- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄385474 > LM1212N (NATIONAL SEMICONDUCTOR CORP) 230 MHz Video Amplifier System with OSD Blanking PDF資料下載
參數(shù)資料
| 型號： | LM1212N |
| 廠商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分類： | 音頻／視頻放大 |
| 英文描述： | 230 MHz Video Amplifier System with OSD Blanking |
| 中文描述： | 1 CHANNEL, VIDEO AMPLIFIER, PDIP20 |
| 封裝： | N20A |
| 文件頁數(shù)： | 13/18頁 |
| 文件大?。?/td> | 300K |
| 代理商： | LM1212N |
Applications of the LM1212
SINGLE VIDEO CHANNEL
A typical application for a single video channel is shown in
Figure 9. The video signal is AC coupled to pin 6. The
LM1212 internally biases the video signal to 2.6 V
DC
. Con-
trast control is achieved by applying a 0V to 4V DC voltage
at pin 8. The amplifier’s gain is minimum (i.e., maximum sig-
nal attenuation) if pin 8 is at 0V and is maximum if pin 8 is at
4V. With pin 9 (drive control) at 0V, the amplifier has a maxi-
mum gain of 10.
For DC restoration, a clamp signal must be applied to the
clamp gate input (pin 14). The clamp signal should be logic
low (less than 0.8V) only during the back porch (black level
reference period) interval (see Figure 2 ). The clamp gate
input is TTL compatible. Brightness control is provided by
applying a 0V to 4V DC voltage at pin 19. For example, if pin
19 is biased at 1V then the video signal’s black level will be
clamped at 1V. A 510
X
load resistor is connected from the
video output pin (pin 17) to ground. This resistor biases the
output stage of the amplifier. For power dissipation consid-
erations, the load resistor should not be much less than
510
X
.
RGB VIDEO PREAMPLIFIER
Figure 10 shows an RGB video preamplifier circuit using
three LM1212s. Note that pin 2 of IC1 is connected to pin 2
of IC2 and IC3 respectively. This allows IC1 to provide a
master contrast control and optimum contrast tracking.
Connecting pin 1 of all 3 ICs together provides the refer-
ence voltage for the contrast control. Adjusting the contrast
voltage at pin 8 of IC1 will vary the gain of all three video
channels. Drive control input (pin 9) of each LM1212 allows
individual gain adjustment for achieving white balance.
The black level of each video channel can be individually
adjusted to the desired voltage by adjusting the voltage at
pin 19. In a DC-coupled cathode drive application, adjusting
the voltage at pin 19 of each IC will provide cutoff adjust-
ment. In an AC-coupled cathode drive application, the video
signal is AC coupled and DC restored at the cathode. In
such an application, the video signal’s black level may be
clamped to the desired level by simply biasing pin 19 to the
black level voltage by using a voltage divider at pin 19.
http://www.national.com
13
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LM1229 | I2C Compatible CMOS TV RGB and Deflection Processor |
| LM1229VEC | I2C Compatible CMOS TV RGB and Deflection Processor |
| LM1229YA | I2C Compatible CMOS TV RGB and Deflection Processor |
| LM1247 | 150 MHz I2C Compatible RGB Preamplifier with Internal 512 Character OSD ROM, 512 Character RAM and 4 DACs |
| LM1270 | Hi-Brite 200 MHz I2C Compatible RGB Image Enhancer with Video Auto Sizing |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LM121AH/883 | 制造商:NSC 制造商全稱:National Semiconductor 功能描述:LM221/LM321 Precision Preamplifiers |
| LM121H WAF | 制造商:Texas Instruments 功能描述: |
| LM121H/883 | 制造商:NSC 制造商全稱:National Semiconductor 功能描述:LM221/LM321 Precision Preamplifiers |
| LM121-S | 功能描述:基本/快動開關(guān) Foot Switch RoHS:否 制造商:Omron Electronics 觸點(diǎn)形式:SPDT 執(zhí)行器:Lever 電流額定值:5 A 電壓額定值 AC:250 V 電壓額定值 DC:30 V 功率額定值: 工作力:120 g IP 等級:IP 67 NEMA 額定值: 端接類型:Wire 安裝:Panel |
| LM122 | 制造商:NSC 制造商全稱:National Semiconductor 功能描述:Precision Timers |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。