April 2, 2003 - National Semiconductor Corporation (NYSE:NSM) today expanded its wireless product offerings with the introduction of a new family of PLLatinum™ phase lock loops (PLLs) for cellular applications. This new family of delta-sigma fractional-N PLLs uses digital modulation techniques for superior phase noise, spurs and lock time performance in applications requiring exceptionally fine frequency resolution. With these products, National raises the bar for performance with the lowest power consumption delta-sigma PLLs in the industry. The first member of this new family is the LMX2470, housed in a 3.5mm by 4.5mm by 0.6mm ultra-thin chip-scale package ideal for use in 2, 2.5G and 3G mobile handsets, base stations, WLANs and other wireless communication systems. The LMX2470 is available now. Additional members of the product family will be introduced throughout the year.
“National’s new LMX247x family of delta-sigma PLLs offers our customers a higher level of performance not found in other PLL products. The sizable improvement in phase noise, spurs, lock time and power consumption that the new family offers translates into improved radio sensitivity for fewer dropped calls, improved voice and data quality, longer battery life and improved system performance,” said Paul Boyer, product marketing manager for National’s Wireless Group. “Building upon National’s leadership in the PLL market, the LMX247x family will allow manufacturers of mobile handsets to meet their designs’ increasingly stringent performance and power requirements.”
About the LMX2470
The LMX2470 is the first product offering from National’s new family of high performance delta-sigma PLLs. It features a maximum RF operating frequency of 2.6 GHz and an 800 MHz IF frequency. The LMX2470 is the industry’s first delta-sigma PLL that allows users to software select the modulator order. It is also the industry’s only delta-sigma PLL that has true cycle slip reduction and integrated timeout counters for fastlock to minimize software overhead. The product is highly flexible, with 32 current (charge pump) levels and 4 levels of comparison frequency reduction. It is optimized for very low power consumption, with 4.1 mA total current at a 2.5 volt supply voltage.
The LMX2470 has up to a 22-bit selectable modulus that enables very high comparison frequencies for excellent normalized phase noise performance of –210 dBc/Hz for high system sensitivity. The on-board crystal doubler can be used to double the crystal frequency to allow larger comparison frequencies, resulting in –213 dBc/Hz normalized phase noise. With low fractional spurs of <-90 dBc, the LMX2470 has the lowest fractional spurs in the industry to minimize cross channel modulation for greater voice and data accuracy.
The LMX2470’s delta-sigma modulation pushes in-band noise and spurs to outside the loop bandwidth. The higher the modulator order, the more noise and spurs can be pushed to higher frequencies and filtered out by the loop filter. The LMX2470 is the only delta-sigma PLL in the industry that gives the user the ability to program the modulator up to modulator order 4. This ability gives the designer the utmost flexibility to optimize the local oscillator’s phase noise, spurs and lock time.
Pricing and Availability
The LMX2470 is available now for $2.07 in 1k quantities. More information about the product is available at http://www.national.com/pf/LM/LMX2470.html. A high resolution, downloadable photo is available at http://www.national.com/company/pressroom/gallery/wireless.html.
About National Semiconductor
National Semiconductor is the premier analog company driving the information age. Combining real-world analog and state-of-the-art digital technology, the company is focused on analog-based semiconductor products, which include stand-alone devices and subsystems in the areas of power management, imaging, display drivers, audio, amplifiers and data conversion. The company targets key markets such as wireless, displays, information infrastructure and a broad range of portable applications. With headquarters in Santa Clara, California, National reported sales of $1.5 billion for its most recent fiscal year. Additional company and product information is available on the World Wide Web at www.national.com.
