DS3105_09 Datasheet, PDF (1/120 Pages) Maxim Integrated Products – Line Card Timing IC

19-4628; Rev 3; 5/09
General Description
The DS3105 is a low-cost, feature-rich timing IC for
telecom line cards. Typically, the device accepts two
reference clocks from dual redundant system timing
cards. The DS3105 continually monitors both inputs
and performs automatic hitless reference switching if
the primary reference fails. The highly programmable
DS3105 supports numerous input and output
frequencies including frequencies required for
SONET/SDH, Synchronous Ethernet (1G, 10G, and
100Mbps), wireless base stations, and CMTS
systems. PLL bandwidths from 18Hz to 400Hz are
supported, and a wide variety of PLL characteristics
and device features can be configured to meet the
needs of many different applications.
The DS3105 register set is backward compatible with
Semtech’s ACS8525 line card timing IC. The DS3105
pinout is similar but not identical to the ACS8525.
Applications
SONET/SDH, Synchronous Ethernet, PDH, and
Other Line Cards in WAN Equipment Including
MSPPs, Ethernet Switches, Routers, DSLAMs,
and Wireless Base Stations
Ordering Information
PART
DS3105LN
DS3105LN+
TEMP RANGE
-40C to +85C
-40C to +85C
PIN-PACKAGE
64 LQFP
64 LQFP
+Denotes a lead(Pb)-free/RoHS-compliant package.
SPI is a trademark of Motorola, Inc.
DS3105
Line Card Timing IC
Features
 Advanced DPLL Technology
 Programmable PLL Bandwidth: 18Hz to 400Hz
 Hitless Reference Switching, Automatic or Manual
 Holdover on Loss of All Input References
 Frequency Conversion Among SONET/SDH,
PDH, Ethernet, Wireless, and CMTS Rates
 Five Input Clocks
 Two CMOS/TTL Inputs (≤ 125MHz)
 Two LVDS/LVPECL/CMOS/TTL (≤ 156.25MHz)
 Backup Input (CMOS/TLL) in Case of Complete
Loss of System Timing References
 Three Optional Frame-Sync Inputs (CMOS/TTL)
 Continuous Input Clock Quality Monitoring
 Numerous Input Clock Frequencies Supported
Ethernet xMII: 2.5, 25, 125, 156.25MHz
SONET/SDH: 6.48, N x 19.44, N x 51.84MHz
PDH: N x DS1, N x E1, N x DS2, DS3, E3
Frame Sync: 2kHz, 4kHz, 8kHz
Custom Clock Rates: Any Multiple of 2kHz Up to
131.072MHz, Any Multiple of 8kHz Up to
155.52MHz
 Two Output Clocks
 One CMOS/TTL Output (≤ 125MHz)
 One LVDS/LVPECL Output (≤ 312.50MHz)
 Two Optional Frame-Sync Outputs: 2kHz, 8kHz
 Numerous Output Clock Frequencies Supported
Ethernet xMII: 2.5, 25, 125, 156.25, 312.5MHz
SONET/SDH: 6.48, N x 19.44, N x 51.84MHz
PDH: N x DS1, N x E1, N x DS2, DS3, E3
Other: 10, 10.24, 13, 30.72MHz
Frame Sync: 2kHz, 8kHz
Custom Clock Rates: Any Multiple of 2kHz Up to
77.76MHz, Any Multiple of 8kHz Up to
311.04MHz, Any Multiple of 10kHz Up to
388.79MHz
 General
 Suitable Line Card IC for Stratum 3/3E/4, SMC,
SEC
 Internal Compensation for Master Clock Oscillator
 SPI™ Processor Interface
 1.8V Operation with 3.3V I/O (5V Tolerant)
 Industrial Operating Temperature Range
Maxim Integrated Products 1
Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of
any device may be simultaneously available through various sales channels. For information about device errata, go to:
www.maxim-ic.com/errata. For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or
visit Maxim’s website at www.maxim-ic.com.