841N4830 Datasheet | Renesas

Femto Clock® NG Crystal-to-HCSL Frequency Synthesizer General Description The 841N4830 is a 3 HCSL, 1 LVPECL and 2 LVCMOS output Synthesizer optimized to generate PCI Express reference clock frequencies. The device uses IDT’s fourth generation Femto Clock® NG technology for synthesis of high clock frequency at very low phase noise. It provides low power consumption with good power supply noise rejection. Using a 25MHz, 12p F parallel resonant crystal, the following frequencies can be generated: 100MHz, 50MHz and 25MHz. Maximum rms phase jitter of 0.36ps, easily meets PCI Express jitter requirements. The 841N4830 is packaged in a small 32-pin VFQFN package. Features - Fourth generation Femto Clock® Next Generation (NG) technology - Three differential HCSL outputs, one differential LVPECL and two single-ended LVCMOS/LVTTL outputs - Crystal oscillator interface designed for a 25MHz, 12p F parallel resonant crystal - CLK/n CLK input pair can accept the following differential input levels: LVPECL, LVDS, HCSL - A 25MHz crystal generates output frequencies of: 100MHz, 50MHz and 25MHz - VCO frequency: 2GHz - RMS Phase Jitter @ 100MHz, (12k Hz - 20MHz) using a 25MHz crystal: 0.36ps (maximum) - Power supply noise rejection PSNR: -45d B (typical) - PCI Express Gen 2 (5 Gb/s) jitter pliant - Full 3.3V supply mode - -40°C to 85°C ambient operating temperature - Available in lead-free (Ro HS 6) package Block Diagram n OE_REF Pulldown PLL_BYPASS Pulldown n OEA Pulldown XTAL_IN XTAL_OUT CLK Pulldown n CLK Pullup CLK_SEL Pullup 25MHz 0 1 IREF DIV2_QB Pullup n OEB Pulldown PFD & Femto Clock® NG VCO 2GHz ÷20 0 ÷1 0 ÷80 ÷2...