NXP Brings Standard Packages to RF Power for Simplified Design and ManufacturingJune 06, 2018 by Paul Shepard
Ease of use and design re-use across frequencies have not traditionally been associated with RF power solutions — until now. Today, NXP Semiconductors N.V. has introduced two new power blocks that promise to become a new standard for years to come. The simplicity of these new devices lies in the availability of laterally diffused metal oxide semiconductor (LDMOS) technology for RF transistors in ubiquitous TO-247 and TO-220 power packages, that come with well-established assembly processes.
This is augmented with the simultaneous availability of very compact reference circuits that can be reused from 1.8 Megahertz (MHz) to 250 MHz. This results in considerable savings, fast time to market and optimized supply chain for most High Frequency (HF) and Very High Frequency (VHF) power systems.
NXP's new RF solutions include the MRF101AN 100W transistor that is housed in the TO-220 package, and the MRF300AN 300W transistor that is housed in the TO-247 package. While current plastic packages for high power RF require a precise solder reflow process, these transistors can be assembled to a printed circuit board (PCB) using a standard through-hole technology, reducing costs.
Heatsinking is also simplified since the transistors can be mounted vertically to a chassis, or in more creative and versatile ways such as under the PCB. This opens many options for the mechanical design, contributing to lower the Bill of Materials (BoM) and reduce time to market.
"RF Power is moving increasingly into new applications, where the requirements for ease of use, high performance and versatility are essential," said Pierre Piel, senior director and general manager for multi-market RF power at NXP. "We continue our mission to ease the use of RF Power by delivering solutions that minimize design requirements, reduce time to market and simplify the supply chain for our customers."
Flexibility Without Compromise on Performance
At 40.68 MHz, the MRF300AN outputs 330W Continuous Wave (CW), with 28dB of gain and 79 percent efficiency. As part of NXP's series of extremely rugged transistors, the family is designed for use in unforgiving industrial applications and can withstand 65:1 Voltage Standing Wave Ratio (VSWR).
This performance is supported by 2 x 3 inch (5.1 x 7.1 centimeters) power block reference designs that use cost-effective PCB material. With only a change of coils and discrete components, and no change to the PCB layout, the board can be adapted to support any other frequency from 1.8 to 250 MHz. This ensures quick design cycle for RF designers to develop power amplifiers that address new markets.
For even more flexibility, each transistor comes in two configurations. For example, the MRF101BN mirrors the pin-out of the MRF101AN, enabling a compact push-pull layout to address wideband applications without compromise on efficiency.
The MRF101AN and MRF300AN target Industrial, Scientific and Medical (ISM) applications as well as HF and VHF communications. A new market is also expected with switch-mode power supply, since this technology enables switching at higher frequencies than existing solutions, reducing the size of other components of the BoM. The devices are part of NXP's Product Longevity Program guaranteeing availability for 15 years.
The MRF300AN is available now. The MRF101AN is currently sampling, with production expected in September 2018. Reference circuits for the MRF300AN are available for 27MHz, 40.68MHz, 81.36MHz and 230MHz.