Electronic Transformers FAQ

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  1. What are the types of electronic transformers?
  2. What are the sub-types of electronic transformers?
  3. What is the basic structure and/or construction style of electronic transformers?
  4. How are electronic transformers mounted and what are the electrical terminations?
  5. What are the uses of electronic transformers?
  6. Do electronic transformers have any characteristics common to all electronic  transformers?
  7. What is the theory of operation among the different types of electronic transformers?

What are the types of electronic transformers?

Power transformers, pulse transformers, instrument transformers, current transformers, switching, or switch mode, power transformers, inverter transformers, signal transformers, step-up transformers, step-down transformers, impedance matching transformers, high voltage transformers and saturable transformers.

What are the sub-types of electronic transformers?

Types of switching transformers include ( but not limited to ) flyback, “feed forward” converter ( also called “buck” ), and boost. Gate drive transformers and trigger transformers are types of pulse transformers ( depending on who you talk to). The “feed forward” type includes a “push-pull center-tap” and a “half bridge” configuration. It becomes apparent from the preceding type designations that the type designation of an electronic transformer is determined by its intended application. To learn more about a particular type, click on one of the available links for electronic transformer types.

What is the basic structure and/or construction style of electronic transformers?

Many current transformers are wound on toroidal cores; hence, the transformer is referred to as a toroidal current transformer. Many transformer coils are wound on bobbins (spools) or tubes. The transformer core is inserted into and around the coil. These transformers may be referred to as “bobbin wound” or “tube wound” structures. There are many core shapes available: E, E-I, U, U-I, Pot, RM, PQ, EP, EFD, and others.

How are electronic transformers mounted and what are the electrical terminations?

Transformers mounted on printed circuit boards may be “pin-thru” or “surface mount”. Transformer windings are terminated to bobbin pins or surface mount pads. The pins or pads are then soldered to the printed circuit board. Some transformers have lead wires. These wires are often referred to as “flying leads”.

What are the uses of electronic transformers?

Electronic transformers supply power, transmit signals, establish voltage isolation between circuits, sense voltage and current levels, modify voltage and current levels, provide impedance matching and filter. Lightly loaded transformers may perform some “inductor-like” functions, such as storing energy and limiting current flow.

Do electronic transformers have any characteristics common to all electronic transformers?

Not really. Most electronic transformers can easily be held in your hand, even in a child’s hand, but there are some too large to hold. Due to ever-higher operating frequencies, more electronic transformers are being made from ferrite core materials, but some specialized applications use other core materials.

What is the theory of operation among the different types of electronic transformers?

The theory of operation does not differ. Electrical functions are usually similar, but design characteristics can differ in certain ways. Some examples are: unipolar versus bipolar core utilization, saturating or not saturating, degree of energy storage, regulation, and transformer impedance.