TZA1038HW,118 NXP Semiconductors, TZA1038HW,118 Datasheet - Page 9

• Manufacturer Part Number: TZA1038HW,118
• Description: IC DVD SIGNAL PROC 48-HTQFP
• Manufacturer: NXP Semiconductors

Specifications of TZA1038HW,118

• Applications: *
• Mounting Type: Surface Mount
• Package / Case: 48-TQFP Exposed Pad, 48-eTQFP, 48-HTQFP, 48-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 935273843118; TZA1038HW-T; TZA1038HW-T

Philips Semiconductors
7
7.1
The RF data path is a fully DC-coupled, multi-stage
amplifier (see Fig.3). The input signal for data can be
selected from RF inputs A to D or from the summed
RF inputs RFSUMP and RFSUMN. Switching between the
two sets of signals is performed by an internal multiplexer.
The signals are fully balanced internally to improve signal
quality and reduce power supply interference.
RF outputs RFP and RFN can be DC coupled to the
Analog-to-Digital Converter (ADC) of the decoder.
The RF input signals are from photodiodes and have
a large DC content by nature. This DC component must be
removed from the signals for good system performance.
Built-in DACs, located after the input stages
G
and resolution is scaled with the gain setting of the first
amplifier stage. When the DC content is removed, the
RF signal can be DC coupled to the decoder. The main
advantage of DC coupling is fast recovery from signal
swings due to disc defects since there is no AC coupling
capacitance to slow the recovery. When using DC
coupling, both AC and DC content in the data signal is
known. The Philips Iguana decoders have on-chip control
loops to support Automatic Gain Control (AGC) and DC
cancellation.
Two separate DACs are available for cases where the left
and right side DC conditions can be different.
2003 Sep 03
1
High speed advanced analog DVD signal
processor and laser supply
and RFSUM, have the ability to do this. The DAC range
FUNCTIONAL DESCRIPTION
RF data processing
9
When it is not possible to have a DC connection between
the TZA1038HW and the decoder, the signals on servo
outputs OA to OD can be used as they contain the same
LP-filtered and DC coupled information.
Summing of the photodiode signals A to D is performed in
the second amplifier stage G
channel can be switched on, off or inverted with switches
SW-A to SW-D.
Switching between photodiode signals and RFSUM input
is performed immediately before the third amplifier
stage G
resolution to allow automatic gain adjustment to be
controlled by the decoder.
The filter stage limits the bandwidth according to the
maximum playback speed of the disc. This is to optimize
the noise performance. The filter stage consists of an
equalizer and a noise filter, both of which can be
bypassed, also the boost factor of the equalizer can be set.
The corner frequencies of the equalizer and noise filter are
equal and can be programmed to a 7-bit resolution.
The RF output signals RFP and RFN can be DC coupled
to a decoder with a differential input pair (as with Philips
Iguana decoders). The common mode output voltage can
be set externally at pin RFREF.
The signals for differential phase detection are tapped
from the inputs A to D at the RF amplifier G
DC cancellation for the A to D and RFSUM signal paths
can be set independently or simultaneously.
3
. This stage has a variable gain with fine
2
. Each individual diode
TZA1038HW
Product specification
1
stages.