參數(shù)資料
型號: LM2445
廠商: National Semiconductor Corporation
英文描述: Monolithic Triple 7.5 ns CRT Driver
中文描述: 單片三重7.5納秒CRT顯示器驅動
文件頁數(shù): 8/14頁
文件大小: 758K
代理商: LM2445
Application Hints
(Continued)
TABLE 1. LM2445 Cathode Response
Channel
Red
Green
Blue
t
r
/OS
6.3ns / 7%
6.1ns / 6%
6.5ns / 3%
t
f
/OS
6.3ns / 3%
5.9ns / 4%
6.4ns / 2%
PC BOARD LAYOUT CONSIDERATIONS
For optimum performance, an adequate ground plane, iso-
lation between channels, good supply bypassing and mini-
mizing unwanted feedback are necessary.Also, the length of
the signal traces from the preamplifier to the LM2445 and
from the LM2445 to the CRT cathode should be as short as
possible. The following references are recommended:
Ott, Henry W., “Noise Reduction Techniques in Electronic
Systems”, John Wiley & Sons, New York, 1976.
“Video Amplifier Design for Computer Monitors”, National
Semiconductor Application Note 1013.
Pease,
Robert
A.,
“Troubleshooting
Butterworth-Heinemann, 1991.
Analog
Circuits”,
Because of its high small signal bandwidth, the part may
oscillate in a monitor if feedback occurs around the video
channel through the chassis wiring. To prevent this, leads to
the video amplifier input circuit should be shielded, and input
circuit wiring should be spaced as far as possible from output
circuit wiring.
NSC DEMONSTRATION BOARD
Figure 13
shows the routing and component placement on
the NSC LM1267/2466 demonstration board. The schematic
of the board is shown in
Figure 11
and
Figure 12
. This board
provides a good example of a layout that can be used as a
guide for future layouts. Note the location of the following
components:
C19—V
bypass capacitor, located very close to pin 4
and ground pins
C20—V
BB
bypass capacitors, located close to pin 8 and
ground
C46, C47, C48—V
bypass capacitors, near LM2445
and V
CC
clamp diodes. Very important for arc protection.
The routing of the LM2445 outputs to the CRT is very critical
to achieving optimum performance.
Figure 14
shows the
routing and component placement from pin 1 of the LM2445
to the blue cathode. Note that the components are placed so
that they almost line up from the output pin of the LM2445 to
the blue cathode pin of the CRT connector. This is done to
minimize the length of the video path between these two
components. Note also that D8, D9, R24 and D6 are placed
to minimize the size of the video nodes that they are at-
tached to. This minimizes parasitic capacitance in the video
path and also enhances the effectiveness of the protection
diodes. The anode of protection diode D8 is connected
directly to a section of the the ground plane that has a short
and direct path to the LM2445 ground pins. The cathode of
D9 is connected to V
CC
very close to decoupling capacitor
C19 (see
Figure 14
) which is connected to the same section
of the ground plane as D8. The diode placement and routing
is very important for minimizing the voltage stress on the
LM2445 during an arcover event. Lastly, notice that S3 is
placed very close to the blue cathode and is tied directly to
CRT ground.
20063716
FIGURE 10. Red Cathode Response
L
www.national.com
8
相關PDF資料
PDF描述
LM2445TA Monolithic Triple 7.5 ns CRT Driver
LM2460 Monolithic Triple Channel High Swing CRT Driver
LM2460TA Monolithic Triple Channel High Swing CRT Driver
LM2462 Monolithic Triple 3 ns CRT Driver
LM2462TA Monolithic Triple 3 ns CRT Driver
相關代理商/技術參數(shù)
參數(shù)描述
LM2445TA 制造商:Texas Instruments 功能描述:CRT DRVR 85V 9-Pin(9+Tab) TO-220
LM2445TA/NOPB 功能描述:IC DRIVER CRT 3CH 7.5NS 9-TO-220 RoHS:是 類別:集成電路 (IC) >> PMIC - 顯示器驅動器 系列:- 產品培訓模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,500 系列:- 顯示器類型:真空熒光 (VF) 配置:5 x 7(矩陣) 接口:串行 數(shù)字或字符:- 電流 - 電源:3.5mA 電源電壓:2.7 V ~ 3.6 V 工作溫度:-40°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:16-SSOP(0.154",3.90mm 寬) 供應商設備封裝:16-QSOP 包裝:帶卷 (TR)
LM2450 制造商:NSC 制造商全稱:National Semiconductor 功能描述:220V Monolithic Triple Channel 7 MHz DC Coupled CRT DTV Driver
LM2451 制造商:NSC 制造商全稱:National Semiconductor 功能描述:220V Monolithic Triple Channel 12 MHz DC Coupled CRT DTV Driver
LM2451TB 制造商:Rochester Electronics LLC 功能描述: 制造商:Texas Instruments 功能描述: