# Linear Regulator in Open Loop DC Operation

The goal of this lab is to investigate the properties of a MOSFET in DC operation, when it works as a pass device in linear regulators. First, we review the equations describing the behavior of a MOSFET in DC operation, and discuss the impact of the gate-to-source voltage on the operating point. Next, we predict the MOSFET operating region and calculate the power losses and temperature under different conditions. Then, we simulate the MOSFET using its physical model. Finally, we perform lab experiments to estimate the real value of MOSFET parameters and compare their impact on the accuracy of theoretical and simulation predictions.
##### by Dr. Nicola Femia | University of Salerno, and Texas Instruments

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This is lab 1 of 12 in the course, Power Electronics.

### LEARNING OBJECTIVES

After completing this lab, students will be able to:
1. Given the parameters of a MOSFET, a source voltage and a load resistance, calculate the gate driver voltage required to achieve a desired output voltage, you will determine the MOSFET operating region and calculate its drain-to-source voltage and current, power losses and junction temperature, with specified units and decimal digits, by applying the appropriate MOSFET equations
2. Given the parameters of a MOSFET, a source voltage, and a load resistance, determine the gate driver voltage required to achieve a desired output voltage by simulating the MOSFET operation, you will determine the MOSFET operating region and calculate its drain-to-source voltage and current, power losses and junction temperature, with specified units and decimal digits, and you will determine the accuracy of theoretical predictions.
3. Given a real MOSFET, a DC power supply, a load resistor of given resistance, and a function generator, set experimentally the MOSFET gate driver voltage allowing to achieve a desired output voltage, you will record the measurement, with specified units and decimal digits, you will compare the measured values with the simulations, and you will determine the accuracy of simulations.

### REQUIRED SKILLS

• Basic proficiency using Multisim Live
• Basic proficiency using ELVIS III Instruments
• Basic proficiency in circuits and analog electronics

### NI ELVIS III

Engineering laboratory solution for project-based learning that combines instrumentation and embedded design with a web-driven experience, delivering a greater understanding of engineering fundamentals and system design.

### Multisim Live

Multisim Live is an online, touch-optimized component of Multisim, so students can design and simulate their circuits anywhere, anytime, on any device.

### TI Power Electronics Board for NI ELVIS III

Application board for NI ELVIS III which provides a hands-on approach to power electronics using functional blocks and TI circuits to understand each component in a power electronics system.