NB4N507A

NB4N507A 3.3V/5V, 50 MHz to 200 MHz PECL Clock Synthesizer Description 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 (see Figure 7). 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. The PECL outputs are 15 mA open collector and must be DC loaded and AC terminated. See Figures 4 and 6. Features ăInput Crystal Frequency of 10 - 27 MHz ăEnable Usage of Common Low-Cost Crystal ăDifferential PECL Output Clock Frequencies up to 200 MHz ăDuty Cycle of 48%/52% ăOperating Range: VCC = 3.0 V to 5.5 V ăIdeal for SONET Applications and Oscillator Manufacturers ăAvailable in Die Form ăPackaged in 16-Pin Narrow SOIC ăPb-Free Packages are Available* http://onsemi.com SOIC-16 D SUFFIX CASE 751B MARKING DIAGRAM NB4N507AG AWLYWW Osc PD CP VCO PECL CLKOUT CLKOUT Mult OE A = Assembly Location WL = Wafer Lot Y = Year WW = Work Week G = Pb-Free Package S0 S1 Figure 1. Simplified Logic...