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XRT86VL38
PRELIMINARY
xr
OCTAL T1/E1/J1 FRAMER/LIU COMBO
REV. P1.0.6
37
TRING0
TRING1
TRING2
TRING3
TRING4
TRING5
TRING6
TRING7
G4
H4
K4
L4
M4
P4
R4
U4
F1
J5
J1
L4
M3
P5
R2
U2
O
Transmit Negative Analog Output
TRING is the negative differential output to the line interface. This
output pin, along with the corresponding TTIP output pin, function as
the Transmit DS1/E1 output signal drivers for the XRT86VL38
device.
The user is expected to connect this signal and the corresponding
TRING output signal to a 1:2 step up transformer for proper opera-
tion.
Whenever the Transmit Section of the XRT86VL38 device generates
and transmits a “positive-polarity” pulse onto the line, this output pin
will be pulsed to a “lower-voltage” than its corresponding TTIP output
pins.
Conversely, whenever the Transmit Section of the XRT79L71 device
generates and transmit a “negative-polarity” pulse onto the line, this
output pin will be pulsed to a “higher-voltage” than that of the TTIP
output pins.
N
OTE
: This output pin will be tri-stated whenever the user sets the
“TxON” input pin or register bit (0xnF02, bit 3) to “0”.
TxON
Y3
W1
I
Transmitter On
This input pin permits the user to either enable or disable the Trans-
mit Output Driver within the Transmit DS1/E1 LIU Block. If the TxON
pin is pulled “Low”, all 8 Channels are tri-stated. When this pin is
pulled ‘High’, turning on or off the transmitters will be determined by
the appropriate channel registers (address 0x0Fn2, bit 3)
LOW
= Disables the Transmit Output Driver within the Transmit DS1/
E1 LIU Block. In this setting, the TTIP and TRING output pins of all 8
channels will be tri-stated.
HIGH
= Enables the Transmit Output Driver within the Transmit DS1/
E1 LIU Block. In this setting, the corresponding TTIP and TRING out-
put pins will be enabled or disabled by programming the appropriate
channel register. (address 0x0Fn2, bit 3)
N
OTE
: Whenever the transmitters are turned off , the TTIP and
TRING output pins will be tri-stated.
TIMING INTERFACE
S
IGNAL
N
AME
420 P
KG
B
ALL
#
484 P
KG
B
ALL
#
T
YPE
D
ESCRIPTION
MCLKIN
A4
A5
I
Master Clock Input:
This pin is used to provide the timing reference for the internal mas-
ter clock of the device. The frequency of this clock is programmable
from 8kHz to 16.384MHz in register 0x0FE9.
E1MCLKnOUT
B5
A4
O
LIU E1 Output Clock Reference
This output pin is defaulted to 2.048MHz, but can be programmed
to 4.096MHz, 8.192MHz, or 16.384MHz in register 0x0FE4.
TRANSMIT LINE INTERFACE
S
IGNAL
N
AME
420 P
KG
B
ALL
#
P
IN
#
T
YPE
D
ESCRIPTION