SAF7167AHWBR Philips, SAF7167AHWBR Datasheet - Page 7

• Manufacturer Part Number: SAF7167AHWBR
• Description: A/D, D/A Converters, Digital to Analog, ic, Semiconductors and Actives, dac
• Manufacturer: Philips

Philips Semiconductors
9397 750 12667
Product data sheet
7.1.2 YUV-to-RGB matrix
7.1.3 Triple 8-bit DACs
7.2 Analog mixers and keying control
Table 7:
For RGB 5 : 6 : 5 video inputs, the video data are just directly bypassed to triple DACs.
The input video data can be selected to either twos complement (I
binary offset (I
FMTC[1:0].
The rising edge of HREF input defines the start of active video data. When HREF is
inactive, the video output will be blanked.
The matrix converts YUV data, in accordance with ITU-R BT.601, to RGB data with
approximately 1.5 LSB deviation to the theoretical values for 8-bit resolution.
Three identical DACs for R, G and B video outputs are designed with voltage-drive
architecture to provide high-speed operation of up to 66 MHz conversion data rate. Pin
C_REF(H) is provided to allow for one external de-coupling capacitor to be connected
between the internal reference voltage source and ground.
The analog mixers are controlled to switch between the outputs from the video DACs and
analog RGB inputs by a keying signal. The analog RGB inputs need to interface with
analog mixers in the way of DC-coupling, also these RGB inputs are limited to RGB
signals without a sync level pedestal. The keying control can be enabled by setting
I
(from EXTKEY pin when KMOD[2:0] are all logic 0), and the other is the internal pixel
colour key (when KMOD[2:0] are not all logic 0) generated by comparing the input pixel
data with the internal I
are 4 ways to compare the pixel data (see
Input
UV0
YUV7
YUV6
YUV5
YUV4
YUV3
YUV2
YUV1
YUV0
RGB data
2
C-bus bit KEN = 1. Two kinds of keying are possible to generate: one is external key
Pixel byte sequence of 5 : 6 : 5
2
C-bus bit DRP = 1). The video input format is selected by I
Pixel byte sequence of RGB 5 : 6 : 5
G4
G3
G2
G1
B4
B3
B2
B1
B0
0
2
C-bus register value KD[7:0]. Controlled by KMOD[2:0] bits, there
Rev. 01 — 29 June 2004
G4
G3
G2
G1
B4
B3
B2
B1
B0
1
…continued
Table
YUV-to-RGB digital-to-analog converter
8).
G4
G3
G2
G1
B4
B3
B2
B1
B0
2
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
SAF7167AHW
2
C-bus bit DRP = 0) or
G4
G3
G2
G1
B4
B3
B2
B1
B0
3
2
C-bus bits
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