- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄358821 > LM2577S-ADJ (NATIONAL SEMICONDUCTOR CORP) SIMPLE SWITCHER Step-Up Voltage Regulator PDF資料下載
參數(shù)資料
| 型號： | LM2577S-ADJ |
| 廠商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | SIMPLE SWITCHER Step-Up Voltage Regulator |
| 中文描述： | 6 A SWITCHING REGULATOR, 62 kHz SWITCHING FREQ-MAX, PSSO5 |
| 封裝： | TO-263, 5 PIN |
| 文件頁數(shù)： | 17/27頁 |
| 文件大?。?/td> | 889K |
| 代理商： | LM2577S-ADJ |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁當前第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁
Application Hints
(Continued)
3. Output Voltage Selection (R1 and R2)
This section is for applications using the LM1577-ADJ/
LM2577-ADJ. Skip this section if the LM1577-12/LM2577-12
or LM1577-15/LM2577-15 is being used.
With the LM1577-ADJ/LM2577-ADJ, the output voltage is
given by
V
OUT
= 1.23V (1 + R1/R2)
Resistors R1 and R2 divide the output down so it can be
compared
with
the
LM1577-ADJ/LM2577-ADJ
1.23V reference. For a given desired output voltage V
OUT
,
select R1 and R2 so that
internal
4. Input Capacitor Selection (C
IN
)
The switching action in the step-up regulator causes a trian-
gular ripple current to be drawn from the supply source. This
in turn causes noise to appear on the supply voltage. For
proper operation of the LM1577, the input voltage should be
decoupled. Bypassing the Input Voltage pin directly to
ground with a good quality, low ESR, 0.1 μF capacitor (leads
as short as possible) is normally sufficient.
If the LM1577 is located far from the supply source filter ca-
pacitors, an additional large electrolytic capacitor (e.g.
47 μF) is often required.
5. Diode Selection (D)
The switching diode used in the boost regulator must with-
stand a reverse voltage equal to the circuit output voltage,
and must conduct the peak output current of the LM2577. A
suitable diode must have a minimum reverse breakdown
voltage greater than the circuit output voltage, and should be
rated for average and peak current greater than I
and I
. Schottky barrier diodes are often favored for use
in switching regulators. Their low forward voltage drop allows
higher regulator efficiency than if a (less expensive) fast re-
covery diode was used. See Figure 12 for recommended
part numbers and voltage ratings of 1A and 3A diodes.
BOOST REGULATOR CIRCUIT EXAMPLE
By adding a few external components (as shown in Figure
13), the LM2577 can be used to produce a regulated output
voltage that is greater than the applied input voltage. Typical
performance of this regulator is shown in Figure 14 and Fig-
ure 15 The switching waveforms observed during the opera-
tion of this circuit are shown in Figure 16
Cornell Dublier
— Types 239, 250, 251, UFT,
300, or 350
P.O. Box 128, Pickens, SC 29671
(803) 878-6311
Nichicon
— Types PF, PX, or PZ
927 East Parkway,
Schaumburg, IL 60173
(708) 843-7500
Sprague
— Types 672D, 673D, or 674D
Box 1, Sprague Road,
Lansing, NC 28643
(919) 384-2551
United Chemi-Con
— Types LX, SXF, or SXJ
9801 West Higgins Road,
Rosemont, IL 60018
(708) 696-2000
FIGURE 11. Aluminum Electrolytic Capacitors
Recommended for Switching Regulators
V
OUT
(max)
20V
Schottky
Fast Recovery
1A
1A
3A
3A
1N5817
MBR120P
1N5818
MBR130P
11DQ03
1N5819
MBR140P
11DQ04
MBR150
11DQ05
1N5820
MBR320P
1N5821
MBR330P
31DQ03
1N5822
MBR340P
31DQ04
MBR350
31DQ05
30V
40V
1N4933
MUR105
1N4934
HER102
MUR110
10DL1
50V
MR851
30DL1
MR831
HER302
100V
FIGURE 12. Diode Selection Chart
www.national.com
17
相關PDF資料 |
PDF描述 |
|---|---|
| LM2577S-15 | SIMPLE SWITCHER Step-Up Voltage Regulator |
| LM2577M-15 | Pressure Transducer, Series 19 mm, Compensated, Pressure Range: 0 psi to 50 psi, Gage, 1/4-18 NPT, 10 Vdc excitation |
| LM2577M-12 | Pressure Transducer, Series 19 mm, Compensated, Pressure Range: 0 psi to 50 psi, Gage, 1/8-27 NPT, 10 Vdc excitation |
| LM2585SX-12 | SIMPLE SWITCHER 3A Flyback Regulator |
| LM2585SX-3.3 | SIMPLE SWITCHER 3A Flyback Regulator |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| LM2577S-ADJ/NOPB | 功能描述:直流/直流開關轉換器 STEP-UP VLTG REG RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數(shù)量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT |
| LM2577S-ADJ/NOPB | 制造商:Texas Instruments 功能描述:DC/DC Converter (DC-DC) / Switching Regu |
| LM2577SX-12 | 功能描述:直流/直流開關轉換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數(shù)量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT |
| LM2577SX-12/NOPB | 功能描述:直流/直流開關轉換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數(shù)量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT |
| LM2577SX-15 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Current-Mode SMPS Controller |
發(fā)布緊急采購，3分鐘左右您將得到回復。