Dual 156.25 MHz HCSL clock for PCIe reference
The DSC2044FI1-H0006T delivers two 156.25 MHz HCSL outputs from a MEMS resonator — a common reference clock frequency for PCI Express Gen 1/2/3 and 10 GbE SerDes. Both outputs run at the same frequency, so a single oscillator feeds two clock lanes without an external fanout buffer. HCSL (High-Speed Current Steering Logic) output levels are specified for differential clock distribution with 100-ohm termination, matching the PCIe clock topology directly.
The 2.25V to 3.6V supply range covers both 2.5V and 3.3V rails — no separate LDO needed when the board carries either voltage.
Package and enable/disable control
Housed in a 14-VFQFN with exposed pad (3.20 mm x 2.50 mm, 0.90 mm height), the package requires a thermal via array under the pad for heat sinking — the 60 mA typical supply current at 156.25 MHz dissipates about 200 mW, so the pad must be soldered to a ground plane to keep junction temperature within limits.