What makes a device ohmic

The properties of non-ohmic conductors also vary according to the change in temperature. The examples of non-ohmic conductors are diodes, transistors, thyristors, electrolyte, semiconductors, etc. Both the conductors, whether ohmic and non-ohmic, have their specific functions and purposes.

However, ohmic conductors may lose their properties when operated on different ranges so it becomes really important to study their properties before application.

In the ohmic conductors, the current and voltage are directly proportional to each other, that is, there is a linear relationship between current and voltage. The diode does not have a straight line as a VIcurve. An ohmic conductor is anything that conducts electricity directly proportional to the applied voltage. So examples are a copper wire, a resistor, and uniformly doped silicon.

A non- Ohmic device is one that does not have a constant resistance. A light bulb is a simple example; the filament undergoes huge changes in temperature when current passes through it. Therefore, the resistance of the filament is not constant, rather, it increases with increased current.

Non ohmic resistors are those which do not obey ohms law. Non-Ohmic conductors do not follow Ohms law and have their own characteristics. There are a number of examples of non-Ohmic conductors; including bulb filaments and semiconductors like diodes and transistors. The device is said to be non-Ohmic. The high voltages create heat removing a resistor from its ohmic region.

The light bulb is non-ohmic because the filament burns at high temperatures. LEDs are non-ohmic because they are semiconductors. A light bulb is a common example of a non-ohmic conductor. Other examples of non-ohmic conductors are diodes and transistors. A non- Ohmic device is one that does not have a constant resistance. A light bulb is a simple example; the filament undergoes huge changes in temperature when current passes through it. It is not a true resistance since it is not constant but, instead, varies with the operating point of the transistor as can be seen by the formula.

No, a lightbulb is not an ohmic resistor. This and the spool of wire experiment, were the only devices that showed Ohmic graphs, meaning that they were linear. To analyse the behaviour of a capacitor requires consideration of the rate of change of voltage potential and there is a phase difference between voltage changes and subsequent changes in current.

From the schematic above we can see that a battery has capacitive and resistive qualities. The battery will also contain inductive qualities when the terminals are taken into account. As the temperature increases, resistance of the filament also increases. Semiconductor diode: The semiconductor diode is one of the most obvious non-Ohmic devices that is available. The basic diode consists of a junction between P-type and N-type material, and the basic action is that only allows current through in one direction.

The ideal diode would have no resistance in the forward direction and infinite resistance in the reverse direction. This alone would make it a non-Ohmic conductor, but in reality the situation is more complicated. In the forward direction, as the potential difference across the device is increased from zero initially little current flows because the current carriers in the PN junction need to have sufficient energy to traverse the junction.

As the potential, more current flows as more electrons have sufficient energy, but the current voltage relationship is far from Ohmic. In the reverse direction, as the potential difference is increased across the diode very little current flows across the junction, although it does increase slowly. However a point is reached where breakdown occurs and current flows. The overall characteristic of a PN junction diode is far from Ohmic as seen in the characteristic below.

The PN junction diode is the most basic form of semiconductor device. Consisting of a single junction between P-type and N-type material it is able to act as a rectifier allowing current to pass in only one direction. Read more about PN Junction Diode. Most semiconductor devices: The semiconductor diode is a specific example of a semiconductor device that is often encountered within electronic circuits. However it is not the only example of a non-Ohmic conductor made from semiconductor material.

Most other semiconductor device are good examples of non-Ohmic responses. It is not possible to detail each type, but it is probably sufficient to mention that they are non-Ohmic in many if not most of the aspects of their operation. These are just three examples of non-Ohmic conductors and components.