September 1999
PRELIMINARY
ML6411
Programmable Video Digitizer
with Selectable Gain and Clamps
GENERAL DESCRIPTION
The ML6411 is a Dual Video A/D converter, incorporating
two input sample and holds, two high speed 8-Bit A/D
converters, programmable gain control, selectable clamps,
multi-phase clocking, and reference voltage generation.
The ML6411 can be used to convert the following analog
signals to digital signals: two composite channels or S-
video channel.
All inputs are provided with appropriate input selectable
clamps to establish DC level. The clamps are full DC
restore circuits with the A-to-D converters in each
respective correction loop. The clamps are selectable to
16, 24, 64, and 128. The programmable gain control
provides various possibilities to select and adjust the gain
via two separate mechanisms: Sync-Suppressed Gain
Control (SGC ) for sync suppressed video such as RGB, and
User Gain Control (UGC) for video formats that require
scalable gain settings. Each of these can be programmed
through a serial bus.
FEATURES
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Complete video digitizer for Y/C and CV video
Contains A/D’s with scalable gain, selectable clamps,
and clock generation (programmable via serial bus)
Two 8-Bit +/- �½ LSB Differential Non-Linearity with
30MHz guaranteed conversion
Two Gain Control Mechanisms for programmable
or sync-suppressed video gain control
Selectable Video Clamping: 16, 24, 64, 128
Selectable Video Gain: 3dB to –6dB
Operating total power dissipation less than 425mW
Power down mode and Tri-state output control
Applications: Video Capture, Video Editing, Video
Cameras, Y/C and CV analog to digital conversion
44-pin TQFP
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BLOCK DIAGRAM
35
AVCC1
REF1
38
AVCC2
41
AVCC3
17
DVCC
15
VCCO
2
CLAMP
GATE
33
DGND
32
DVCC
18
RESET
23
OEA
11
OEB
39
VINN
44
CHANNEL A
36
Y/CV1
S/H
GAIN PRESET
SGC
SYNC SUPPRESS
GAIN CONTROL
UGC
USER GAIN
CONTROL
Y OR CV1
CHANNEL A
ADC
LATCH
Y/CV1
AOUT<7:0>
24:31
CHANNEL B
42
C/CV2
S/H
GAIN PRESET
SGC
SYNC SUPPRESS
GAIN CONTROL
UGC
USER GAIN
CONTROL
C OR CV2
CHANNEL B
ADC
LATCH
C/CV2
BOUT<7:0>
3:10
CLAMP
LEVEL
SELECT
CLPA<1:0>
CLPB<1:0>
SERIAL BUS
14
CLK
TIMING
GENERATOR
1
PD
19
SCLK
20
SDAT
CLKDIV
21
REFIN
22
REFOUT
12
VCC
37
AGNDI
40
AGND2
CV/S_MODE
STDA <1:0>
STDB <1:0>
GNA<5:0>
GNB<5:0>
BOOSTA
BOOSTB
APEAK
BPEAK
43
AGND3
13
GNDO
16
DGND
34
NC
1