3.3, 2.5 and 1.8-V Clock Generator Family

10th July 2007

ES Admin

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Texas Instruments has introduced a family of highly-programmable, one to four phase-lock loop (PLL) clock generator devices with the ability to generate up to nine output clock sources from a single input frequency. Each output can be programmed in-system for any clock frequency up to 230 MHz. These features provide a number of system benefits such as reduced power consumption, shorter lead time and the flexibility to easily upgrade the clock without redesigning the system. These benefits ultimately reduce cost for a broad range of consumer applications such as IP set-top boxes or phones, digital media systems such as digital televisions, streaming media and printers, navigation systems and portable devices.

The new CDCE9xx and CDCEL9xx family of clock generators ranges from one to four PLLs with very low jitter at 60 picoseconds typical. The CDCE9xx devices provide either 2.5-V or 3.3-V outputs, and the CDCEL9xx provide 1.8-V outputs, enabling the low-power capability needed for portable devices. Each PLL supports spread-spectrum clocking (SSC) to reduce electro-magnetic interference (EMI) to enable compliance with EMC regulations.

The family provides a variety of programmability options including the ability to program and customize the devices in-system through I2C and EEPROM. By offering footprint compatibility across the family, designers can adapt the system design easily without changing hardware, which reduces cost and enables the designer to simply increase or decrease the number of clock outputs. The new family of devices further simplifies system design by replacing a number of components in the system
including crystals, oscillators, buffers and PLLs.

The new clock devices are optimized to work with TI's DaVinciT-based processors by generating any audio, video, processor or interface clock to drive the digital processor, audio digital-to-analog converter or codec and Ethernet or USB controller. The on-chip voltage-controlled crystal oscillator (VCXO) allows frequency synchronization of different data streams.

The CDCE949 is available now in 24-pin TSSOP package. The remaining devices in the family will be available throughout 2007 in 20-pin, 16-pin and 14-pin TSSOP packages. In addition, evaluation modules (EVMs) to evaluate the performance of the family are available.