78P2351-IGTR/F Maxim Integrated Products, 78P2351-IGTR/F Datasheet - Page 9

• Manufacturer Part Number: 78P2351-IGTR/F
• Description: LINE INTERFACE UNIT 100-LQFP
• Manufacturer: Maxim Integrated Products

Specifications of 78P2351-IGTR/F

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Design Guidelines for TERIDIAN 78P235x LIUs
COAXIAL CONNECTORS
Coaxial connectors must be of the 75-ohm variant to avoid compromising the mechanical properties of the mating
receptacle and to match the impedance of the line. For optimal EMC performance and ESD immunity at the
faceplate, it is critical that the shield of the coax connectors be well bonded to the frame or chassis in any board
design. The system enclosure should also be properly grounded at the earth facility.
For optimal space savings, Teridian suggests the use of 75 ohm DIN 1.0/2.3 connectors (BT Type 54), which can
be sourced from the following suppliers.
CRYSTAL OSCILLATOR REQUIREMENTS
The following requirements are provided with the assumption that plesiochronous transmit timing mode is
enabled. If using a crystal oscillator in any of the synchronous modes, the clock stability over the life of the
oscillator will be inherently limited by the SONET/SDH/PDH bit rate requirements of +/- 20ppm for STS-3/STM-1
and +/-15ppm for E4.
Several factors to consider when selecting a crystal oscillator for plesiochronous mode:
Evaluation of the following crystal oscillators at Teridian showed no appreciable differences in jitter performance.
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Xian Connector
Compel
Radiall
SIAM
Amphenol
Tekmos
Tru
AMP / Tyco
Hsu-Tsan Group





Frequency tolerance / stability (70ppm or better)
Aging (not to exceed 100ppm over life)
Rise / Fall time
Output amplitude (must be at least 2V signal swing)
Period jitter (up to 220ps evaluated without any appreciable effects)
Vendor
CTS
Ecliptek
SaRonix
Abracon
Crystek
 2008 Teridian Semiconductor Corp.
Part number
CB3LV-3C-19.440000
EH2645ETTS-19.440M
S1613B-19.44
ASV-19.44MHz-C
C3392-19.44MHz
Rev 2.1