178

Table 11: Laboratory Tabular CD4007 MOSFET Output Impedance

Page 31: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 31 of 33

Laboratory Computation

(Eqn.11)

(Eqn.12)

0

1

2

3

4

5

6

1 10 100 1000 10000 100000 1000000 10000000

Gain

Volt

an

ge (

V/V

)

Frequency (Hz)

CD4007UBE MOSFET Common Source

Amplifier

CD4007UBE MOSFET Common Source Amplifier

ECGR 3155-Systems and Electronics Lab

Experiment #10 MOSFET Amplifier Input/Output

Impedances

Ethan Miller

Figure 27: CD4007UBE MOSFET Common Source Amplifier

Page 32: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 32 of 33

Conclusions:

Experiment 8:

In conclusion three different circuits were built in order to determine the operation

region of the MOSFET, the resistance between drain and source terminals and to

determine the diode characteristics inside the MOSFET. The CD4007 MOSFET found

three different regions of operation, the following operation regions were found:

saturation region, pinched off point and the ohmic/triode region. Each of the regions had

its importance to the MOSFET. The MOSFET only acted as an amplifier when the region

was found to be in the saturation region. During the ohmic region the MOSFET found an

internal variable resistance between the drain and source terminal. A change in voltage of

VGS changed the internal resistance in the MOSFET. Also found in the operation region

was the point at which VDS saturation was equaled to VDS. At this point the current IDS

was kept at a constant rate as the VDS were increased into the saturation region.

Found in the last circuit built (diode connected MOSFET) was found to act as a

diode since the gate terminal was connected to the drain terminal. As the gate and the

source were connected to each other the MOSFET was kept in the saturation region and

never entered into ohmic region.

Experiment 9:

In the development of the three different MOSFET amplifier circuits the common

drain and common gate had similar midband voltage gain as well as low and high cutoff

frequencies. An explanation for this result was the fact that where the input voltage was

positioned in each circuit ended up equaling the same amount which was found to be

VGS. The low cutoff frequency was determined by the external capacitors and the high

cutoff frequency was determined by the internal capacitors or distance between the two

diodes which formed a MOSFET. The common drain MOSFET amplifier had a

significant drop in midband voltage gain and a high bandwidth in compared to the other

configurations. This amplifier resulted in an approximate 1 volt peak to peak midband

voltage gain and a 1249700 hertz bandwidth.

Experiment 10:

In conclusion three circuits were built in order to find the midband voltage gain,

input and output impedances of a MOSFET amplifier. The midband voltage gain and DC

voltages resulted in a similar value as in experiment 9. A different chip which could have

had unusual current characteristics may have caused such a high value of voltage gain.

The input and output impedances were found to have close to the values found in P-Spice

and hand calculations. The output impedance was found to have a high value of

impedance due to the tolerance of resisters and the current flowing through the MOSFET.

Page 33: MOSFET,MOSFET Amplifier Configuration,MOSFET Amplifier Inputoutput

Page 33 of 33

List of Attachments:

CD4007UBE Data Sheet

References: [8] Lab Handout “MOSFET”

[9] Lab Handout “MOSFET Amplifier Configuration”

[10] Lab Handout “MOSFET Amplifier Input/Output”

[1] "Electrial Network," 18 April 2011. [Online]. Available:

http://en.wikipedia.org/wiki/Electrical_network. [Accessed 21 Apirl 2011].

[2] "Chapter 8 MOSFET," West Virginia Univercity Department of Electrical and Computer

Engineering , 2 Feburay 2014. [Online]. Available:

http://www.csee.wvu.edu/digital/book/chapters/MOS2.pdf. [Accessed 9 July 2014].

[3] E. Project, "Power Supply For Intergrated Circuit," ElectronicsTutorials, 12 May 2014.

[Online]. Available: http://electronicsproject.org/power-supply-for-integrated-circuit-ics-and-

microprocessor/. [Accessed 3 June 2014].

[4] A. S. Sedra and K. C. Smith, Microelectronic Circuits, sixth ed., New York: Oxford

University Press, 2010.

[5] J. W. Nilsson and A. R. Susan, Electric Circuits, 9th ed., Saddle River: Pearson Prentice Hall,

2011.

This report was submitted in compliance with UNCC POLICY STATEMENT #105

THE CODE OF STUDENT ACADEMIC INTEGRITY, Revised August 24, 2008

(http://www.legal.uncc.edu/policies/ps-105.html) (ECM).