Renesas Electronics recently announced the expansion of its timing solutions portfolio with a new sub-100fs point-of-use clock solution for data center, server, and network infrastructure markets. The new FemtoClock2 family includes ultra-low jitter clock generators and jitter attenuators in a small 4x4 mm2 package, enabling cost-effective and simple clock tree implementation for next-generation, high-speed interconnect designs. 

Featuring best-in-class jitter as low as 64fs RMS, FemtoClock2 enables customers to easily meet next-generation PAM4 requirements on new switch or router designs. With a 4x4 mm2 form factor, the FemtoClock2 family is less than one third the size of similar solutions on the market. This allows designers to place the clock source at the point of use – very close to the device receiving the clock signal – for streamlined PCB layout design, reduced cross talk, and cleaner signals. Flexibility makes the family useful in many applications. FemtoClock2 can be configured as a DCO, clock generator, or jitter attenuator, offering valuable design flexibility and reuse.

“PAM4 technology is enabling a major leap in data transmission rates in both communications and data center segments resulting in stringent requirement on the clock in such systems,” said Bobby Matinpour, Vice President of Timing Products, Data Center Business Division at Renesas. “Expanding our popular FemtoClock lineup, Renesas offers a new high-performance family that delivers superior jitter performance with low power in a small form factor, enabling placement of the clock anywhere on the board at the point of use. This greatly simplifies the design by eliminating the additive jitter associated with the extensive clock routing on the board.”

Key Features of the FemtoClock2 Family

  • As low as 64fs (typ) RMS jitter 
  • Low power consumption of 600mW  
  • 4x4 mm2 in 24- and 28-pin QFN packages
  • Single & dual input options with four differential outputs 
  • Power supply noise rejection better than -80dB
  • Output-to-output isolation of -80dBc 
  • Compliant with ITU-T G.8262 and G.8262.1 for enhanced synchronous Ethernet/OTN
  • Integrated crystal option for more space savings

The RC32504A and RC22504A FemtoClock solutions and an evaluation board are available now. For more information, please visit