Power Transistors

Demand for smaller, higher efficiency power conversion products is driving adoption of transistor devices. The recent focus for these devices is on efficiency with an emphasis on higher voltages in smaller sizes. As size gets smaller, challenges of managing heat, space and reliability increase. That’s where Advanced Electronics Solutions from Rogers can make a big difference.

Power Transistors Must be Robust & Reliable

Today’s power transistors provide a wide variety of power management applications but, due to the nature of their purpose, all pose their own challenges. Thermal management, power distribution efficiency and reliability are critical. Power transistors come in many varieties, including:

• Insulated gate bipolar transistors (IGBTs) - Insulated gate bipolar transistors (IGBTs) combine an easily driven MOS gate with low conduction loss. They are the device of choice for high current and high voltage applications. IGBT manufacturers must balance tradeoffs between switching speed, conduction loss and ruggedness so the devices provide higher frequency and higher efficiency. IGBTs also have high input impedance, making them popular in DC and AC motor drives, UPS systems, power supplies and renewable energy (PV and wind). Their lower gate drive requirements and lower switching losses make them more efficient at smaller sizes and lower costs.
• Metal Oxide Semiconductor Field Effect Transistor (MOSFETs) - Power MOSFETs are extremely fast; the high switching speed causes low switching loss. They require very little gate drive power because of the insulated gate. In these respects, power MOSFETs approach the characteristics of an ideal switch. They can be found in most power supplies, DC-DC converters and low voltage motor controllers. Super junction MOSFETs are increasingly being used to increase the efficiency and reduce the size of power supplies.
• Bipolar junction transistors (BJTs) - Bipolar junction transistors (BJTs) offer very fast switching speed, very low conduction losses and high temperature operation in a robust package. Silicon Carbide BJTs feature very high current density levels, high gain and excellent switching performance. For low-power AC/DC power supplies, BJT-based solutions offer low cost and easy EMI design.

Solving Power Transistor Reliability & Efficiency Challenges

Ceramic substrates and busbars play a major role in power transistors by boosting performance, minimizing power losses and optimizing thermal management. Rogers’ ROLINX® busbars distribute power by acting as a custom liaison between the power source and the power transistor module, whether it be IGBTs, BJTs, MOSFETS or complete modules. Additionally, Rogers’ curamik® ceramic substrates cool components and provided interconnections at the semiconductor level.