A low noise 9.95/10.66 GHz PLO for optical applications

A 9.95/10.66 GHz monolithic low noise phase-locked oscillator (PLO) implemented in an InGaP HBT technology is presented. It consists of a voltage-controlled oscillator (VCO), a digital phase frequency detector (PFD) and digital frequency dividers. The reference frequency input can be in two ranges, 155 to 167 MHz (divided by 32 selected) or 620 to 668 MHz (divided by 8 selected). Two auxiliary outputs at 4.975/5.33 and 2.4875/2.665 GHz are provided. A PLO phase noise of -122 dBc/Hz is achieved at 10 kHz offset. The phase jitter is 20.3 fs rms in 10 kHz to 10 MHz. The MMIC dissipates 1.5 W with two power supplies, +3 V for the VCO and +5 V for the rest of the circuitry.