National Semiconductor family of clock jitter cleaners are capable of providing ultra low-noise clocks without external high-performance voltage-controlled crystal oscillator (VCXO) modules.

Using a simple external crystal and cascaded PLLatinum architecture, National’s clock jitter cleaners provide sub-200 femtosecond (fs) root-mean-square (RMS) jitter to improve system performance and accuracy. This level of performance rivals expensive VCXO modules.

The LMK04000 family consists of five precision clock conditioners: LMK04000B, LMK04001B, LMK04011B, LMK04031B and LMK04033B. These devices feature power-to-noise specifications that place them among National’s PowerWise family of energy-efficient products.

The LMK04000B and LMK04001B offer 24.4 mW-ps per channel, while the LMK04031B and LMK04033B are rated at 25.4 mW-ps per channel and the LMK04011B is 37.4 mW-ps per channel.

The LMK04000 devices provide clean clocks to analog-to-digital converters (ADC), digital-to-analog converters (DAC) and other high-performance components used in wireless infrastructure, test and measurement, and medical ultrasound and imaging equipment.

Wireless base station applications include single-carrier and multi-carrier GSM (GSM), Long Term Evolution (LTE), Universal Mobile Telecommunications System (UMTS), Worldwide interoperability for Microwave Access (WiMAX) and Code Division Multiple Access (CDMA) networks.

Pricing and availability

The LMK04011B, LMK04031B and LMK04033B are available now and the LMK04000B, LMK04001B are sampling now with production volumes expected in the first quarter of 2009. All devices are priced at $14.50 each in 1,000-unit quantities.

More information on these precision clock conditioners, or to order samples and an evaluation board, visit www.national.com/pf/LM/LMK04000B.html, www.national.com/pf/LM/LMK04001B.html, www.national.com/pf/LM/LMK04011B.html, www.national.com/pf/LM/LMK04031B.html and www.national.com/pf/LM/LMK04033B.html.

National’s clock design tool simplifies design, analysis and parts selection for a wide variety of applications. Visit www.national.com/timing.