Ultra-low-power PLLs go wireless

Edited by the Electronicstalk editorial team May 24, 2001

National Semiconductor has announced the LMX23xxU series of ultra-low-power dual-PLL frequency synthesisers, the latest addition to its family of PLLatinum PLLs for wireless applications.

National Semiconductor has announced the LMX23xxU series of ultra-low-power dual phase locked loop (PLL) frequency synthesisers, the latest addition to its family of PLLatinum PLLs for wireless applications.

This new family is pin- and software-compatible with the current LMX23xxL family of PLLs, providing easy upgrade, and consumes up to 43% less power.

Lower power consumption creates a higher level of performance for cell phones - including longer handset talk and standby time, as well as longer battery life, and lower handset weight and size.

"With the LMX23xxU family of PLLatinum PLLs, designers of portable wireless communications devices such as wireless handsets and cellular telephone systems can minimise current consumption and still enjoy the best-in-class RF performance that all our PLLatinum PLLs provide", said Armin Konrad, who is doing technical marketing for National's RF Building Blocks.

"By using 43% less power than the previous generation of PLLs, these new products provide the lowest power consumption available in the industry.

In addition to providing numerous engineering and design benefits, lower power consumption creates a much more enjoyable experience for the ultimate consumer of wireless communications devices - including additional talk time, longer battery life and smaller-sized handsets".

The LMX23xxU family of six dual PLLs offers all the features of National's PLLatinum product line, including ultra low current consumption, low phase noise and Fastlock mode, plus a 3 to 6dB improvement in spurial performance.

Using a digital phase locked loop technique combined with a high quality reference oscillator and voltage controlled oscillator, the LMX23xxU family generates very stable, low noise local oscillator signals for up and down conversion in wireless communication devices.

LMX2330U, LMX2331U, LMX2332U, LMX2336U and LMX2377U products are designed to be used as local oscillators for RF and first IF of a dual conversion transceiver.

LMX2377U offers the additional feature of a 1.8V data interface, making it compatible with low voltage processor I/O and control logic.

LMX2335U is designed for applications requiring two independent transmit and receive PLLs.

The entire LMX23xxU family except for the LMX2335U is available in CSP24 and TSSOP20 packages.

The LMX2335U is available in CSP16 and TSSOP16 packages.