transformer
trans·form·er 
- An example of a transformer is a fictional creature that changes from a person into a dog.
- An example of a transformer is a device that uses electromagnetic induction.
transformer
- a person or thing that transforms
- Elec. a device consisting essentially of two or more coils of insulated wire, that transfers alternating-current energy by electromagnetic induction from one winding to another at the same frequency but usually with changed voltage and current values
transformer
noun
- One that transforms: a transformer of recruits into soldiers.
- A device used to transfer electric energy from one circuit to another, especially a pair of multiply wound, inductively coupled wire coils that effect such a transfer with a change in voltage, current, phase, or other electric characteristic.
transformer
iron-core transformer
transformer
(plural transformers)
- Something that transforms, changing its own or another thing's shape.
- (electrical engineering) A static device that transfers electric energy from one circuit to another by magnetic coupling. Their main use is to transfer energy between different voltage levels, which allows choosing most appropriate voltage for power generation, transmission and distribution separately.
transform + -er
transformer - Computer Definition
A static device that couples two circuits for the purpose of transferring alternating current (AC) from one circuit to another by electromagnetic induction. The current remains at the same frequency, but may change in voltage, phase, or impedance values.A transformer comprises two or more wire coils, or windings, but no moving parts.The voltage induced in a coil on a transformer is proportional to the number of turns around the core. See also AC, frequency, impedance, inductance, phase, and voltage.
A device that is mostly used to change the voltage in an alternating current (AC); however, it can also be used to maintain the same voltage but act as an electrical isolator. The most common type is the laminated core transformer found in power supplies. Made of steel laminations wrapped with two coils of wire, the ratio of windings between the "primary" input coil and the "secondary" output coil determines the voltage change. For example, if the primary has 1,000 windings and the secondary 100, an input of 120 volts is changed to 12v. Via ElectroMagnetic Induction There are numerous transformer architectures, and they span the size gamut. Small ones are used in the myriad black boxes that plug into the wall and create low DC voltage for every electronic gadget, while transformers weighing tons are used to transmit 50,000 volts of AC over the nation's power grid. However, they all work via electromagnetic induction. The changing current in the primary coil induces a voltage across the secondary coil. Switching Power Supplies The greater the current needed to power the device, the thicker the wire in the coils and the larger the transformer. However, if a high frequency is used, the number of windings can be reduced to make the transformer small. To accomplish this, the incoming voltage is converted to DC (rectified), and a high-frequency oscillator pulses a transistor that passes the rectified voltage as square waves into a "pulse transformer." The on/off DC pulses cause the changing current in the primary coil just the same as AC does. This square wave generation turns a power supply into a "switching power supply." See power adapter, power supply and wall wart.
