参数资料
| 型号： | ADV7120KPZ30 |
| 厂商： | Analog Devices Inc |
| 文件页数： | 11/12页 |
| 文件大小： | 0K |
| 描述： | IC DAC VIDEO 3CH 30MHZ 44PLCC |
| 产品培训模块： | Data Converter Fundamentals DAC Architectures |
| 标准包装： | 1 |
| 设置时间： | 12ns |
| 位数： | 8 |
| 数据接口： | 并联 |
| 转换器数目： | 3 |
| 电压电源： | 单电源 |
| 功率耗散（最大）： | 625mW |
| 工作温度： | 0°C ~ 70°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 44-LCC（J 形引线） |
| 供应商设备封装： | 44-PLCC（16.59x16.59） |
| 包装： | 管件 |
| 输出数目和类型： | 3 电流，单极 |
| 采样率（每秒）： | 30M |
ADV7120
REV. B
–8–
A resistance RSET connected between FS ADJUST and GND
determines the amplitude of the output video level according to
the following equations:
IOG (mA) = 12,082
× V
REF (V)/RSET (
)
(1)
IOR, IOB (mA) = 8,628
× V
REF (V)/RSET ()
(2)
If SYNC is not being encoded onto the green channel, then
Equation 1 will be similar to Equation 2.
Using a variable value of RSET, as shown in Figure 4, allows for
accurate adjustment of the analog output video levels. Use of a
fixed 560
R
SET resistor yields the analog output levels as
quoted in the specification page. These values also correspond
to the RS-343A video waveform values as shown in Figure 3.
TO DACs
ADV7120*
V
AA
V
REF
GND
1k
FS ADJUST
R
SET
560
500
100
*ADDITIONAL CIRCUITRY, INCLUDING
DECOUPLING COMPONENTS,
EXCLUDED FOR CLARITY
ANALOG POWER PLANE
COMP
0.1
F
5V
+
AD589
(1.235V
VOLTAGE
REFERENCE)
I
REF ≈ 4mA
Figure 4. Reference Circuit
D/A Converters
The ADV7120 contains three matched 8-bit D/A converters.
The DACs are designed using an advanced, high speed, seg-
mented architecture. The bit currents corresponding to each
digital input are routed to either the analog output (bit = “1”)
or GND (bit = “0”) by a sophisticated decoding scheme. As all
this circuitry is on one monolithic device, matching between the
three DACs is optimized. As well as matching, the use of identi-
cal current sources in a monolithic design guarantees monoto-
nicity and low glitch. The onboard operational amplifier
stabilizes the full-scale output current against temperature and
power supply variations.
Analog Outputs
The ADV7120 has three analog outputs, corresponding to the red,
green and blue video signals. A fourth analog output (ISYNC) can be
used if it is required to encode video synchronization information
onto the green signal. In this case, ISYNC is connected to IOG .
(See “Video Synchronization and Control” section.)
The red, green and blue analog outputs of the ADV7102 are
high impedance current sources. Each one of these three RGB
current outputs is capable of directly driving a 37.5
load, such
as a doubly terminated 75
coaxial cable. Figure 5a shows the
required configuration for each of the three RGB outputs con-
nected into a doubly terminated 75
load. This arrangement
will develop RS-343A video output voltage levels across a 75
monitor.
TERMINATION REPEATED THREE TIMES
FOR RED, GREEN AND BLUE DACs
DACs
IOR, IOG, IOB
(CABLE)
Z
O = 75
Z
S = 75
(SOURCE
TERMINATION)
Z
L = 75
(MONITOR)
Figure 5a. Analog Output Termination for RS-343A
One suggested method of driving RS-170 video levels into a 75
monitor is shown in Figure 5b. The output current levels of the
DACs remain unchanged but the source termination resistance,
ZS, on each of the three DACs is increased from 75
to 150 .
TERMINATION REPEATED THREE TIMES
FOR RED, GREEN AND BLUE DACs
DACs
IOR, IOG, IOB
(CABLE)
Z
O = 75
Z
S = 150
(SOURCE
TERMINATION)
Z
L = 75
(MONITOR)
Figure 5b. Analog Output Termination for RS-170
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 & Re-
quired Load Terminations” available from Analog Devices,
publication number E1228-15-1/89.
Figure 3 shows the video waveforms associated with the three
RGB outputs driving the doubly terminated 75
load of Figure
5a. As well as the gray scale levels, black level to white level, the
diagram also shows the contributions of SYNC and BLANK.
These control inputs add appropriately weighted currents to the
analog outputs, producing the specific output level requirements
for video applications. Table I details how the SYNC and
BLANK
inputs modify the output levels.
Gray Scale Operation
The ADV7120 can be used for stand-alone, gray scale (mono-
chrome) 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.
相关PDF资料 |
PDF描述 |
|---|---|
| ADV7125WBCPZ170 | IC DAC VIDEO 3-CH 330MHZ 48VFQFN |
| ADV7171KSZ-REEL | IC DAC VIDEO ENC NTSC 44-MQFP |
| ADV7172KSTZ-REEL | IC DAC VIDEO NTSC 6-CH 48-LQFP |
| ADV7177KSZ-REEL | IC DAC VIDEO NTSC 3-CH 44MQFP |
| ADV7179KCPZ-REEL | IC ENCODER VID NTSC/PAL 40LFCSP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| ADV7120KPZ50 | 功能描述:IC DAC VIDEO 3CH 50MHZ 44PLCC RoHS:是 类别:集成电路 (IC) >> 数据采集 - 数模转换器 系列:- 标准包装:2,400 系列:- 设置时间:- 位数:18 数据接口:串行 转换器数目:3 电压电源:模拟和数字 功率耗散（最大）:- 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:36-TFBGA 供应商设备封装:36-TFBGA 包装:带卷 (TR) 输出数目和类型:* 采样率（每秒）:* |
| ADV7120KPZ80 | 功能描述:IC DAC VIDEO 3CH 80MHZ 44PLCC RoHS:是 类别:集成电路 (IC) >> 数据采集 - 数模转换器 系列:- 标准包装:2,400 系列:- 设置时间:- 位数:18 数据接口:串行 转换器数目:3 电压电源:模拟和数字 功率耗散（最大）:- 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:36-TFBGA 供应商设备封装:36-TFBGA 包装:带卷 (TR) 输出数目和类型:* 采样率（每秒）:* |
| ADV7120KST30 | 制造商:Analog Devices 功能描述:DAC 3-CH Segment 8-bit 48-Pin LQFP 制造商:Rochester Electronics LLC 功能描述:TRIPLE 8 BIT VIDEO DAC I.C. - Bulk 制造商:Analog Devices 功能描述:IC ((NS)) |
| ADV7120KST30-REEL | 制造商:Analog Devices 功能描述:DAC 3-CH Segment 8-bit 48-Pin LQFP T/R 制造商:Rochester Electronics LLC 功能描述:TRIPLE 8 BIT VIDEO DAC I.C. - Tape and Reel |
| ADV7120KST50 | 制造商:Analog Devices 功能描述:DAC 3-CH Segment 8-bit 48-Pin TQFP 制造商:Rochester Electronics LLC 功能描述:TRIPLE 8 BIT VIDEO DAC I.C. - Bulk 制造商:Analog Devices 功能描述:IC 8-BIT VIDEO DAC |
发布紧急采购，3分钟左右您将得到回复。