Description The NB3H5150−01 is a high performance Multi−Rate Clock generator which simultaneously synthesizes up to four different frequencies from a single PLL using a 25 MHz input reference. The reference frequency can be provided by a crystal, LVCMOS/LVTTL, LVPECL, HCSL or LVDS differential signals. The REFMODE pin will select the reference source. Three output banks (CLK1A/CLK1B to CLK3A/CLK3B) produce user selectable frequencies of: 33.33 MHz, 50 MHz, 100 MHz, 125 MHz, or 156.25 MHz and have ultra−low noise/jitter performance of less than 0.3 ps. The fourth output bank (CLK4A/CLK4B) can produce the following integer and FRAC−N frequencies in pin−strap mode: 25 MHz, 33.33 MHz, 66.66 MHz, 100 MHz, 125 MHz, 133.33 MHz, 156.25 MHz or 161.1328 MHz. Each output block can create two single−ended in−phase LVCMOS outputs or one differential pair of LVPECL outputs. Each of the four output blocks is independently powered by a separate VDDO, 2.5 V/3.3 V for LVPECL, 1.8 V/2.5 V/3.3 V for LVCMOS. The serial (I2C and SMBUS) interface can be used to load register files into the NB3H5150−01 to program a variety of functions including the frequencies and output levels of each output which can be individually enabled and disabled.