SAA7154E/V2/G NXP Semiconductors, SAA7154E/V2/G Datasheet - Page 17

• Manufacturer Part Number: SAA7154E/V2/G
• Manufacturer: NXP Semiconductors

Specifications of SAA7154E/V2/G

• Adc/dac Resolution: 10b
• Screening Level: Commercial
• Package Type: LBGA
• Pin Count: 156
• Lead Free Status / RoHS Status: Compliant

NXP Semiconductors
SAA7154E_SAA7154H_2
Product data sheet
7.1.1.2 Buffered analog output
7.1.2.1 Block description
7.1.2 Analog input control
Fast blanking (RGB switch control):
basis either a CVBS or a RGB signal (which is usually menu information or teletext
synchronized with CVBS). Since the switch control signal is generally at a different clock
rate than the system clock (although both are line-locked), the sampling instance for this
signal sometimes might show some uncertainties if a standard bi-level input is used.
The SAA7154E; SAA7154H digitizes the switching signal with 3-bit at a 54 MHz system
clock, thus reproducing its transient exactly; the digitized information is used to control a
digital fader, resulting in a correctly weighted CVBS and RGB portion at every switching
point.
Activity on the fast blanking signal is monitored continuously and reflected in a dedicated
I
can occur during text overlay,
The existing SAA7118 provides one out of four selected input signals (used for further
digital processing) at a buffered output, but the SAA7154E; SAA7154H is also able to
point to any two out of eight analog inputs (which the digital processing unit accepts, if
necessary). Additionally, the second buffered output signal might be the summation of an
input Y and C signal, thus easily converting these signals to CVBS.
For example this buffered output signal can be fed to a teletext decoder such as the
SAA5264/65 or it can serve as a CVBS monitoring signal to a video recorder.
The Analog Input Control (AIC) has the following key features:
The SAA7154E; SAA7154H provides sixteen analog signal inputs, four analog main
channels with source switch, clamp circuit, analog amplifier and video 10-bit CMOS ADC.
The gain control circuit receives the static gain levels for the four analog amplifiers
(through the I
Automatic Gain Control (AGC) as part of the Analog Input Control (AIC). This AGC for
luminance is used to amplify a CVBS or Y signal to the required signal amplitude,
matched to the ADCs input voltage range. It is not possible to apply AGC to component
input signals, therefore the gain of these signals has to be set manually using the
corresponding control registers.
2
C-bus status bit; the SAA7154E; SAA7154H recognizes even short switch pulses that
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Fully autonomous video gain and clamp control, based on analog (coarse) gain
pre-scaling and digital (fine) gain control in CVBS mode
Adaptive (master-slave) mode: manual gain control for Y/C input signals
Component input signals (sync RGB, Y-C
Access to various special controls like status signals for debugging (expert mode)
SAA7118 backward-compatible input mode table with user presets
Clamp: gain correction of input signals containing Macrovision copy protection
Gain correction for compressed-sync (white peak) events
Integrated decimation filters for 4 : 1 (SDTV) and 2 : 1 (HDTV) oversampling modes.
2
C-bus) or controls one of these amplifiers automatically through a built-in
Rev. 02 — 6 December 2007
The RGB switch control selects on a pixel-by-pixel
SAA7154E; SAA7154H
Multistandard video decoder with comb filter
B
-C
R
) based on manual gain control
© NXP B.V. 2007. All rights reserved.
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