MH88634
TIP
RING
XLA
XLD
XLB
XLC
IC
IC
IC
SHK
Rx
VEE
Tx
RV
FL
RL
VDD
AGND
LRC
VRLY
LRD
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
Preliminary Information
Figure 2 - Pin Connections
Pin Description
Pin #
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Name
TIP
RING
XLA
XLD
XLB
XLC
IC
IC
IC
SHK
Rx
VEE
Tx
RV
Description
Tip Lead:
Connects to the “Tip” lead of the central office
Ring Lead:
Connects to the “Ring” lead of the central office
Loop Relay Contact A:.
Connects to XLB through the Loop relay (K1) contacts when the
relay is activated. This operates the internal active termination circuitry.
Loop Relay Contact D:
See XLC for description
Loop Relay Contact B:
See XLA for description
Loop Relay Contact C:
Connects to XLD through the loop relay (K1) contacts when the
relay is activated. This operates the internal active termination circuitry.
Internal Connection:
This pin is internally connected and must be left open.
Internal Connection.:
This pin is internally connected and must be left open.
Internal Connection:
This pin is internally connected and must be left open.
Switch Hook (Output).
A logic low indicates either forward or reverse loop current.
Receive (Input):
4-Wire ground (AGND) referenced audio input.
Negative Supply Voltage.
-5V
Transmit (Output).
4-Wire ground (AGND) referenced audio output.
Ring Voltage Detect (Output).
A logic low indicates that ringing voltage is across the Tip
and Ring leads. Note that this output toggles at the ringing cadence and not at the ringing
frequency.
Forward Loop Detect (Output):
In the on-hook state, a logic low output indicates that
forward loop battery is present. In the off-hook state, a logic low indicates that forward loop
current is present.
Reverse Loop Detect (Output).
In the on-hook state, a logic low output indicates that
reverse loop battery is present. In the off-hook state, a logic low output indicates that
reverse loop current is present. Reverse loop refers to the Tip lead negative respect to the
Ring Lead.
Positive Supply Voltage:
+5V
15
FL
16
RL
17
2-254
VDD
MITEL [ MITEL NETWORKS CORPORATION ]
