In general, when diffusion facilitates the subsequent movement of electrons from the n-type region, they begin to fill the holes within the p-type region. Diode Functionality and Operation Continued Lastly, if you apply a significant reverse voltage, it will cause a comprehensive electronic breakdown of the diode, thus allowing the current to flow in the opposite direction through the diode. Also, the reverse-bias voltage will produce a small amount of current through the diode, and it is called leakage current, but typically it is negligible. Furthermore, the minimum threshold voltage in most cases for diodes is approximately 0.7 volts. Note: Keep in mind that for proper functionality, a diode requires a minimum threshold voltage to surmount the depletion region.
Furthermore, the area that exists between the two elements is called the depletion region. Also, the merging of these two types of materials forms what we call a p-n junction. However, diode functionality is only possible, of course, when we merge the two types (P, N) of materials. Overall, it is the variances between the two materials and their subsequent synergy over extremely short distances (< millimeter) that facilitate diode operation. Moreover, the positive and negative regions of the diode are also called its anode (P) and cathode (N). Furthermore, it is also possible to dope a semiconductor to promote an excess of holes to easily absorb those electrons as well, and we refer to this as the p-type or positive region. You can dope a semiconductor with materials to facilitate an excess of easily displaced electrons, which we refer to as an n-type or negative region. In general, the proper operation of a diode requires another essential element or process called doping. P-n junctions are an essential part of a photovoltaic cell operation as well.
Technologically speaking, we refer to a semiconductor diode as a p-n junction. Diode operation concerns the flow of negative charges (electrons) and positive charges (holes). The detailed process of a diode can be somewhat challenging to understand since it involves an understanding of quantum mechanics. Zener diode placement knowledge can make or break a design.Įarlier, I provided a more simplified explanation of standard diode operation. There are a variety of other uses for this characteristic, including electronic signal control. Furthermore, this particular characteristic is beneficial for changing alternating current (AC) into direct current (DC). However, the voltage present across a diode during reverse biasing does not produce any significant flow of current. In a standard diode, forward biasing occurs when the voltage across a diode permits the natural flow of current, whereas reverse biasing denotes a voltage across the diode in the opposite direction. Also, when in reverse bias, a standard PN junction diode will typically inhibit or block the flow of current, almost like an electronic version of a check valve. However, when the voltage moves in the reverse direction, we refer to this orientation as reverse bias. In summary, a diode typically conducts current in one direction, and the voltage they apply follows a described forward biasing orientation. Furthermore, with biasing, resides the two types of biasing, forward bias and reverse bias.Īs I am sure you are aware, a diode (PN junction) functions much like a one-way highway since it allows the flow of current more easily in one direction than the other. Although this is a simplified version of the answer, it is still fundamentally correct. In electronics, we define bias or biasing as a method of establishing a set of currents or voltages at different points of an electronic circuit to establish proper operating conditions within an electronic component. What is Diode Bias or Biasing?īefore we compare the two types of bias, first, I will discuss their individual characteristics. Moreover, the need for a particular functionality is the predominant driving force when choosing a device or process in the field of electronics.
There are times when a choice of one device or method is about a need or function. However, there is one thing that has not and that is the competitiveness of the computer manufacturers. So, it is safe to say that computer technology has evolved. Now, fast forward to the present day, and my laptop utilizes 100,000 times that amount in RAM alone. There I was with an impressive 64, wait for it, kilobytes of raw processing power. Anyway, at the time, I was the envy of every fellow geek, nerd, and teacher at my school. Since the day my mother surprised me with the first home computer for Christmas back in, well, let's just say a long time ago, I've been intrigued by the technology.