peb2256 Infineon Technologies Corporation, peb2256 Datasheet - Page 61

• Manufacturer Part Number: peb2256
• Description: E1/t1/j1 Framer And Line Interface Component For Long And Short Haul Applications
• Manufacturer: Infineon Technologies Corporation

4.1.3
The FALC56 automatically recovers the signals received on pins RL1/2 in a range of up
to -43 dB. The maximum reachable length with a 22 AWG twisted pair cable is 1500 m.
After reset the FALC56 is in short-haul“ mode, received signals are recovered up to -10
dB of cable attenuation. Switching in Long-haul“ mode is done by setting of bit
LIM0.EQON.
The integrated receive equalization network recovers signals with up to -43 dB of cable
attenuation. Noise filters eliminate the higher frequency part of the received signals. The
incoming data is peak-detected and sliced to produce the digital data stream. The slicing
level is software selectable in four steps (45%, 50%, 55%, 67%). For typical E1
applications, a level of 50% is used. The received data is then forwarded to the clock &
data recovery unit.
In long-haul mode, the current equalizer status is indicated by register RES (Receive
Equalizer Status).
4.1.4
Status register RES reports the current receive line attenuation in a range from 0 to -43
dB in 25 steps of approximately 1.7 dB each. The least significant 5 bits of this register
indicate the cable attenuation in dB. These 5 bits are only valid in combination with the
most significant two bits (RES.EV1/0 = 01).
4.1.5
The analog received signal on port RL1/2 is equalized and then peak-detected to
produce a digital signal. The digital received signal on port RDIP/N is directly forwarded
to the DPLL. The receive clock and data recovery extracts the route clock from the data
stream received at the RL1/2, RDIP/RDIN or ROID lines and converts the data stream
into a single-rail, unipolar bit stream. The clock and data recovery uses an internally
generated high frequency clock based on MCLK.
The recovered route clock or a de-jittered clock can be output on pin RCLK as shown in
Table
See also
Data Sheet
10.
Table 13
Receive Equalization Network (E1)
Receive Line Attenuation Indication (E1)
Receive Clock and Data Recovery (E1)
on page
67
for details of master/slave clocking.
61
Functional Description E1
FALC56 V1.2
PEB 2256
2002-08-27