전자부품 데이터시트 검색엔진
  Korean  ▼
ALLDATASHEET.CO.KR

X  

ADV7122 데이터시트(PDF) 10 Page - Analog Devices

부품명 ADV7122
상세설명  CMOS 80 MHz, Triple 10-Bit Video DACs
Download  12 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
제조업체  AD [Analog Devices]
홈페이지  http://www.analog.com
Logo AD - Analog Devices

ADV7122 데이터시트(HTML) 10 Page - Analog Devices

Back Button ADV7122_15 Datasheet HTML 4Page - Analog Devices ADV7122_15 Datasheet HTML 5Page - Analog Devices ADV7122_15 Datasheet HTML 6Page - Analog Devices ADV7122_15 Datasheet HTML 7Page - Analog Devices ADV7122_15 Datasheet HTML 8Page - Analog Devices ADV7122_15 Datasheet HTML 9Page - Analog Devices ADV7122_15 Datasheet HTML 10Page - Analog Devices ADV7122_15 Datasheet HTML 11Page - Analog Devices ADV7122_15 Datasheet HTML 12Page - Analog Devices  
Zoom Inzoom in Zoom Outzoom out
 10 / 12 page
background image
ADV7121/ADV7122
–10–
REV. B
More detailed information regarding load terminations for vari-
ous output configurations, including RS-343A and RS-170, is
available in an Application Note entitled “Video Formats &
Required Load Terminations” available from Analog Devices,
publication no. E1228–15–1/89.
Figure 3 shows the video waveforms associated with the three
RGB outputs driving the doubly terminated 75
Ω load of Fig-
ure 5a. As well as the gray scale levels, Black Level to White
Level, the diagram also shows the contributions of SYNC and
BLANK
for the ADV7122. These control inputs add appropri-
ately weighted currents to the analog outputs, producing the
specific output level requirements for video applications.
Table Ia. details how the SYNC and BLANK inputs modify
the output levels.
Gray Scale Operation
The ADV7121/ADV7122 can be used for stand-alone, gray
scale (monochrome) or composite video applications (i.e., only
one channel used for video information). Any one of the three
channels, RED, GREEN or BLUE can be used to input the
digital video data. The two unused video data channels should
be tied to logical zero. The unused analog outputs should be
terminated with the same load as that for the used channel. In
other words, if the red channel is used and IOR is terminated
with a doubly terminated 75
Ω load (37.5 Ω), IOB and IOG
should be terminated with 37.5
Ω resistors. See Figure 6.
GND
ADV7121/ADV7122
R0
R9
G0
G9
B0
B9
VIDEO
INPUT
DOUBLY
TERMINATED
75
Ω LOAD
IOR
IOG
IOB
37.5
37.5
Figure 6. Input and Output Connections for Stand-Alone
Gray Scale or Composite Video
Video Output Buffers
The ADV7121/ADV7122 is specified to drive transmission line
loads, which is what most monitors are rated as. The analog
output configurations to drive such loads are described in the
Analog Interface section and illustrated in Figure 5. However,
in some applications it may be required to drive long “transmis-
sion line” cable lengths. Cable lengths greater than 10 meters
can attenuate and distort high frequency analog output pulses.
The inclusion of output buffers will compensate for some cable
distortion. Buffers with large full power bandwidths and gains
between 2 and 4 will be required. These buffers will also need
to be able to supply sufficient current over the complete output
voltage swing. Analog Devices produces a range of suitable op
amps for such applications. These include the AD84x series of
monolithic op amps. In very high frequency applications (80 MHz),
the AD9617 is recommended. More information on line driver
buffering circuits is given in the relevant op amp data sheets.
Use of buffer amplifiers also allows implementation of other
video standards besides RS-343A and RS-170. Altering the gain
components of the buffer circuit will result in any desired video
level.
DACs
Z
O = 75Ω
(CABLE)
Z
S = 75Ω
(SOURCE
TERMINATION)
AD848
+V
S
0.1
µF
0.1
µF
IOR, IOG, IOB
75
2
7
6
4
3
Z
1
Z
L = 75Ω
(MONITOR)
Z
1
Z
2
GAIN (G) = 1+ ––
–V
S
Z
2
Figure 7. AD848 As an Output Buffer
PC Board Layout Considerations
The ADV7121/ADV7122 is optimally designed for lowest noise
performance, both radiated and conducted noise. To comple-
ment the excellent noise performance of the ADV7121/ADV7122
it is imperative that great care be given to the PC board layout.
Figure 8 shows a recommended connection diagram for the
ADV7121/ADV7122.
The layout should be optimized for lowest noise on the
ADV7121/ADV7122 power and ground lines. This can be
achieved by shielding the digital inputs and providing good de-
coupling. The lead length between groups of VAA and GND
pins should by minimized so as to minimize inductive ringing.
Ground Planes
The ADV7121/ADV7122 and associated analog circuitry,
should have a separate ground plane referred to as the analog
ground plane. This ground plane should connect to the regular
PCB ground plane at a single point through a ferrite bead, as il-
lustrated in Figure 8. This bead should be located as close as
possible (within 3 inches) to the ADV7121/ADV7122.
The analog ground plane should encompass all ADV7121/
ADV7122 ground pins, voltage reference circuitry, power sup-
ply bypass circuitry, the analog output traces and any output
amplifiers.
The regular PCB ground plane area should encompass all the
digital signal traces, excluding the ground pins, leading up to
the ADV7121/ADV7122.
Power Planes
The PC board layout should have two distinct power planes,
one for analog circuitry and one for digital circuitry. The analog
power plane should encompass the ADV7121/ADV7122 (VAA)
and all associated analog circuitry. This power plane should be
connected to the regular PCB power plane (VCC) at a single
point through a ferrite bead, as illustrated in Figure 8. This bead
should be located within three inches of the ADV7121/ADV7122.
The PCB power plane should provide power to all digital logic
on the PC board, and the analog power plane should provide
power to all ADV7121/ADV7122 power pins, voltage reference
circuitry and any output amplifiers.
The PCB power and ground planes should not overlay portions
of the analog power plane. Keeping the PCB power and ground
planes from overlaying the analog power plane will contribute to
a reduction in plane-to-plane noise coupling.


유사한 부품 번호 - ADV7122_15

제조업체부품명데이터시트상세설명
logo
Analog Devices
ADV7122KP30 AD-ADV7122KP30 Datasheet
196Kb / 12P
   CMOS 80 MHz, Triple 10-Bit Video DACs
REV. B
ADV7122KP50 AD-ADV7122KP50 Datasheet
196Kb / 12P
   CMOS 80 MHz, Triple 10-Bit Video DACs
REV. B
ADV7122KP80 AD-ADV7122KP80 Datasheet
196Kb / 12P
   CMOS 80 MHz, Triple 10-Bit Video DACs
REV. B
ADV7122KST30 AD-ADV7122KST30 Datasheet
196Kb / 12P
   CMOS 80 MHz, Triple 10-Bit Video DACs
REV. B
ADV7122KST50 AD-ADV7122KST50 Datasheet
196Kb / 12P
   CMOS 80 MHz, Triple 10-Bit Video DACs
REV. B
More results

유사한 설명 - ADV7122_15

제조업체부품명데이터시트상세설명
logo
Analog Devices
ADV7121 AD-ADV7121 Datasheet
196Kb / 12P
   CMOS 80 MHz, Triple 10-Bit Video DACs
REV. B
ADV7120KSTZ50 AD-ADV7120KSTZ50 Datasheet
191Kb / 12P
   CMOS 80 MHz, Triple 8-Bit Video DAC
REV. B
ADV7120 AD-ADV7120_15 Datasheet
191Kb / 12P
   CMOS 80 MHz, Triple 8-Bit Video DAC
REV. B
ADV101 AD-ADV101_15 Datasheet
161Kb / 12P
   CMOS 80 MHz, Triple 8-Bit Video DAC
REV. B
ADV101 AD-ADV101 Datasheet
187Kb / 12P
   CMOS 80 MHz, Triple 8-Bit Video DAC
REV. B
ADV7120KSTZ30 AD-ADV7120KSTZ30 Datasheet
191Kb / 12P
   CMOS 80 MHz, Triple 8-Bit Video DAC
REV. B
ADV7120 AD-ADV7120 Datasheet
188Kb / 12P
   CMOS 80 MHz, Triple 8-Bit Video DAC
REV. B
ADV7128 AD-ADV7128 Datasheet
135Kb / 8P
   CMOS 80 MHz, 10-Bit Video DAC
REV. 0
ADV7128 AD-ADV7128_15 Datasheet
139Kb / 8P
   CMOS 80 MHz, 10-Bit Video DAC
REV. 0
logo
Exar Corporation
CDK3400 EXAR-CDK3400 Datasheet
648Kb / 11P
   10-bit, 100/150MSPS, Triple Video DACs
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12


데이터시트 다운로드

Go To PDF Page


링크 URL




개인정보취급방침
ALLDATASHEET.CO.KR
ALLDATASHEET 가 귀하에 도움이 되셨나요?  [ DONATE ] 

Alldatasheet는?   |   광고문의   |   운영자에게 연락하기   |   개인정보취급방침   |   링크교환   |   제조사별 검색
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com