Differences
This shows you the differences between two versions of the page.
| Both sides previous revisionPrevious revisionNext revision | Previous revisionNext revisionBoth sides next revision |
| university:courses:electronics:electronics-lab-11 [07 Dec 2018 13:40] – [Discussion:] Antoniu Miclaus | university:courses:electronics:electronics-lab-11 [12 Jul 2019 13:37] – [Activity 11. The Emitter follower (BJT)] Pop Andreea |
|---|
| ====== Activity 11. The Emitter follower (BJT) ====== | ====== Activity: The Emitter follower (BJT) ====== |
| |
| ===== Objective: ===== | ===== Objective: ===== |
| The concept in this circuit is that R<sub>2</sub> acts as current sense resistor. When the load current times R<sub>2</sub>, the sense voltage, reaches about 0.6 (for silicon transistors ) Q<sub>2</sub> begins to conduct and increases current in R<sub>1</sub> which limits the base drive to Q<sub>1</sub>reducing its output current. The maximum current from the circuit is reached when I<sub>L</sub>*R<sub>2</sub> = 0.6. This circuit can be used to protect amplifiers (including push pull amplifiers.), power supplies and other circuits; or it can be used as a constant current circuit. This is not a precision circuit; however it is a simple and effective circuit. | The concept in this circuit is that R<sub>2</sub> acts as current sense resistor. When the load current times R<sub>2</sub>, the sense voltage, reaches about 0.6 (for silicon transistors ) Q<sub>2</sub> begins to conduct and increases current in R<sub>1</sub> which limits the base drive to Q<sub>1</sub>reducing its output current. The maximum current from the circuit is reached when I<sub>L</sub>*R<sub>2</sub> = 0.6. This circuit can be used to protect amplifiers (including push pull amplifiers.), power supplies and other circuits; or it can be used as a constant current circuit. This is not a precision circuit; however it is a simple and effective circuit. |
| |
| | <WRAP round download> |
| **Resources:** | **Resources:** |
| * Fritzing files: [[ https://minhaskamal.github.io/DownGit/#/home?url=https://github.com/analogdevicesinc/education_tools/tree/master/m2k/fritzing/bjt_emitter_ff_bb | bjt_emitter_ff_bb]] | * Fritzing files: [[ https://minhaskamal.github.io/DownGit/#/home?url=https://github.com/analogdevicesinc/education_tools/tree/master/m2k/fritzing/bjt_emitter_ff_bb | bjt_emitter_ff_bb]] |
| | * LTspice files: [[ https://minhaskamal.github.io/DownGit/#/home?url=https://github.com/analogdevicesinc/education_tools/tree/master/m2k/ltspice/bjt_emitter_ff_ltspice | bjt_emitter_ff_ltspice]] |
| | </WRAP> |
| |
| **Return to Lab Activity [[university:courses:electronics:labs|Table of Contents]]** | **Return to Lab Activity [[university:courses:electronics:labs|Table of Contents]]** |
| |
| |
