Current–voltage characteristic - Wikipedia
A device that exhibits significant self-inductance is called an inductor, and given . on the physical characteristics of the solenoid, consistent with its definition. Describe current-voltage relationship in the RL circuit and calculate energy that. Chapter 6 • Electronic Circuit Design Using Capacitors and Inductors. 6–4. ECE Electronic y3y3games.info://y3y3games.info Fixed Capacitor The fundamental terminal relationship involves calculus: () or in words, the. Unlike the resistor which dissipates energy, ideal capacitors and inductors store energy The current-voltage relationship of a capacitor is dv i C dt. = ().
The I—V curve of an electrical component can be measured with an instrument called a curve tracer. The transconductance and Early voltage of a transistor are examples of parameters traditionally measured from the device's I—V curve.
Types of I—V curves[ edit ] The shape of an electrical component's characteristic curve reveals much about its operating properties.
I—V curves of different devices can be grouped into categories: The quadrants of the I—V plane. Power sources have curves passing through the red regions. Devices which have I—V curves which are limited to the first and third quadrants of the I—V plane, passing through the originare passive components loadsthat consume electric power from the circuit. Examples are resistors and electric motors.
Conventional current always flows through these devices in the direction of the electric fieldfrom the positive voltage terminal to the negative, so the charges lose potential energy in the device, which is converted to heat or some other form of energy.
In contrast, devices with I—V curves which pass through the second or fourth quadrants are active componentspower sourceswhich can produce electric power. Examples are batteries and generators.
Energy Stored in an Inductor
When it is operating in the second or fourth quadrant, current is forced to flow through the device from the negative to the positive voltage terminal, against the opposing force of the electric field, so the electric charges are gaining potential energy.
Thus the device is converting some other form of energy into electric energy. A straight line through the origin represents a linear circuit element, while a curved line represents a nonlinear element.
For example, resistors, capacitors, and inductors are linear, while diodes and transistors are nonlinear. An I—V curve which is a straight line through the origin with positive slope represents a linear or ohmic resistor, the most common type of resistance encountered in circuits.
It obeys Ohm's law ; the current is proportional to the applied voltage over a wide range. Its resistanceequal to the reciprocal of the slope of the line, is constant.
A curved I—V line represents a nonlinear resistance, such as a diode. In this type the resistance varies with the applied voltage or current. Negative resistance vs positive resistance: An I—V curve which is nonmonotonic having peaks and valleys represents a device which has negative resistance.
Regions of the curve which have a negative slope declining to the right represent operating regions where the device has negative differential resistancewhile regions of positive slope represent positive differential resistance. Negative resistance devices can be used to make amplifiers and oscillators.
Tunnel diodes and Gunn diodes are examples of components that have negative resistance.
Try wikipedia for more on resistors and for the resistor color codes. The relationship between the current through a conductor with resistance and the voltage across the same conductor is described by Ohm's law: The power dissipated by the resistor is equal to the voltage multiplied by the current: If I is measured in amps and V in volts, then the power P is in watts. The potential on the straight side with the plus sign should always be higher than the potential on the curved side.
Notice that the capacitor on the far right is polarized; the negative terminal is marked on the can with white negative signs. The polarization is also indicated by the length of the leads: A capacitor is a device that stores electric charges.
Resistors (Ohm's Law), Capacitors, and Inductors
The current through a capacitor can be changed instantly, but it takes time to change the voltage across a capacitor. The unit of measurement for the capacitance of a capacitor is the farad, which is equal to 1 coulomb per volt. The charge qvoltage vand capacitance C of a capacitor are related as follows: Differentiating both sides with respect to time gives: Rearranging and then integrating with respect to time give: If we assume that the charge, voltage, and current of the capacitor are zero atour equation reduces to: The energy stored in a capacitor in joules is given by the equation:
- Current–voltage characteristic
- Inductor equations