Transformers and inductors are passive magnetic devices that are used in a wide variety of applications, from RF to providing power to homes and offices. Power, signal, isolation, audio, pulse, are a few typical applications of transformers. The size of these devices can vary from a large transformer weighing tons, to a mini-transformer weighing only a few grams.
Transformers are often the largest, heaviest and costliest components of a circuit. Since the geometry of a magnetic circuit is three-dimensional, it is difficult to reduce its size. In today’s market there is a big push to make electronics devices smaller and smaller and Pico Electronics has achieved, and maintained, its leadership in miniaturization of these magnetic devices.
Audio transformers are typically used at frequencies of 20 Hz to 20 kHz. A transformer that’s used beyond the upper limit is referred to as a wideband transformer. A wideband transformer is used in such applications as video transmission, high fidelity audio, communications equipment and feedback circuits. Because of their wide variety, Pico Electronics’ audio transformers are widely used in headsets used by the military.
One common application of an audio transformer is impedance matching. For example, Pico Electronics’ ultra-miniature surface mount transformer 70445 has a turns ratio of 25:1 and has a maximum allowed primary voltage of 35Vrms. As stated earlier, in order to maintain maximum power transfer, primary and secondary circuit impedances must match. With 16 Ohm load on secondary, primary impedance will measure 10,000 Ohms and will be relatively flat over the frequency range. In this case it is 400 Hz to 250 kHz. It is calculated as square of the turns ratio (16 Ohms* 25^2=10000). The primary open circuit inductance will vary with frequency along with open circuit impedance. This ensures that the primary and secondary loads are matched.
With its proprietary core design, Pico Electronics has achieved miniaturization of audio and wideband transformers. Pico’s new RPS series transformers are electrically the same as the 76, 77, 82 and 83 series transformers. However they are packaged differently, they are round. This saves customers even more space, as they take about 22% less space than their square counterpart. Pico Electronics continues to improve size reduction while improving electrical characteristics.
Pulse transformers, as the name implies, transform video pulses and are also used in communications for data transfer. Although similar to wideband transformers, they differ in the way they are specified and designed. The major use of a pulse transformer is radar. These can also be used in an inverter where, if the control is on the secondary side of the gate drive, pulse information needs to be fed on the primary side. Pico Electronics’ data bus and MIL – STD – 1553 transformers have low inter winding capacitance, which reduces overshoot and ringing.
Pico also has a wide variety of 400 Hz power transformers from less than 1 Watt up to 50 Watts in surface mount and thru-hole packages. Pico Electronics’ transformers are unique in that they are lower profile and are able to handle more power in a small outline. And Pico Electronics’ special potting process enables its transformers to operate in rugged environments. From below sea level to aerospace applications, Pico Electronics’ transformers and inductors are continually being used for research and defense.
Inductors, on the other hand, are energy storage devices. Unlike transformers, inductors have a single winding. A typical application of an inductor is part of a filter, as a common mode and a differential mode. They are used in power supplies as part of the output filter. Pico Electronics’ lines of differential / power inductors are able to withstand high current transients. Their plug-in inductors are manufactured and tested to MIL – PRF – 27 / 356. Power inductors are also available in axial leads.
A common mode filter essentially filters out common mode noise that’s generated between plus and minus of the power lines. Pico Electronics’ HCM series common mode inductors provide customers with an effective way of reducing common mode noise. These inductors are high current small package inductors. To achieve this combination, Pico Electronics makes use of special materials. When it comes to reducing total EMI noise, differential, and common mode, Pico Electronics can be the one stop source for customers’ designs.
Finding the right component that meets the electrical, as well as mechanical criteria, for those that are challenged with reducing space on the PCB, Pico Electronics is the leader in low profile, ultra-miniature magnetics. Pico Electronics’ transformers and inductors are manufactured to MIL – PRF – 27, Grade 5, Class S. Also, Pico Electronics is an approved QPL source. Pico Electronics’ customer base is wide ranging, from small companies with less than ten employees to mega companies like Raytheon, BAE and UTC. With its strong commitment to customer satisfaction and support, Pico Electronics has been providing customers with high quality, space-saving solutions since 1967.
Visit Pico Electronics at www.picoelectronics.com.