I2C Programmable Ethernet Clock Generator
The 8T49N4811 is a highly flexible FemtoClock® NG pin-programmable clock generator suitable for networking and communications applications. It is able to generate five different output frequencies with multiple copies of each. A fundamental mode crystal, single-ended, or differential input reference may be used as the source for the output frequency.
The use of pin-programming to select the input source / frequency, desired output frequencies and output styles allow a single device to be used in a wide variety of applications without the need for register programming.
Selection pins use 3-level options to maximize flexibility while minimizing package size. Selection is performed by tying a selection pin high or low or by leaving it floating, eliminating the need for passive components to drive a desired logic level.
- Fourth generation FemtoClock® NG technology
- Generates multiple copies of 25MHz, 50MHz, 100MHz, 125MHz, 156.25MHz or 312.5MHz
- Typical input frequency is 25MHz, with optional 125MHz and 156.25MHz input support
- Differential outputs are pin programmable for LVDS or LVPECL
- RMS phase jitter at 156.25MHz: <300fs typical
- Power Supply Rejection Ratio better than -50dBc from 10k-1.5MHz at 3.3V power supply
- Full 3.3V and 2.5V Supply Voltages
- -40°C to +85°C ambient operating temperature
- 56-pin VFQFPN, lead-free (RoHS 6) packaging