The LMK04806BISQ/NOPB is a PLLatinum jitter cleaner from Texas Instruments, built to reduce phase noise on a reference clock and distribute a clean signal across 14 outputs. Its 1.536 GHz maximum frequency sets the ceiling for the VCO and the output dividers — above that, the PLL loses lock and the jitter spec no longer holds. For a system clocking a 1 GSPS ADC or a 28 Gbps serializer, this part cleans the reference before the converter's own PLL multiplies it up. The 2:14 input-to-output ratio means one reference clock fans out to 14 devices — a typical use is distributing a clean 122.88 MHz or 245.76 MHz reference across multiple data converters on a mixed-signal board. Each output can be independently configured as LVCMOS, LVDS, or LVPECL, so the same part drives the ADC clock input (LVDS), the FPGA reference (LVCMOS), and the backplane (LVPECL) without external translators.
Package and board-fit — 64-WQFN with exposed pad
The datasheet recommends a 5×5 array of thermal vias under the pad — skipping them raises the junction temperature by about 15°C at the 3.45 V supply rail, pushing the PLL's in-band phase noise up by 2-3 dB. The exposed pad helps pull heat out at high ambient; without the pad soldered, the part derates above 70°C ambient.