DS26303L-XXX DALLAS [Dallas Semiconductor], DS26303L-XXX Datasheet - Page 66

• Manufacturer Part Number: DS26303L-XXX
• Description: 3.3V, E1/T1/J1, Short-Haul, Octal Line Interface Unit
• Manufacturer: DALLAS [Dallas Semiconductor]

Figure 6-9. Digital Loopback
6.8.3
The inputs at RTIPn and RRINGn are looped back to TTIPn and TRINGn. The inputs at TPOSn, and TNEGn are
ignored during a remote loopback. While the TCLKn pin is ignored in remote loopback mode for the data path, the
TCLKn pin must have an active signal applied in order to keep the transmitter operational. See the TCLKn pin
description for details. This loopback is conceptually shown in
Figure 6-10. Remote Loopback
Remote Loopback
TCLK
TCLK
TNEG
TNEG
TPOS
TPOS
RNEG
RNEG
RCLK
RPOS
RCLK
RPOS
H D B 3 /
B 8 Z S
D e c o d e r
H D B 3 /
B 8 Z S
D e c o d e r
H D B 3 /
B 8 Z S
E n c o d e r
H D B 3 /
B 8 Z S
E n c o d e r
O p t i o n a l
J i t t e r
A t t e n u a t o r
O p t i o n a l
J i t t e r
A t t e n u a t o r
O p t i o n a l
J i t t e r
A t t e n u a t o r
O p t i o n a l
J i t t e r
A t t e n u a t o r
DS26303: 3.3V, T1/E1/J1, Short-Haul, Octal Line Interface Unit
66 of 101
T r a n s m i t
D i g i t a l
T r a n s m i t
D i g i t a l
R e c e i v e
D i g i t a l
R e c e i v e
D i g i t a l
Figure
6-10.
T r a n s m i t
A n a l o g
T r a n s m i t
A n a l o g
R e c e i v e
A n a l o g
R e c e i v e
A n a l o g
Line
Driver
Line
Driver
RRING
RRING
RTIP
RTIP
TPOS
TPOS
TNEG
TNEG