The ICS300 and ICS301 QTClocksTM generate a high quality, high frequency clock output and a reference from a low frequency crystal or clock input. They are designed to replace crystals and crystal oscillators in most electronic systems. The ICS302 can accept a higher frequency clock input to generate up to 200 MHz. The devices contain a One Time Programmable (OTP) ROM which is factory programmed with the PLL divider values to output a broad range of frequencies, from 6 to 200 MHz, allowing customer requests for different frequencies to be shipped in 1-3 days. Using Phase-Locked-Loop (PLL) techniques, the devices run from a standard fundamental mode, inexpensive crystal, or clock. They are smaller and less expensive than one oscillator.