The NB4N507A is a precision clock synthesizer which generates a very low jitter differential PECL output clock. It produces a clock output based on an integer multiple of an input reference frequency. The NB4N507A accepts a standard fundamental mode crystal, using Phase-Locked-Loop (PLL) techniques, will produce output clocks up to 200 MHz. In addition, the PLL circuitry will produce a 50% duty cycle square-wave clock output. The NB4N507A can be programmed to generate a selection of input reference frequency multiples. An exact 155.52 MHz output clock can be generated from a 19.44 MHz crystal and the x8 multiplier selection. The NB4N507A is intended for low output jitter clock generation.