XOs And VCXOs With Any-Rate Frequency Synthesis

Hardware designers have traditionally used multiple fixed-frequency XOs, VCXOs or voltage-controlled SAW oscillators (VCSO) in designs requiring a system timing architecture that is reconfigurable to operate at different frequencies. This approach is expensive, requires complex analog phase locked loop (PLL) design and layout and slows time-to-market for new hardware designs.

The Si570/1 programmable XOs and VCXOs replace multiple fixed-frequency oscillators with a single, frequency-flexible oscillator that can generate any frequency from 10 MHz to 1.4 GHz, significantly reducing component count, system cost and board space while simplifying PLL design and layout. The Si570/1 offer improved system reliability because multiple fixed-frequency oscillators, each representing a potential point of failure, are eliminated.

The Si570/1 operating frequency is user-programmable via an industry-standard I2C interface, simplifying device programming and easing reconfigurability. The Si570/1 can be reprogrammed an unlimited number of times, enabling system designers to reuse a common timing architecture across a wide range of end applications, simplifying design and speeding time-to-market.

“We’ve applied our proven DSPLL technology to dramatically simplify timing architectures in applications requiring multiple clock frequencies. The Si570 XO and Si571 VCXO address the growing need for low jitter, frequency-flexible clock sources, enabling hardware designers to decrease the number of oscillators in their designs while reducing cost and design time,” said David Bresemann, vice president of Silicon Laboratories. “With the addition of the Si570/1 family of any-rate oscillators, Silicon Labs has created the industry’s broadest portfolio of reconfigurable, frequency-agile precision clock and frequency control products.”

The Si570/1 devices are available in an industry standard, RoHS-compliant 5 x 7 mm surface mount package with support for all common output formats (LVPECL, LVDS, CMOS and CML). The family offers three speed grades: 10 MHz to 1.4 GHz, 10 MHz to 810 MHz and 10 MHz to 215 MHz. The Si570 Any-Rate XO is available with two temperature stability options, +/-20 ppm and +/-50 ppm. The Si571 Any-Rate VCXO has a wide selection of absolute pull range (APR) options ranging from +/-12 ppm to +/-375 ppm, giving hardware designers increased flexibility when choosing the best device for an application. The Si570/1 support operation from -40 to +85 C.