Mosfet & BJT

  

BJTs and MOSFETs are transistors and are made of semiconductors capable of producing massive changes in an electrical output signal in response to very few shifts in the input signals they receive. Because of their property, these transistors may serve either as amplifiers or switches in electronic circuits. The first transistor was commercially available for purchase in the year 1950, and it is widely acknowledged as being among the most significant discoveries of the 20th century. The technology is undergoing rapid development, and many distinct types of transistors have already been made available. The BJT, or bipolar junction transistor, was the first form of transistor ever created, and later on, another type of transistor called a MOSFET, or metal-oxide-semiconductor field-effect transistor, was developed. This article explains the primary distinction between BJTs and MOSFETs, which may help readers get a deeper comprehension of the aforementioned idea.

 

In the days gone by, vacuum tubes were replaced by a form of semiconductor device known as a bipolar junction transistor. This particular type of device is still in use today. The bipolar junction transistor (BJT) is a current-controlled device, which means that the output voltage at either the base terminal or the emitter terminal is determined by the current flowing through the base terminal. The amount of current flowing through a BJT transistor's base terminal is the primary factor that decides how the device functions. This particular transistor has three terminals, which are referred to as the emitter, the base, and the collector. A BJT is a silicon piece that has been cut into three distinct areas and two distinct connections. The two areas are referred to as the P-junction and the N-junction, respectively.

 

MOSFET is a FET (Field Effect Transistor) that has three terminals the source, and gate. And drain. Here, gate voltage controls drain current, and it is voltage controlled device. 

 

These transistors come in P-channel, N-channel, enhancement, and depletion modes. Source and Drain terminals for N-channel MOSFETs are N-type semiconductors. Metal oxide separates the gate terminal from the source and drain terminals. This transistor's shielding reduces power consumption. In digital CMOS logic, this transistor is used to lower power consumption by combining p and n channel MOSFETs.

 

The MOSFET is a metal oxide semiconductor field-effect transistor, while the BJT is referred to as a bipolar junction transistor. Both a BJT and a MOSFET have three terminals, however, the BJTs are called the base, the emitter, and the collector. The MOSFET's terminals are called the source, the drain, and the gate. BJTs are put to use in applications that need low current, whereas MOSFETs are put to use in applications that require high power. MOSFETs are seen as being employed in analog and digital circuits at a frequency that is considered to be higher than that of BJTS. The operation of a BJT is determined by the current flowing through its base terminal, while the operation of a MOSFET is determined by the voltage flowing through its oxide-insulated gate electrode. A device that controls current is called a BJT, whereas a device that controls voltage is called a MOSFET.

 

Various people have different responses either to selecting BJT or MOSFET because they used them in different contexts. For instance, BJTs perform better in applications that need low current, but MOSFETs perform better in applications that require high current. To choose the transistor that is most suited to your project, you must first conduct an accurate analysis of the primary characteristics of your project, such as the available budget, the needed switching speed, the maximum voltage, and the current ratings of the project.