BioMedical Admissions Test (BMAT) 2025 – 400 Free Practice Questions to Pass the Exam

The function of a diode in electronic circuits is to allow current to flow in one direction only. This unidirectional behavior is fundamental to how a diode operates and is primarily due to its construction, which typically consists of a p-n junction. In this junction, one side (the p-type) has an abundance of positive charge carriers (holes), while the other side (the n-type) has an abundance of negative charge carriers (electrons).

When a voltage is applied in the forward direction (positive voltage to the p-side and negative to the n-side), the diode becomes conductive, allowing current to flow through it. Conversely, when the voltage is reversed, the diode prevents current from flowing, effectively blocking it. This property is essential in various applications within circuits, such as rectification, where alternating current (AC) is converted to direct current (DC).

In summary, the diode’s ability to control the direction of current flow is what makes it indispensable in many electronic applications, distinguishing it from components that perform other functions, such as energy storage or current measurement.