欢迎访问ic37.com |
会员登录 免费注册
发布采购

VDP3130Y 参数 Datasheet PDF下载

VDP3130Y图片预览
型号: VDP3130Y
PDF下载: 下载PDF文件 查看货源
内容描述: 视频处理器家族 [Video Processor Family]
分类和应用:
文件页数/大小: 76 页 / 1707 K
品牌: MICRONAS [ MICRONAS ]
 浏览型号VDP3130Y的Datasheet PDF文件第19页浏览型号VDP3130Y的Datasheet PDF文件第20页浏览型号VDP3130Y的Datasheet PDF文件第21页浏览型号VDP3130Y的Datasheet PDF文件第22页浏览型号VDP3130Y的Datasheet PDF文件第24页浏览型号VDP3130Y的Datasheet PDF文件第25页浏览型号VDP3130Y的Datasheet PDF文件第26页浏览型号VDP3130Y的Datasheet PDF文件第27页  
ADVANCE INFORMATION  
VDP 313xY  
2.11.3.Average Beam Current Limiter  
2.11.4.Analog RGB Insertion  
The average beam current limiter (BCL) uses the  
sense input for the beam current measurement. The  
BCL uses a different filter to average the beam current  
during the active picture. The filter bandwidth is  
approx. 2 kHz. The beam current limiter has an auto-  
matic offset adjustment that is active two lines before  
the first cutoff measurement line.  
The VDP 313xY allows insertion of 2 external analog  
RGB signals. Each RGB signal is key-clamped and  
inserted into the main RGB by the fast blank switch.  
The selected external RGB input is virtually handled as  
a priority bus signal. Thus, it can be overlaid or under-  
laid to the digital picture. The external RGB signals can  
be adjusted independently as regards DC-level (bright-  
ness) and magnitude (contrast).  
The beam current limiter function is located in the  
front-end. The data exchange between the front-end  
and the back-end is done via a single-wire serial inter-  
face.  
Which analog RGB input is selected depends on the  
fast blank input signals and the programming of a num-  
ber of I2C-bus register settings (see Table 22 and Fig.  
221). Both fast blank inputs must be either active-low  
or active-high.  
The beam current limiter allows the setting of a thresh-  
old current. If the beam current is above the threshold,  
the excess current is lowpass filtered and used to  
attenuate the RGB outputs by adjusting the whitedrive  
multipliers for the internal (digital) RGB signals, and  
the analog contrast multipliers for the analog RGB  
inputs, respectively. The lower limit of the attenuator is  
programmable, thus a minimum contrast can always  
be set. During the tube measurement, the ABL attenu-  
ation is switched off. After the whitedrive measurement  
line it takes 3 lines to switch back to BCL limited drives  
and brightness.  
All signals for analog RGB insertion (RIN1/2, GIN1/2,  
BIN1/2, FBLIN1/2, HCS) must be synchronized to the  
horizontal flyback, otherwise a horizontal jitter will be  
visible. The VDP 313xY has no means for timing cor-  
rection of the analog RGB input signals.  
Table 22: RGB Input Selection  
FBFOH1=0, FBFOH2=0, FBFOL1=0, FBFOL2=0  
Typical characteristics of the ABL for different loop  
gains are shown in Fig. 220; for this example the tube  
has been assumed to have square law characteristics.  
FBLIN1 FBLIN2 FBPOL FBPRIO  
RGB output  
Video  
0
0
1
1
1
0
0
0
1
1
0
1
0
1
1
0
0
1
0
1
0
0
0
0
0
1
1
1
1
1
x
x
x
0
1
0
1
x
x
x
RGB input 2  
RGB input 1  
RGB input 1  
RGB input 2  
RGB input 1  
RGB input 2  
RGB input 1  
RGB input 2  
Video  
Fig. 220: Beam current limiter characteristics:  
beam current output vs. drive  
BCL threshold: 1  
Micronas  
23