pef22504 Infineon Technologies Corporation, pef22504 Datasheet - Page 132

• Manufacturer Part Number: pef22504
• Description: Quad E1/t1/j1 Line Interface Component For Long- And Short-haul Applications Pef 22504 E, Pef 22504 Ht, Version 2.1
• Manufacturer: Infineon Technologies Corporation

Transmit Pulse Mask 0
See
pins XL1 and XL2. The level of the pulse shape can be programmed by registers XPM(2:0) if XPM2.XPDIS is set
to ´0´ to create a custom waveform. If XPM2.XPDIS is set to ´1´, the custom waveform can be programed by the
registers TXP(16:1) and the register bits of XPM(2:0) are unused with exception of the bits XPM2.XLT,
XPM2.DAXLT and XPM2.XPDIS. In order to get an optimized pulse shape for the external transformers each
pulse shape is internally divided into four sub pulse shapes if XPM2.XPDIS is set to ´0´. In each sub pulse shape
a programmed 5-bit value defines the level of the analog voltage on pins XL1/2. Together four 5-bit values have
to be programmed to form one complete transmit pulse shape. The four 5-bit values are sent in the following
sequence:
XP04 to 00: First pulse shape level
XP14 to 10: Second pulse shape level
XP24 to 20: Third pulse shape level
XP34 to 30: Fourth pulse shape level
Changing the LSB of each subpulse in registers XPM(2:0) changes the amplitude of the differential voltage on
XL1/2 by approximately 80 mV. Recommended values for standard applications are given in Table 22 and
Table 23.
Note that in the special cases were the LBO pulse masks are performed in T1 mode, the programming of the pulse
masks is done internally, independent on the settings in XPM(2:0).
XPM0
Transmit Pulse Mask0
Field
XP12
XP11
XP10
XP04
XP03
XP02
XP01
XP00
Data Sheet
Chapter 3.9.6.1
Bits
7
6
5
4
3
2
1
0
and
Chapter
Type
rw
rw
rw
rw
rw
rw
rw
rw
3.9.6.2. The transmit pulse shape which is defined in ITU-T G.703 is output on
Description
Bit 2 of second pulse shape level
Bit 1 of second pulse shape level
Bit 0 (LSB) of second pulse shape level
Bit 4 (MSB) of first pulse shape level
Bit 3 of first pulse shape level
Bit 2 of first pulse shape level
Bit 1 of first pulse shape level
Bit 0 (LSB) of first pulse shape level
Offset
xx26
132
H
Register DescriptionTransmit Pulse Mask 0
Rev. 1.3, 2006-01-25
QuadLIU
PEF 22504
Reset Value
7B
TM
H