AD9520-4 is a 12 LVPECL/24 CMOS output clock generator with integrated 1.6 GHz VCO, features low phase noise, phase-locked loop (PLL), 1 differential or 2 single-ended reference inputs, 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, selectable revertive/nonrevertive switching, glitch-free switchover, automatic recover from holdover, digital or analog lock detect, optional zero delay operation.
The AD9520-4 is a 12‑output clock generator that provides LVPECL and CMOS outputs with sub‑picosecond jitter performance. It includes an on‑chip PLL and VCO that can be tuned from 1.4 GHz to 1.8 GHz, and it also supports an external VCO/VCXO up to 2.4 GHz. The device offers flexible reference inputs, automatic reference switchover, zero‑delay operation, and a serial SPI/I²C control port.
The datasheet lists detailed electrical specifications, power‑supply requirements, PLL characteristics, clock‑input and output parameters, and timing characteristics. It also provides application notes for high‑speed data‑center, wireless, and instrumentation uses, along with design guidelines for PCB layout and termination.
| VCO frequency range (internal) | 1.4 GHz – 1.8 GHz |
|---|---|
| Maximum LVPECL output frequency | 2.4 GHz |
| Operating temperature range | ‑40 °C to +85 °C |
| Supply voltage (VS) | 3.135 V – 3.465 V (typical 3.3 V) |
| Phase noise @ 1 kHz offset | ‑58 dBc/Hz |
The on‑chip VCO can be tuned from 1.4 GHz to 1.8 GHz, and an external VCO/VCXO up to 2.4 GHz may also be used.
The AD9520‑4 provides twelve LVPECL outputs arranged in four groups.
The core supply (VS) nominally runs at 3.3 V, with a range of 3.135 V to 3.465 V.
The LVPECL outputs can reach up to 2.4 GHz.