Transformer (transformer) is the electrical / electronics that function to move energy (power) power from input to output or from the primary to the secondary side. The transfer of power from primary to secondary voltage is accompanied by changes either up or down.

There are two types of transformer Raising the voltage transformer (stepup transformers) and lowering the voltage transformer (stepdown transformer).

If the primary voltage is smaller than the secondary voltage, so-called stepup transformer. But if the primary voltage is greater than the secondary voltage, so-called stepdown transformer.At each transformer has primary windings named input and output is called the secondary winding. Has an iron core transformer for low frequency and high frequency ferrite core or some that did not have a core (air core).

When the primary winding given alternating current (AC), the primary windings will be the direction of the magnetic field also magnitnya commute. This magnetic field will induce the secondary winding and secondary winding flows resulted in an alternating current (AC). Suppose the primary coil current flows berfasa positive (+), then the current flowing in the secondary coil berfasa negative (-). Because the current through primary digulungan back and forth, then on the roll sekunderpun flowing alternating current. The amount of charge in the primary winding with the power supplied to the secondary winding. So Pp = Ps or Up.Ip = Us.Is

Where:

**Pp = primary power in watts**

**Ps = power in watts secondary**

**Up = primary voltage in volts**

**Us = secondary voltage in volts**

**Ip = Primary Current in ampere**

**Is = secondary current in amperes**

**Example:**

A power transformer is connected to the net voltage 220 V, current flowing in primary winding 0.2 amperes. If the secondary voltage of 12 V. Calculate the amount of secondary flow.

**Completion:**

Up.Ip = Us.Is 220.0,2 = 12. Is Is Is = 44/12 = 3.66 amps

Comparison of transformation:

In general, the number of primary winding is not equal to the number of secondary winding. For stepup transformer primary winding number fewer than the number of secondary winding, contrary to stepdown transformer primary winding amount more than the number of secondary winding. Number of primary winding and secondary winding number shows the amount of voltage primary and secondary tgangan magnitude. The greater the voltage the more the windings. Thus the number of winding is directly proportional to the voltage-enter the respective sides. If the secondary winding and primary winding = Ns = Np, then the ratio of primary winding and secondary winding is called the transformation ratio and expressed as T = Np / Ns. In the transformer equation applies: Up / Us = Np / Ns or T = Up / Us

**Example:**

A power transformer primary voltage of 220 V, the secondary voltage of 30 V. Number of primary winding 1100 wrap. Calculate the number of secondary winding.

**Completion:**

Up / Us = Np / Ns = 220/30 = 7.33 1100/Ns 1100/Ns

Ns = 1100 / 7.33 = 150.06 Ns wrap

In the technique known to a variety of electronic transformers, for both high frequency and low frequency. Examples of transformer for high frequency oscillator transformer, transformer intermediate frequency (IF), transformer spull antenna (tuner). While the transformer used for low frequency input transformer, output transformer, transformer filter (choke).