PEF24901HV22XT Lantiq, PEF24901HV22XT Datasheet - Page 66

• Manufacturer Part Number: PEF24901HV22XT
• Manufacturer: Lantiq

Specifications of PEF24901HV22XT

• Control Interface: HDLC
• Lead Free Status / Rohs Status: Compliant

• as the internal control logic of the activation/deactivation procedures is event driven
Regarding a connected AFE power down mode means that
• no signal (signal U0) is sent on the U-interface
• only functions that are necessary to detect the wake up conditions are kept active
• transmit path, receive path and auxiliary functions of the analog line port are switched
• the ADC, the relevant output is tied to GND.
• the DAC and the output buffer; the outputs AOUTx/ BOUTx are tied to GND.
• the internal DC voltage reference is switched off.
• the range and the loop functions are deactivated.
4.3
This chapter illustrates the interactions during activation and deactivation between the
LT and NT station. An activation can be initiated by either of the two stations involved. A
deactivation procedure can be initiated only by the exchange. The status of a
transmission line is classified by one of the seven activation/deactivation states (also
referred to by number in the activation/ deactivation procedures on the following sides):
1. Activation States:
2. Transparent State:
3. Deactivation States:
The transmission link is totally deactivated thereafter.
Data Sheet
power is saved as soon as one of the four lines transits in the DEACTIVATED state
to a low power consuming mode when the power down function is activated. This
implies the following:
1.1 Line awake
1.2 Synchronization downstream
1.3 Synchronization upstream
1.4 Synchronized
In the activated state, the user data is transmitted from exchange to TE and vice versa.
Deactivation is done in two steps on each individual line separately.
3.1 Deactivation request downstream
3.2 Deactivation acknowledge upstream
Each individual line is being awoken, but is not yet synchronized, data
transmission is not yet possible
Synchronization is always done downstream first, the whole line has to
synchronize on the exchange
Because the delay differs from line to line, bit synchronization is necessary in the
LT
All layer-1 units of the link are told by the exchange that synchronization has been
finished
Layer 1 Activation/ Deactivation Procedures
67
Operational Description
PEF 24901
2002-09-30
DFE-T