Power Transformers

These standard transformers are available with optional tin-lead or tin-silver-copper terminations, which can improve the solder fillet and ensure an exceptionally reliable solder joint. They may also be available with an extended temperature range.

Flyback transformers are the most popular choice for cost-effective, high-efficiency isolated power supply designs up to approximately 120 Watts. They provide circuit isolation, the potential for multiple outputs and the possibility of positive or negative output voltages. They can also be regulated over a wide range of input voltages and load conditions. Because energy is stored in the transformer, the flyback topology does not require a separate output filter inductor like the other isolated topologies. This reduces the component count and simplifies the circuit requirements.

Current transformers accurately sense and measure current flow in power supply circuits in a non-invasive way. Ideally, they shunt a very small sample of the current to measure while dissipating minimal energy. Current sensors are frequently used to measure and control the load current in power supplies, safety circuits and a variety of control circuits. In applications where controlling the current is required, such as in power supplies, accurately sensing the magnitude of the current is a fundamental requirement. Coilcraft CPS manufactures current sensors and current sense transformers for measuring current up to 40 Amps at frequencies from 400 Hz to greater than 1 MHz.

Gate drive transformers are used to deliver the controlling gate-voltage pulses between the drain and source of a MOSFET, while providing isolation between the MOSFET and the controlling drive circuit. Gate-driver circuits need an isolated (floating) bias supply to maintain the required turn-on bias when the FET source rises to the input voltage. A gate drive transformer isolates the controlling gate-drive circuit from the switch node when driving the MOSFET gate and may also scale the output voltage via an appropriate primary‑to‑secondary turns ratio. Our off-the-shelf gate drive transformers simplify the design of your gate-drive circuit and shorten design cycle time. They utilize high-permeability ferrite cores to maximize magnetizing inductance and minimize magnetizing current.

For more information about transformer design, download the Coilcraft Structured Design Guide for Switching Transformers, for a step-by-step guide to transformer design or fill out the Power Transformer Design Worksheet.