- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄358822 > LM2587S-3.3 (NATIONAL SEMICONDUCTOR CORP) RP DPA 60 DUST CAP PDF資料下載
參數(shù)資料
| 型號(hào)： | LM2587S-3.3 |
| 廠商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | RP DPA 60 DUST CAP |
| 中文描述： | 5 A SWITCHING REGULATOR, 100 kHz SWITCHING FREQ-MAX, PSSO5 |
| 封裝： | TO-263, 5 PIN |
| 文件頁數(shù)： | 10/26頁 |
| 文件大?。?/td> | 676K |
| 代理商： | LM2587S-3.3 |
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頁當(dāng)前第10頁第11頁第12頁第13頁第14頁第15頁第16頁第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
Flyback Regulator Operation
The LM2587 is ideally suited for use in the flyback regulator
topology. The flyback regulator can produce a single output
voltage, such as the one shown in Figure 4 or multiple out-
put voltages. In Figure 4 the flyback regulator generates an
output voltage that is inside the range of the input voltage.
This feature is unique to flyback regulators and cannot be
duplicated with buck or boost regulators.
The operation of a flyback regulator is as follows (refer to
Figure 4): when the switch is on, current flows through the
primary winding of the transformer, T1, storing energy in the
magnetic field of the transformer. Note that the primary and
secondary windings are out of phase, so no current flows
through the secondary when current flows through the pri-
mary. When the switch turns off, the magnetic field col-
lapses, reversing the voltage polarity of the primary and sec-
ondary windings. Now rectifier D1 is forward biased and
current flows through it, releasing the energy stored in the
transformer. This produces voltage at the output.
The output voltage is controlled by modulating the peak
switch current. This is done by feeding back a portion of the
output voltage to the error amp, which amplifies the differ-
ence between the feedback voltage and a 1.230V reference.
The error amp output voltage is compared to a ramp voltage
proportional to the switch current (i.e., inductor current dur-
ing the switch on time). The comparator terminates the
switch on time when the two voltages are equal, thereby
controlling the peak switch current to maintain a constant
output voltage.
Typical Performance Characteristics
DS012316-10
As shown in Figure 4 the LM2587 can be used as a flyback regulator by using a minimum number of external components. The switching waveforms of this
FIGURE 4. 12V Flyback Regulator Design Example
DS012316-11
A: Switch Voltage, 10 V/div
AC-Coupled
Horizontal: 2 μs/div
FIGURE 5. Switching Waveforms
www.national.com
10
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LM2587S-12 | CONNECTOR |
| LM2587SX-ADJ | SIMPLE SWITCHER 5A Flyback Regulator |
| LM2587SX-3.3 | SIMPLE SWITCHER 5A Flyback Regulator |
| LM2587SX-12 | SIMPLE SWITCHER 5A Flyback Regulator |
| LM2587 | Octal D-type Edge-Triggered Flip-Flops With 3-State Outputs 20-TSSOP -40 to 85 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LM2587S5.0 | 制造商:National Semiconductor 功能描述:Conv DC-DC Single Step Up 4V to 40V 6-Pin(5+Tab) TO-263 Rail |
| LM2587S-5.0 | 功能描述:直流/直流開關(guān)轉(zhuǎn)換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關(guān)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(fēng)格:SMD/SMT |
| LM2587S-5.0/NOPB | 功能描述:直流/直流開關(guān)轉(zhuǎn)換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關(guān)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(fēng)格:SMD/SMT |
| LM2587S50 | 制造商:Texas Instruments 功能描述:SWITCHING REG 5A 5.0V SMD 2587 |
| LM2587S-ADJ | 功能描述:直流/直流開關(guān)轉(zhuǎn)換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關(guān)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(fēng)格:SMD/SMT |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。