●GENERAL DESCRIPTION
●The AD9520-21 provides a multioutput clock distribution function with subpicosecond jitter performance, along with an on-chip PLL and VCO. The on-chip VCO tunes from 2.02 GHz to 2.335 GHz. An external 3.3 V/5 V VCO/VCXO of up to 2.4 GHz can also be used.
●The AD9520 serial interface supports both SPI and I2C® ports. An in-package EEPROM can be programmed through the serial interface and store user-defined register settings for power-up and chip reset.
●The AD9520 features 12 LVPECL outputs in four groups. Any of the 1.6 GHz LVPECL outputs can be reconfigured as two 250 MHz CMOS outputs.
● FEATURES
● Low phase noise, phase-locked loop (PLL)
● On-chip VCO tunes from 2.02 GHz to 2.335 GHz
● Supports external 3.3 V/5 V VCO/VCXO to 2.4 GHz
● 1 differential or 2 single-ended reference inputs
● Accepts CMOS, LVDS, or LVPECL references to 250 MHz
● Accepts 16.67 MHz to 33.3 MHz crystal for reference input
● Optional reference clock doubler
● Reference monitoring capability
● Auto and manual reference switchover/holdover modes, with selectable revertive/nonrevertive switching
● Glitch-free switchover between references
● Automatic recovery from holdover
● Digital or analog lock detect, selectable
● Optional zero delay operation
● Twelve 1.6 GHz LVPECL outputs divided into 4 groups
● Each group of 3 has a 1-to-32 divider with phase delay
● Additive output jitter as low as 225 fs rms
● Channel-to-channel skew grouped outputs <16 ps
● Each LVPECL output can be configured as 2 CMOS outputs (for fOUT ≤ 250 MHz)
● Automatic synchronization of all outputs on power-up
● Manual synchronization of outputs as needed
● SPI- and I²C-compatible serial control port
● 64-lead LFCSP
● Nonvolatile EEPROM stores configuration settings
●APPLICATIONS
● Low jitter, low phase noise clock distribution
● Clock generation and translation for SONET, 10Ge, 10G FC, and other 10 Gbps protocols
● Forward error correction (G.710)
● Clocking high speed ADCs, DACs, DDSs, DDCs, DUCs, MxFEs
● High performance wireless transceivers
● ATE and high performance instrumentation
● Broadband infrastructures
