HMP8117
Data Sheet
January 1999
File Number
4643
NTSC/PAL Video Decoder
The HMP8117 is a high quality NTSC and PAL video
decoder with internal A/D converters. It is compatible with
NTSC M, PAL B, D, G, H, I, M, N, and combination N (N
C
)
video standards.
Both composite and S-video (Y/C) input formats are
supported. A 2-line comb filter plus a user-selectable
chrominance trap filter provide high quality Y/C separation.
User adjustments include brightness, contrast, saturation,
hue, and sharpness.
Vertical blanking interval (VBI) data, such as Closed
Captioning, Wide Screen Signalling and Teletext, may be
captured and output as BT.656 ancillary data. Closed
Captioning and Wide Screen Signalling information may also
be read out via the I
2
C interface.
The Videolyzer
™
feature provides approved Macrovision
™
copy-protection bypass and detection.
Features
• (M) NTSC and (B, D, G, H, I, M, N, N
C
) PAL Operation
- Optional Auto Detect of Video Standard
- ITU-R BT.601 (CCIR601) and Square Pixel Operation
• Videolyzer Feature
- Macrovision™ Bypass and Detection
• Digital Anti-Alias Filter
• Power Down Mode
• Digital Output Formats
- VMI Compatible
- 8-bit, 16-bit 4:2:2 YCbCr
- 15-bit (5,5,5), 16-bit (5,6,5) RGB
- Linear or Gamma-Corrected
- 8-bit BT.656
• Analog Input Formats
- Three Analog Composite Inputs
- Analog Y/C (S-video) Input
• “Raw” (Oversampled) VBI Data Capture
• “Sliced” VBI Data Capture Capabilities
- Closed Captioning
- Widescreen Signalling (WSS)
- BT.653 System B, C and D Teletext
- North American Broadcast Teletext (NABTS)
- World System Teletext (WST)
• 2-Line (1H) Comb Filter Y/C Separator
• Fast I
2
C Interface
Ordering Information
PART NUMBER
HMP8117CN
HMPVIDEVAL/ISA
NOTES:
1. PQFP is also known as QFP and MQFP.
2. Evaluation Board descriptions are in the Applications section.
TEMP RANGE
(
o
C)
0 to 70
PACKAGE
PACKAGE
NO.
80 Ld PQFP Q80.14x20
Evaluation Board: ISA Frame Grabber
Applications
• Multimedia PCs
• Video Conferencing
• Video Compression Systems
• Video Security Systems
• LCD Projectors and Overhead Panels
• Related Products
- NTSC/PAL Encoders: HMP815x, HMP817x, HMP819x
- NTSC/PAL Decoders: HMP8112A, HMP8115
1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
Videolyzer™ is a trademark of Intersil Corporation. Macrovision™ is a trademark of Macrovision Corporation.
http://www.intersil.com or 407-727-9207 | Copyright © Intersil Corporation 1999
Analog Front End Block Diagram
(EXTERNAL)
GAIN CONTROL
SET POINT
13
4 TO 13
DECODER
11
GAIN
CORRECTION
LOGIC
FINE ADJUST MULT. FACTOR
2.5V
Y
OUT
Y
IN
8
BUF
1.5V
1.75V
CHARGE PUMP
100µA
DISCHARGE
CHARGE
100µA
SYNC-TIP ENABLE
2.5V
A/D_TEST
2X
17
BUF
CHROMA
MULT.
LUMA
DC-RESTORE
LOGIC
DISABLE
MUX
SELECT
10-BIT 10
ADC
CORRECTION
MULTIPLIER
DIGITAL
ANTI-
ALIAS
FILTER
2X
9
EXTERNAL
ANTI-ALIAS
FILTER
Y[7:0]
LOW-PASS
FILTER
(REMOVE Fsc)
4
BACKPORCH
ENABLE
(INTERNAL CLAMP)
VAA
1.75V
TO
MUX
INPUT
VIDEO
1.0µF
nmos
+
-
75
CHROMA
ATTEN
(BELOW)
CHROMA MULT.
(BELOW)
#
PIN
50µA
VID1
1.0µF
CVBS1
7
CLAMP
3
M
U
X
13-STEP
VARIABLE
ATTENUATOR
CHROMA
ATTEN
13-STEP
VARIABLE
ATTENUATOR
2.0V
CHARGE PUMP
100µA
DISCHARGE
CHARGE
100µA
SYNC-TIP ENABLE
28
BIAS/
INTERNAL
REFERENCE
76
29
28
78
LCAP. DC-SIGNAL OFFSET ~= 2.4 VDC.
CCAP. DC-SIGNAL OFFSET ~= 2.4 VDC.
RSET. DC-SIGNAL OFFSET ~= 1.2 VDC.
REF_CAP. DC-SIGNAL OFFSET ~= 2.5 VDC.
78
10-BIT
10
ADC
VID2
1.0µF
CVBS2
6
CLAMP
8-BIT
TRUNCATE
Y_IN
1.0µF
CVBS3(Y)
5
CLAMP
75 75
75
1.75V
REF
LCAP
76
(OFFSET LUMA SIGNAL TO LOWER ADC REF ~= 1.5V)
STORAGE
CAP
0.1µF
CHROMA INPUT
HMP8117
C_IN
1.0µF
C
8-BIT
TRUNCATE
75
EXTERNAL
ANTI-ALIAS
FILTER
19
C[7:0]
(SIGNAL BIAS ~ 2.0V)
DIGITAL
ANTI-
ALIAS
FILTER
1.5V
DISABLE
CORRECTION
MULTIPLIER
CCAP
29
0.1µF
(OFFSET CHROMA SIGNAL TO ADC MID-SCALE ~= 2.0V)
CHROMA
DC-RESTORE
LOGIC
POWERDOWN
STORAGE
CAP
# DECODER PIN #
RSET
12.1K
REF_CAP
1.0µF
PIN #
NOMINAL (NTSC) OPERATING CONDITION
PIN # NOMINAL (NTSC) OPERATING CONDITION
5
6
7
CVBSX. SIZE = INPUT. SYNC TIP CLAMPED AT ~= 1.75 VDC.
9
8
Y
OUT
/Y
IN
. SIZE = ~1.0 V
P-P
, SYNC TIP OFFSET ~= 1.5 VDC.
19
C. SIZE = INPUT SIZE. PORCH OFFSET ~= 2.0 VDC.
17
A/D_TEST. SIZE ~= F(LUMA AGC), PORCH OFFSET ~= 2.0VDC.
HMP8117
Introduction
The HMP8117 is designed to decode baseband composite
or S-video NTSC and PAL signals, and convert them to
either digital YCbCr or RGB data. In addition to performing
the basic decoding operations, these devices include
hardware to decode different types of VBI data and to
generate full-screen blue, black and color bar patterns.
Digital PLLs are used to synchronize to all NTSC and PAL
standards. A chroma PLL is used to maintain color lock for
chroma demodulation while a line-locked PLL is used to
maintain vertical spatial alignment. The PLLs are designed
to maintain lock in the presence of VCR head switches, VCR
trick-mode and multi-path noise.
The HMP8117 provides the Videolyzer feature for
Macrovision (MV) copy-protection bypass and detection.
Digitization of Video
Prior to A/D conversion, the input signal is offset and scaled to
known video levels. After digitization, sample rate converters
and a comb filter are used to perform color separation and
demodulation.
A/D Conversion
Each CVBSX video input channel has a video clamp circuit
that is independent of PLL timing. The input clamp provides
a coarse signal offset to position the sync tip within the A/D
converter sampling range so that the AGC and DC-
RESTORE logic can operate.
A/D Conversion
Video data is sampled at the CLK2 frequency then processed
by the input sample rate converter. The output levels of the
ADC after AGC and DC restoration processing are:
(M) NTSC
(M, N) PAL
white
black
blank
sync
196
66
56
0
(B, D, G, H, I, N
C
)
PAL
196
59
59
0
External Video Processing
Before a video signal can be digitized the decoder has some
external processing considerations that need to be
addressed. This section discusses those external aspects of
the HMP8117.
Analog Video Inputs
The HMP8117 supports either three composite or two
composite and one S-video input.
Three analog video inputs (CVBS 1-3) are used to select
which one of three composite video sources are to be
decoded. To support S-video applications, the Y channel
drives the CVBS3(Y) analog input, and the C channel drives
the C analog input.
The analog inputs must be AC-coupled to the video signals,
as shown in the Applications section.
AGC and DC Restoration
The AGC amplifier attenuates or amplifies the analog video
signal to ensure that the blank level generates code 56 or 59
depending on the video standard. The difference from the
ideal blank level of 56 or 59 is used to control the amount of
attenuation or gain of the analog video signal. To obtain a
stable DC reference for the AGC, a digital low-pass filter
removes the chroma burst from the input signal’s backporch.
DC restoration positions the video signal so that the sync tip
generates a code 0. The internal timing windows for AGC
and DC restoration are show in Figure 3. The appropriate
windows are automatically determined by the decoder when
the input signal is auto-detected or manually selected.
Anti-alias Filters
Although a 23 tap digital halfband anti-alias filter is provided
for each A/D channel, an external passive filter is
recommended for optimum performance. The digital filter
has a flat response out to 5.4MHz with an approximate -3dB
bandwidth of 6.3MHz using a 27MHz input CLK2 sample
rate. For the CVBSx inputs, the filter is connected between
the YOUT and YIN pins. For the C (chroma) input, the anti-
alias filter should be connected before the C input.
Recommended filter configurations are shown on the
reference schematic in Figure 20. These filters have flat
response out to 4.2MHz with an approximate -3dB
bandwidth of 8MHz. If upgrading from the HMP8115 or
HMP8112A, the previous filter configurations may be used
but with slightly degraded bandwidth. Alternative higher or
lower performance filters configurations may substituted.
VIDEO INPUT
AGC
DC RESTORE
FIGURE 1. AGC AND DC RESTORE INTERNAL TIMING
5
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