Overview
The AD9548BCPZ, produced by Analog Devices Inc., is a quad/octal input network clock generator and synchronizer. This component is designed to provide synchronization for various systems, including synchronous optical networks (SONET/SDH), wireless base station controllers, and cable infrastructure. The AD9548 generates an output clock synchronized to one of up to four differential or eight single-ended external input references, ensuring low jitter and phase noise through its digital PLL. It operates over an industrial temperature range of −40°C to +85°C and features a digitally controlled loop and holdover circuitry to maintain a clean output clock even when all references have failed.
Key Specifications
| Parameter | Min | Typ | Max | Unit | Test Conditions/Comments |
|---|---|---|---|---|---|
| Input Reference Frequencies | 1 Hz | 750 MHz | |||
| Output Frequencies | 450 MHz | ||||
| Input Reference Configurations | 4 pairs of reference input pins, each pair configurable as a single differential input or as 2 independent single-ended inputs | ||||
| Output Configurations | 4 pairs of clock output pins, each pair configurable as a single differential LVDS/LVPECL output or as 2 single-ended CMOS outputs | ||||
| Temperature Range | −40°C | +85°C | Industrial temperature range | ||
| Package | 88-lead LFCSP | ||||
| Power Dissipation | 13 mW | mW | Full power-down conditions, typical configuration |
Key Features
- Supports Stratum 2 stability in holdover mode
- Supports reference switchover with phase build-out and hitless reference switchover
- Auto/manual holdover and reference switchover
- Reference validation and frequency monitoring (1 ppm)
- Programmable input reference switchover priority
- 30-bit programmable input reference divider and 30-bit integer and 10-bit fractional programmable feedback divider
- Programmable digital loop filter covering loop bandwidths from 0.001 Hz to 100 kHz
- Optional low noise LC-VCO system clock multiplier and crystal resonator for system clock input
- On-chip EEPROM to store multiple power-up profiles
- Software controlled power-down
Applications
- Network synchronization
- Cleanup of reference clock jitter
- GPS 1 pulse per second synchronization
- SONET/SDH clocks up to OC-192, including FEC
- Stratum 2 holdover, jitter cleanup, and phase transient control
- Stratum 3E and Stratum 3 reference clocks
- Wireless base station controllers
- Cable infrastructure
- Data communications
Q & A
- What is the primary function of the AD9548BCPZ?
The AD9548BCPZ is a quad/octal input network clock generator and synchronizer, designed to generate an output clock synchronized to external input references.
- What are the input reference frequency ranges supported by the AD9548BCPZ?
The AD9548BCPZ supports input reference frequencies from 1 Hz to 750 MHz.
- What types of output configurations are available on the AD9548BCPZ?
The AD9548BCPZ offers output configurations including single differential LVDS/LVPECL outputs or as 2 single-ended CMOS outputs.
- What is the operating temperature range of the AD9548BCPZ?
The AD9548BCPZ operates over an industrial temperature range of −40°C to +85°C.
- What package type is the AD9548BCPZ available in?
The AD9548BCPZ is available in an 88-lead LFCSP package.
- Does the AD9548BCPZ support Stratum 2 stability in holdover mode?
Yes, the AD9548BCPZ supports Stratum 2 stability in holdover mode.
- What is the purpose of the on-chip EEPROM in the AD9548BCPZ?
The on-chip EEPROM is used to store multiple power-up profiles.
- Can the AD9548BCPZ perform reference switchover with phase build-out?
Yes, the AD9548BCPZ supports reference switchover with phase build-out and hitless reference switchover.
- What are some of the key applications of the AD9548BCPZ?
The AD9548BCPZ is used in network synchronization, cleanup of reference clock jitter, GPS 1 pulse per second synchronization, SONET/SDH clocks, and more.
- How does the AD9548BCPZ maintain a clean output clock when all references have failed?
The AD9548BCPZ maintains a clean output clock through its digitally controlled loop and holdover circuitry.
