pef2256e Infineon Technologies Corporation, pef2256e Datasheet - Page 98

• Manufacturer Part Number: pef2256e
• Description: E1/t1/j1 Framer And Line Interface Component For Long- And Short-haul Applications
• Manufacturer: Infineon Technologies Corporation

4.4.2
The analog transmitter transforms the unipolar bit stream to ternary (alternate bipolar)
return to zero signals of the appropriate programmable shape. The unipolar data is
provided by the digital transmitter.
Figure 26
Table 22
Parameter
t2 : t1
1)
Similar to the receive line interface three different data types are supported:
•
•
•
User’s Manual
Hardware Description
1
This value refers to an ideal transformer without any parasitics. Any transformer resistance or other parasitic
resistances have to be taken into account when calculating the final value of the output serial resistors.
(± 1%) [Ω]
Ternary Signal
Single-rail data is converted into a ternary signal which is output on pins XL1 and
XL2. The HDB3 and AMI line code is employed. Selected by FMR0.XC1/0 and
LIM1.DRS = 0.
Dual-rail data PCM(+), PCM(–) at multifunction ports XDOP/XDON with 50% or
100% duty cycle and with programmable polarity. Line coding is done in the same
way as in ternary interface mode. Selected by FMR0.XC1/0 and LIM1.DRS = 1.
Unipolar data on port XOID is transmitted either in NRZ (Non Return to Zero) with
100% duty cycle or in CMI (Code Mark Inversion or known as 1T2B) Code with or
without (FMR3.CMI) preprocessed HDB3 coding to a fiber-optical interface. Clocking
off data is done with the rising edge of the transmit clock XCLK (2048 kHz) and with
a programmable polarity. Selection is done by FMR0.XC1 = 0 and LIM1.DRS = 1.
Transmit Line Interface (E1)
Transmitter Configuration (E1)
Recommended Transmitter Configuration Values (E1)
98
Characteristic Impedance [Ω]
120
7.5
1 : 2.4
1)
Functional Description E1
75
7.5
1 : 2.4
DS1.1, 2003-10-23
1)
PEF 2256 H/E
FALC
®
56