The AD809 is a 155.52 MHz frequency synthesizer that can be used to generate a 155.52 MHz bit clock for SONET/SDH/Fiber in the Loop systems. The device has a low cost, on-chip VCO that locks to either 8× or 16× the frequency at the 19.44 MHz or 9.72 MHz input. No external components are needed for frequency synthesis; however, the user can adjust the input frequency to achieve optimum performance.
The AD809 provides a 155.52 MHz ECL/PECL output clock derived from a 19.44 MHz or 9.72 MHz reference. It features low output jitter (2.0 Degrees RMS), low power consumption (90 mW) and operates from a single +5 V or –5.2 V supply. The device includes an on‑chip VCO, input multiplexing for loop‑timed applications, and supports both x8 and x16 synthesis ratios.
The datasheet details electrical specifications, pin descriptions, recommended PCB layout, grounding, and termination practices. An evaluation board schematic and mechanical dimensions for the 16‑pin narrow‑body SOIC package are also provided.
| Frequency Synthesis Range | 155.52 MHz |
|---|---|
| Input Frequency Options | 19.44 MHz or 9.72 MHz |
| Output Jitter | 2.0 Degrees RMS |
| Power Consumption | 90 mW |
| Supply Voltage | +5 V or -5.2 V |
| Package | 16‑Pin Narrow Body SOIC |
The AD809 accepts a 19.44 MHz or 9.72 MHz reference input.
The output jitter is specified as 2.0 Degrees RMS.
It operates from a single supply of +5 V or –5.2 V.
The device is available in a 16‑Pin Narrow Body SOIC package.