XRT83L34_05 Datasheet, PDF (26/99 Pages) Exar Corporation – QUAD T1/E1/J1 LH/SH TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR

XRT83L34
xr
REV. 1.0.1 QUAD T1/E1/J1 LH/SH TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
SIGNAL NAME
EQC4
EQC3
EQC2
EQC1
EQC0
A[4]
A[3]
A[2]
A[1]
A[0]
RXTSEL
PIN #
59
60
61
62
63
59
60
61
62
63
110
TYPE
I
I
DESCRIPTION
Equalizer Control Input 4 - Hardware Mode
This pin together with EQC[3:0] are used for controlling the transmit pulse
shaping, transmit line build-out (LBO), receive monitoring and also to select
T1, E1 or J1 Modes of operation. See Table 4 for description of Transmit
Equalizer Control bits.
Equalizer Control Input 3
Equalizer Control Input 2
Equalizer Control Input 1
Equalizer Control Input 0
NOTES:
1. In Hardware mode all transmit channels share the same pulse
setting controls function.
2. All channels of an XRT83L34 must operate at the same clock rate,
either the T1, E1 or J1 modes.
Microprocessor Address bits [4:0] - Host Mode
See “Address Bus Input Pins/Jitter Attenuator Select Input Pins/
Equalizer Control Input pins:” on page 18.
NOTE: Internally pulled “Low” with a 50kΩ resistor for all channels.
Receiver Termination Select
In Hardware mode, when this pin is “Low” the receive line termination is
determined only by the external resistor. When “High”, the receive termina-
tion is realized by internal resistors or the combination of internal and exter-
nal resistors. These conditions are described in the table below.
NOTE: In Hardware mode all channels share the same RXTSEL control
function.
RXTSEL
0
1
RX Termination
External
Internal
TXTSEL
In Host mode, the RXTSEL_n bits in the channel control registers deter-
mines if the receiver termination is external or internal. However the function
of RXTSEL can be transferred to the Hardware pin by setting the TERCNTL
bit (bit 4) to “1” in the register 66 address hex 0x42.
NOTE: Internally pulled “Low” with a 50kΩ resistor.
111
I
Transmit Termination Select - Hardware Mode
When this pin is “Low” the transmit line termination is determined only by an
external resistor. When “High”, the transmit termination is realized only by
the internal resistor.
TXTSEL TX Termination
0
External
1
Internal
NOTES:
1. This pin is internally pulled "Low" with a 50kΩ resistor.
2. In Hardware Mode all channels share the same TXTSEL control
function.
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