Transcript

ECE 2300

Electronics Circuits and

Electronics Devices Laboratory

Gregg Chapman

Laboratory 7Transistors

Background

• Bipolar Junction Transistors

• MOSFET Transistors

Screencast: 0:10

Bipolar Junction Transistors

Screencast: 0:20

MOSFET Transistors

Screencast: 1:53

Circuits

1. Constant Current Source

2. Constant Current Sink

3. MOSFET Power Switch

Screencast: 3:17

Lab Supplies• Resistors

1 7.5 Ohm, 6.5 Watt (From Lab Monitors)

1 150 Ohm

1 499 Ohm

2 20.0 KOhm

1 100 Kohm

• Transistors

1 2N5088G

1 2N5087G

1 2N7000TA

1 NTP2955G

Screencast: 3:33

Lab Supplies• Breadboard

• Digital-Multi-meter

• Power Supply

• Banana to Banana, black (1)

• Banana to Banana, red (1)

• Banana to Mini-grabber, black (2)

• Banana to Mini-grabber, red (2)

• Banana to Mini-grabber, green (1)

Screencast: 4:00

Test Set-up 1

• Power Supply• Program the +25V supply for +12 Volts• Use the following banana to mini-grabber color codes

• Red: +12V• Black: Ground

• Digital Multimeter• Use banana to mini-grabbers ( Red, Black)

Screencast: 4:21

Constant Current Source

DMM goes here

Screencast: 5:00

Transistor Pin-outs

Screencast: 7:33

Constant Current Sink

DMM goes here

Screencast: 7:56

Transistor Pin-outs

Screencast: 8:36

Calculations and Measurements• Circuit 1 and 2 (BJTs)

• Using the base voltage and the emitter resistor, calculate the emitter current. Assume that V

BE is 0.65 V.

•Measure collector currents

CircuitCalculatedValue (mA)

Measured Value (mA)

NPN Current Sink

Current Sink Results

CircuitCalculatedValue (mA)

Measured Value (mA)

PNP Current Source

Current Source Results

Screencast: 8:48

Test Set-up 2

• Power Supply• Connect the two black commons together using the black banana to banana cable• Program the +6V supply for +5 Volts.• Program the +25V supply for +12 Volts• Use the following banana to mini-grabber color codes

• Red: +12V• Black: Ground• Green: +5V

• Digital Multimeter• Use banana to mini-grabbers ( Red, Black)

Screencast: 8:58

Screencast: 9:24

MOSFET Power Switch

DMM goes here

Screencast: 9:50

Transistor Pin-outs

Screencast: 11:16

Transistor Pin-outs

Screencast: 11:43

Measurements• Circuits 1 & 2 ( Current source and sink)

• Measure collector currents

• Circuit 3• Measure source to drain current P channel fully on (N channel G at 5 V)• Decrease N channel gate voltage and document the minimum on voltage for the circuit ( S-to-D current should be greater than 90% of full on value)

Circuit Value

P Channel S-to-D CurrentN Channel On Voltage

MOSFET Power Switch

Screencast: 11:56

Lab 7 Results

Circuit Value

P Channel S-to-D Current

N Channel On Voltage

MOSFET Power Switch

CircuitModified Resistor

Value (Top R in Base Voltage

Divider)

CalculatedVB

CalculatedVE

CalculatedValue (mA)

Measured Value (mA)

PNP Current Source

CircuitModified Resistor

Value (Bottom R in Base Voltage Divider)

CalculatedVB

CalculatedVE

CalculatedValue (mA)

Measured Value (mA)

NPN Current Source

Current Source Results (2nd Circuit in Demo, 1st in Screencast)

Current Sink Results (1st Circuit in Demo, 2nd in Screencast)

NTP2955 GDS

2N7000 SGD

2N5087 EBC

2N5088 EBC

ASSUME β = 500

Screencast: 12:40

Lab 7 Schematics

MOSFET Power Switch

DMM goes here

NTP2955

Constant Current Sink

DMM goes here

ConstantCurrent Source

DMM goes here


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