The PFD1K is a high frequency phase frequency detector with fully differential inputs and outputs. It features dual 7-bit programmable high speed prescalers which allow the PFD1K to operate up to 40 GHz for the reference and voltage controlled oscillator input frequency. The 8 GHz phase-frequency detector allows operation at higher reference frequencies with concurrent lower phase noise and PLL figure of merit. The PFD1K operates with a single positive or negative 3.3V supply, and is packaged in a 40-pin, 6mm x 6mm ceramic leadless surface mount package.