T7256 Agere Systems, T7256 Datasheet - Page 30

• Manufacturer Part Number: T7256
• Description: (T7234 - T7256) Compliance
• Manufacturer: Agere Systems

T7234 Single-Chip NT1 (SCNT1) Euro-LITE Transceiver
Electrical Characteristics
S/T-Interface Receiver Common-Mode Rejection
Table 9. S/T-Interface Receiver Common-Mode Rejection
Crystal Characteristics
Table 10. Fundamental Mode Crystal Characteristics
These are the characteristics of a parallel resonant crystal for meeting the 100 ppm requirements of T1.601 for NT
operation. The parasitic capacitance of the PC board to which the T7234 crystal is mounted must be kept within the
range of 0.6 pF
Table 11. Internal PLL Characteristics
* Set by digital PLL; therefore, variations track U-interface line rate.
26
Common-mode Rejection (at device pins)
Center Frequency
Tolerance Including Calibration,
Drive Level
Series Resistance
Shunt Capacitance
Motional Capacitance
Total Pull Range
Jitter Transfer Function
Jitter Peaking
Temperature Stability, and Aging
Parameter
Parameter
Parameter
0.4 pF.
–3 dB point (NT), 18 kft 26 AWG
(continued)
Test Conditions
Symbol
1.5 Hz typical
TOL
C
DL
R
C
F
O
O
M
S
—
Symbol
CMR
With 25.0 pF of loading
Test Conditions
Maximum
Maximum
—
—
—
Specifications
Min
250
—
—
400
Specifications
Typ
1.0*
—
5*
3.0
12
15.36
Lucent Technologies Inc.
0.5
20
70
20%
20%
Max
February 1998
—
—
—
Data Sheet
Unit
mV
MHz
Unit
ppm
mW
pF
Unit
ppm
fF
Hz
dB