PEF22827EL-V11 Lantiq, PEF22827EL-V11 Datasheet - Page 78

• Manufacturer Part Number: PEF22827EL-V11
• Manufacturer: Lantiq

Specifications of PEF22827EL-V11

• Lead Free Status / RoHS Status: Supplier Unconfirmed

5.5.2
The Post Tuning Filter (POFI) is a third order Chebyshev filter with a programmable
corner frequency. See
description about programming the corner frequency. No external filter is required.
5.5.3
In order to comply with required PSD masks, a power control unit optimizes the
transmission power. Furthermore, the digital transceiver’s PBO algorithm controls the
power for different loop lengths. See
description about power control gain programming.
In the upstream direction, a VDSL modem located near the cabinet causes strong far
end crosstalk (FEXT). In this case the power control unit and PBO mechanism may be
used to reduce power in small increments. Power management functionality enables the
modem to optimize power for balanced performance between the upstream and
downstream transmissions while reducing FEXT between systems.
5.6
The receive path of the Analog Block includes an Automatic Gain Control (AGC) unit, a
Prefilter (PREFI) and an Analog to Digital Converter (ADC) unit.
5.6.1
The signal power at the ADC input depends on the transmission line length. The AGC
adapts the signal to the ADC range. The digital transceiver’s internal processor controls
the AGC circuit. The dynamic range of the AGC is from -12 to 32.5 dB in increments of
0.5 dB. See
information about programming the AGC register.
5.6.2
The transmission channel attenuates higher frequencies more than lower frequencies.
The analog channel equalizer raises the higher transmission frequencies to compensate
for the receive signal.
5.6.3
The PREFI performs anti-aliasing for the modem and has the same characteristics as
the post filter (POFI). See
5.6.4
The ADC has a resolution of 12 bits and an analog bandwidth of 12 MHz.
Preliminary Data Sheet
Post Tuning Filter (POFI)
Power Controller
Receive Path
Automatic Gain Control (AGC)
Analog Channel Equalizer
Pre-Tuning Filter
Analog-to-Digital Converter (ADC)
“ACE, Measurement Buffer and AGC Mode” on Page 257
“Corner Frequency and Tuning” on Page 261
“Post Tuning Filter (POFI)” on Page
“Power Control” on Page 258
78
Functional Description – Analog Block
78.
Rev. 1.1, 2005-01-30
for a complete
for a complete
VDSL6100i
PEF 22827
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