công cụ tìm kiếm bảng dữ liệu linh kiện điện tử
  Vietnamese  ▼
ALLDATASHEET.VN

X  

LM3578A bảng dữ liệu(PDF) 10 Page - National Semiconductor (TI)

[Old version datasheet] Texas Instruments acquired National semiconductor. Click here to check the latest version.
tên linh kiện LM3578A
Giải thích chi tiết về linh kiện  Switching Regulator
Download  20 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
nhà sản xuất  NSC [National Semiconductor (TI)]
Trang chủ  http://www.national.com
Logo NSC - National Semiconductor (TI)

LM3578A bảng dữ liệu(HTML) 10 Page - National Semiconductor (TI)

Back Button LM3578A Datasheet HTML 6Page - National Semiconductor (TI) LM3578A Datasheet HTML 7Page - National Semiconductor (TI) LM3578A Datasheet HTML 8Page - National Semiconductor (TI) LM3578A Datasheet HTML 9Page - National Semiconductor (TI) LM3578A Datasheet HTML 10Page - National Semiconductor (TI) LM3578A Datasheet HTML 11Page - National Semiconductor (TI) LM3578A Datasheet HTML 12Page - National Semiconductor (TI) LM3578A Datasheet HTML 13Page - National Semiconductor (TI) LM3578A Datasheet HTML 14Page - National Semiconductor (TI) Next Button
Zoom Inzoom in Zoom Outzoom out
 10 / 20 page
background image
Applications Information (Continued)
DUTY CYCLE ADJUSTMENT
When manual or mechanical selection of the output transis-
tor’s duty cycle is needed, the cirucit shown below may be
used. The output will turn on with the beginning of each
oscillator cycle and turn off when the current sunk by R2 and
R3 from the non-inverting terminal becomes greater than the
current sunk from the inverting terminal.
With the resistor values as shown, R3 can be used to adjust
the duty cycle from 0% to 90%.
When the sum of R2 and R3 is twice the value of R1, the
duty cycle will be about 50%. C1 may be a large electrolytic
capacitor to lower the oscillator frequency below 1 Hz.
REMOTE SHUTDOWN
The LM2578A may be remotely shutdown by sinking a
greater current from the non-inverting input than from the
inverting input. This may be accomplished by selecting re-
sistor R3 to be approximately one-half the value of R1 and
R2 in parallel.
EMITTER OUTPUT
When the LM2578A output transistor is in the OFF state, if
the Emitter output swings below the ground pin voltage, the
output transistor will turn ON because its base is clamped
near ground. The Collector Current with Emitter Output Be-
low Ground curve shows the amount of Collector current
drawn in this mode, vs temperature and Emitter voltage.
When the Collector-Emitter voltage is high, this current will
cause high power dissipation in the output transistor and
should be avoided.
This situation can occur in the high-current high-voltage
buck application if the Emitter output is used and the catch
diode’s forward voltage drop is greater than 0.6V. A fast-
recovery diode can be added in series with the Emitter
output to counter the forward voltage drop of the catch diode
(see Figure 2). For better efficiency of a high output current
buck regulator, an external PNP transistor should be used as
shown in Figure 16.
SYNCHRONIZING DEVICES
When several devices are to be operated at once, their
oscillators may be synchronized by the application of an
external signal. This drive signal should be a pulse waveform
with a minimum pulse width of 2 µs. and an amplitude from
00871121
FIGURE 9. Maximum Duty Cycle Limiting
00871123
FIGURE 10. Duty Cycle Adjustment
00871124
FIGURE 11. Shutdown Occurs when V
L is High
00871130
FIGURE 12. D1 Prevents Output Transistor from
Improperly Turning ON due to D2’s Forward Voltage
www.national.com
10


Số phần tương tự - LM3578A

nhà sản xuấttên linh kiệnbảng dữ liệuGiải thích chi tiết về linh kiện
logo
National Semiconductor ...
LM3578A NSC-LM3578A Datasheet
1Mb / 18P
   Switching Regulator
logo
Texas Instruments
LM3578A TI-LM3578A Datasheet
1Mb / 30P
[Old version datasheet]   LM2578A/LM3578A Switching Regulator
LM3578A TI1-LM3578A Datasheet
1Mb / 30P
[Old version datasheet]   Switching Regulator
logo
National Semiconductor ...
LM3578AM NSC-LM3578AM Datasheet
1Mb / 18P
   Switching Regulator
logo
Texas Instruments
LM3578AM TI-LM3578AM Datasheet
1Mb / 30P
[Old version datasheet]   LM2578A/LM3578A Switching Regulator
More results

Mô tả tương tự - LM3578A

nhà sản xuấttên linh kiệnbảng dữ liệuGiải thích chi tiết về linh kiện
logo
Toshiba Semiconductor
TPC8012-H TOSHIBA-TPC8012-H_06 Datasheet
270Kb / 7P
   Switching Regulator Applications Switching Regulator Applications
logo
Texas Instruments
PT7778-3.3V TI1-PT7778-3.3V Datasheet
183Kb / 4P
[Old version datasheet]   Switching Regulator
logo
National Semiconductor ...
LM1578A NSC-LM1578A Datasheet
1Mb / 18P
   Switching Regulator
logo
Sanyo Semicon Device
LA5757TP SANYO-LA5757TP Datasheet
78Kb / 6P
   Switching Regulator
LA5756 SANYO-LA5756 Datasheet
125Kb / 4P
   Switching Regulator
logo
ON Semiconductor
CS5111 ONSEMI-CS5111 Datasheet
112Kb / 16P
   Switching Regulator
January, 2001 ??Rev. 9
logo
National Semiconductor ...
LM2579 NSC-LM2579 Datasheet
540Kb / 13P
   SWITCHING REGULATOR
logo
Texas Instruments
LM2578A TI1-LM2578A Datasheet
1Mb / 30P
[Old version datasheet]   Switching Regulator
logo
ON Semiconductor
LA5774MC ONSEMI-LA5774MC Datasheet
313Kb / 6P
   Switching Regulator
May,2013
logo
XP Power Limited
STR XPPOWER-STR Datasheet
360Kb / 4P
   Switching Regulator
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20


bảng dữ liệu tải về

Go To PDF Page


Link URL




Chính sách bảo mật
ALLDATASHEET.VN
Cho đến nay ALLDATASHEET có giúp ích cho doanh nghiệp của bạn hay không?  [ DONATE ] 

Alldatasheet là   |   Quảng cáo   |   Liên lạc với chúng tôi   |   Chính sách bảo mật   |   Trao đổi link   |   Tìm kiếm theo nhà sản xuất
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com