參數(shù)資料
型號: LM2453TA
廠商: NATIONAL SEMICONDUCTOR CORP
元件分類: 音頻/視頻放大
英文描述: Monolithic Triple 6 nS CRT Driver With Integrated Clamp and G1 Blanking
中文描述: 3 CHANNEL, AUDIO/VIDEO AMPLIFIER, PZFM15
封裝: PLASTIC, TO-220, 15 PIN
文件頁數(shù): 6/14頁
文件大?。?/td> 823K
代理商: LM2453TA
G1 DRIVER/BOOST Electrical Characteristic Targets and Limits
(See Figure 13 for
Test Circuit)
Unless otherwise noted: V
CC
= +80V, V
BB
= +8V, T
C
= 50C, V
REF
= 1.735V, HEATSINK MUST BE GROUNDED VIA LOW
HF IMPEDANCE.
Symbol
I
G1-H
V
G1-L
V
G1PP
V
G1TH
V
120BOOST
I
BOOST
Note 7:
Input from signal generator: V
HIGH
>
2 V
DC
, V
LOW
<
0.5 V
DC
; t
HIGH
= 300 μs, t
LOW
= 10 ms. Rise/fall time
<
0.1 μs.
Parameter
Conditions
Min
Typ
49
6
43
0.9
123
50
Max
Units
V
DC
V
DC
V
P-P
V
V
mA
Typical G1 High Output Voltage
Typical G1 Low Output Voltage
Typical G1 Output Swing
G1 Blanking Input Threshold
Typical 120V Boost Supply
Typical 120V Boost Charge Current
V
BLANK
Input Low, See (Note 7).
V
BLANK
Input Low, See (Note 7).
120V Boost/G1 Drive Test Circuit
Theory of Operation
The LM2453 is a high voltage monolithic three channel CRT
driver and three-channel DC clamp circuit suitable for high-
resolution display applications. The device also contains a
G1 blanking signal driver, which also can be used to gener-
ate a 120 VDC supply to power the DC clamp circuit. The
LM2453 operates using 80V and 8V power supplies. An ex-
ternal supply can also be used to power the clamp circuit if
the user desires to do so. The part is housed in the industry
standard 15-lead TO-220 molded plastic power package.
A simplified circuit block diagram of the LM2453 is shown in
Figure 1 A reference supply of approximately 1.7 VDC is
supplied to pin 9 of the device. This provides a reference
level for the minus input of the video and clamp buffer ampli-
fiers as well as for the vertical blank comparator. The output
of the buffer amplifier drives the video amplifier which pro-
vides a gain of -52 to the input signal and only amplifies the
portion of the input signal that is above the reference volt-
age. When the input signal is at or below V
the video out-
puts are driven to the +80V supply rail. The output of the
driver is a low impedance complimentary emitter follower cir-
cuit that minimizes the effect of capacitive load variations on
transient response.
The clamp amplifier provides a gain of 73 and only amplifies
the portion of the input signal that is below the reference volt-
age. When the input signal is at or above V
the clamp
outputs are driven to the V
/120V supply rail. The vertical
blank comparator drives the boost circuit, which generates a
40 V
signal that can directly drive typical G1 capacitive
loads. When the first vertical blanking pulse is received, the
G1 drive output enters a current limited latched state until the
120V boost capacitor is fully charged. Thereafter, the G1
output pulses in response to the vertical blanking pulse re-
ceived on the multiplexed V
REF
signal line.
Figures 4, 11, 13 show the typical test circuits for evaluation
of the LM2453.
Application Hints
INTRODUCTION
National Semiconductor (NSC) is committed to provide ap-
plication information that assists our customers in obtaining
the best performance possible from our products. The follow-
ing information is provided in order to support this commit-
ment. The reader should be aware that the optimization of
performance was done using a specific printed circuit board
designed at NSC. Variations in performance can be realized
due to physical changes in the printed circuit board and the
application. Therefore, the designer should know that com-
ponent value changes might be required in order to optimize
performance in a given application. The values shown in this
document can be used as a starting point for evaluation pur-
poses. When working with high bandwidth circuits, good lay-
out practices are always critical to achieving maximum per-
formance.
DS101302-13
FIGURE 13. 120V Boost/G1 Drive Test Circuit
L
www.national.com
6
相關(guān)PDF資料
PDF描述
LM2459 Monolithic Single Channel 15 MHz DTV CRT Driver
LM2459TE Monolithic Single Channel 15 MHz DTV CRT Driver
LM2463 Monolithic Triple 4 ns CRT Driver
LM2465 Monolithic Triple 5.5 ns High Gain CRT Driver
LM2466 Monolithic Triple 7.5 ns CRT Driver
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LM2457 制造商:未知廠家 制造商全稱:未知廠家 功能描述:
LM2459 制造商:NSC 制造商全稱:National Semiconductor 功能描述:Monolithic Single Channel 15 MHz DTV CRT Driver
LM2459C WAF 制造商:Texas Instruments 功能描述:
LM2459TE 制造商:NSC 制造商全稱:National Semiconductor 功能描述:Monolithic Single Channel 15 MHz DTV CRT Driver
LM246 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:PROGRAMMABLE QUAD BIPOLAR OPERATIONAL AMPLIFIERS