The XC2173 series are high frequency, low power consumption CMOS ICs with built-in crystal oscillator, divider and clock multiplier PLL circuits. Output is selectable from any one of the following values for f0 : f0 x 5, f0 x 6, f0 x 7, f0 x 8, f0/2, f0/4, f0/8. With an oscillation capacitor & oscillation feedback resistor built-in, a stable oscillator circuit can be put together using only an external crystal oscillator. By connecting an external standard clock, the above mentioned output frequencies can be achieved.