PEF80912HV14NP Lantiq, PEF80912HV14NP Datasheet - Page 38

• Manufacturer Part Number: PEF80912HV14NP
• Manufacturer: Lantiq

Specifications of PEF80912HV14NP

• Lead Free Status / Rohs Status: Supplier Unconfirmed

2.3.6
For North American applications a maintenance controller according to ANSI T1.601
section 6.5 is implemented. The maintenance pulse stream from the U-interface Metallic
Loop Termination circuit (MLT) is fed to pin MTI, usually via an optocoupler. It is digitally
filtered for 20 ms and decoded independently on the polarity by the maintenance
controller according to
detecting the DC and AC signaling format. The Q-SMINT
transceiver in the proper state and issues an interrupt. The state selected by the MLT is
indicated via two bits.
The Q-SMINT
transceiver state. This includes the power-down state.
A test mode is valid for 75 seconds. If during the 75 seconds a valid pulse sequence is
detected the 75 s timer starts again. After expiry of the 75 s timer the MLT maintenance
controller goes back to normal operation.
•
Table 13
Number of
counted pulses
<= 5
6
7
8
9
10
>= 11
Figure 11
Data Sheet
shows examples for pulse streams with inverse polarity selecting Quiet Mode.
Metallic Loop Termination
ANSI Maintenance Controller States

O reacts on a valid pulse stream independently of the current U-
ANSI maintenance
controller state
ignored
Quiet Mode
ignored
Insertion Loss Measurement transition to state ’Transparent’
ignored
normal operation
ignored
Table
13. Therefore, the maintenance controller is capable of
30
U-transceiver State Machine
no impact
transition to state ’Reset’
start timer 75s
no impact
start timer 75s
no impact
transition to state ’Reset’
no impact

O automatically sets the U-
Functional Description
PEF 80912/80913
2001-03-29