The MK3720 is a low cost, low jitter, high performance 3.3 Volt VCXO and PLL clock synthesizer designed to replace expensive 13.5, 27, or 54MHz VCXOs. The patented on-chip Voltage Controlled Crystal Oscillator accepts a 0 to 3.3 V input voltage to cause the output clocks to vary by 100 ppm. Using our patented VCXO and analog/digital Phase-Locked Loop (PLL) techniques, the device uses an inexpensive external 13.5 MHz pullable crystal input to produce output clocks of 13.5 MHz, 27 MHz, and 54 MHz .