RC38208/RC38108 FemtoClock®3 Attenuator and Clock Generator

Renesas RC38208 and RC38108 are ultra-low phase noise jitter attenuators, multi-frequency clock synthesizers, and digitally controlled oscillators (DCO). These flexible, low-power devices output clocks with ultra-low in-band phase noise and spurious for 4G and 5G RF transceivers and with jitter below 25 fs RMS for 112 Gbps and 224 Gbps SerDes.

The RC38208A evaluation board (Revision A, RC38208A-EVK) allows users to evaluate the board’s high-performance synthesizer and jitter attenuator applications. The kit comes with basic hardware and GUI setup using Renesas IC Toolbox (RICBox™) software, board power-up instructions, instructions to get active output signals using a provided configuration file, and hardware modifications required for different conditions.

Features

• Ultra-low phase noise synthesizer with jitter below 25 fs RMS, 12 kHz to 20 MHz with 4 MHz HPF
• Two independent low-phase noise sync domains
• Four independent low-phase noise frequency domains
• Support for JESD204B/C
• Time sync block with time to digital converter (TDC), time of day (TOD) counter, and PTP clocks
• 8 clock outputs with independent integer dividers
• 6: LVDS, HCSL (AC-LVPECL) or CML
• 2: LVDS, HCSL (AC-LVPECL) or LVCMOS
• Output frequency range
• CML: DC to 2.5 GHz
• LVDS or HCSL: DC to 1 GHz
• LVCMOS: DC to 250 MHz
• Two differential clock inputs configurable as four single-ended clock inputs
• Operates from a 1.8 V supply
• Clock inputs tolerate 1.8 V input when the device is powered off, sinking less than 1 mA
• CLKIN input frequency range: DC to 1 GHz
• Time sync TDC supports 1PPS and PP2S inputs
• DPLLs comply with ITU-T G.8262 and G.8262.1
• DPLL input-to-output phase variation ≤ 100ps
• DCO frequency resolution < 10 to 13
• Package: 7 mm × 7 mm, 64-BGA

Applications

• Timing for optical front-end DAC/ADC and DSP
• Reference clock for 112 Gbps and 224 Gbps SerDes
• 5G distribution units (DU), switches, and routers
• High-performance DCO for precision time protocol (PTP) based clocks