
DS26518 8-Port T1/E1/J1 Transceiver
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8.
PIN DESCRIPTIONS
8.1
Pin Functional Description
Table 8-1. Detailed Pin Descriptions
NAME
PIN
TYPE
FUNCTION
ANALOG TRANSMIT
TTIP1
A1, A2
TTIP2
H1, H2
TTIP3
J1 J2
TTIP4
T1, T2
TTIP5
T15, T16
TTIP6
J15, J16
TTIP7
H15, H16
TTIP8
A15, A16
Analog
Output,
High
Impedance
Transmit Bipolar Tip for Transceiver 1 to 8. These pins are differential line
driver tip outputs. These pins can be high impedance if:
If TXENABLE is low, TTIPn/TRINGn will be high impedance. Note that if
TXENABLE is low, the register settings for control of TTIPn/TRINGn are ignored
and output is high impedance.
The differential outputs of TTIPn and TRINGn can provide internal matched
impedance for E1 75
Ω, E1 120Ω, T1 100Ω, or J1 110Ω. The user can turn off
internal termination.
Note: The two pins shown for each transmit bipolar tip (e.g., pins A1 and A2 for
TTIP1) should be tied together.
TRING1
A3, B3
TRING2
G3, H3
TRING3
J3, K3
TRING4
R3, T3
TRING5
R14,T14
TRING6
J14, K14
TRING7
G14, H14
TRING8
A14, B14
Analog
Output,
High
Impedance
Transmit Bipolar Ring for Transceiver 1 to 8. These pins are differential line
driver ring outputs. These pins can be high impedance if:
If TXENABLE is low, TTIPn/TRINGn will be high impedance. Note that if
TXENABLE is low, the register settings for control of TTIPn/TRINGn are ignored
and output is high impedance.
The differential outputs of TTIPn and TRINGn can provide internal matched
impedance for E1 75
Ω, E1 120Ω, T1 100Ω, or J1 110Ω. The user can turn off
internal termination.
Note: The two pins shown for each transmit bipolar ring (e.g., pins A3 and B3 for
TRING1) should be tied together.
TXENABLE/
SCAN_EN
L13
Input
Transmit Enable. If this pin is pulled low, all transmitter outputs (TTIPn and
TRINGn) are high impedance. The register settings for tri-state control of
TTIPn/TRINGn are ignored if TXENABLE is low. If TXENABLE is high, the
particular driver can be tri-stated by the register settings.
Scan Enable. When low, device is in normal operation. Scan enable is selected
by the SCANMODE pin. Note: User should not select scan enable—test mode
only.
ANALOG RECEIVE
RTIP1
C1
RTIP2
F1
RTIP3
L1
RTIP4
P1
RTIP5
P16
RTIP6
L16
RTIP7
F16
RTIP8
C16
Analog
Input
Receive Bipolar Tip for Transceiver 1 to 8. The differential inputs of RTIPn
and RRINGn can provide internal matched impedance for E1 75
Ω, E1 120Ω, T1
100
Ω, or J1 110Ω. The user can turn off internal termination via the LIU Receive
Impedance and Sensitivity Monitor register (
LRISMR).RRING1
C2
RRING2
F2
RRING3
L2
RRING4
P2
RRING5
P15
RRING6
L15
RRING7
F15
RRING8
C15
Analog
Input
Receive Bipolar Ring for Transceiver 1 to 8. The differential inputs of RTIPn
and RRINGn can provide internal matched impedance for E1 75
Ω, E1 120Ω, T1
100
Ω, or J1 110Ω. The user has the option of turning off internal termination via
the LIU Receive Impedance and Sensitivity Monitor register
(LRISMR).
RESREF
J5
Input
Resistor Reference. This pin is used to calibrate the internal impedance match
resistors of the receive LIUs. This pin should be tied to VSS through a 10kΩ ±1%
resistor.