參數(shù)資料
型號(hào)： LM2586-5.0MDC
廠商： NATIONAL SEMICONDUCTOR CORP
元件分類： 穩(wěn)壓器
英文描述： 7 A SWITCHING REGULATOR, 200 kHz SWITCHING FREQ-MAX, UUC
封裝： DIE
文件頁(yè)數(shù)： 17/32頁(yè)
文件大?。?/td> 858K
代理商： LM2586-5.0MDC
Application Hints (Continued)
OUTPUT VOLTAGE LIMITATIONS
The maximum output voltage of a boost regulator is the
maximum switch voltage minus a diode drop. In a flyback
regulator, the maximum output voltage is determined by the
turns ratio, N, and the duty cycle, D, by the equation:
V
OUT ≈ NxVIN xD/(1D)
The duty cycle of a flyback regulator is determined by the fol-
lowing equation:
Theoretically, the maximum output voltage can be as large
as desired — just keep increasing the turns ratio of the trans-
former. However, there exists some physical limitations that
prevent the turns ratio, and thus the output voltage, from in-
creasing to infinity. The physical limitations are capacitances
and inductances in the LM2586 switch, the output diode(s),
and the transformer — such as reverse recovery time of the
output diode (mentioned above).
NOISY INPUT LINE CONDITION
A small, low-pass RC filter should be used at the input pin of
the LM2586 if the input voltage has an unusually large
amount of transient noise, such as with an input switch that
bounces. The circuit in
Figure 44 demonstrates the layout of
the filter, with the capacitor placed from the input pin to
ground and the resistor placed between the input supply and
the input pin. Note that the values of R
IN and CIN shown in
the schematic are good enough for most applications, but
some readjusting might be required for a particular applica-
tion. If efficiency is a major concern, replace the resistor with
a small inductor (say 10 H and rated at 200 mA).
STABILITY
All current-mode controlled regulators can suffer from an in-
stability, known as subharmonic oscillation, if they operate
with a duty cycle above 50%. To eliminate subharmonic os-
cillations, a minimum value of inductance is required to en-
sure stability for all boost and flyback regulators. The mini-
mum inductance is given by:
where V
SAT is the switch saturation voltage and can be
found in the Characteristic Curves.
DS012516-63
FIGURE 44. Input Line Filter
DS012516-64
FIGURE 45. Circuit Board Layout
www.national.com
24
相關(guān)PDF資料
PDF描述
LM2586-5.0MWC 7 A SWITCHING REGULATOR, 200 kHz SWITCHING FREQ-MAX, UUC
LM2586-ADJMDC 7 A SWITCHING REGULATOR, 200 kHz SWITCHING FREQ-MAX, UUC
LM2586SX-12/NOPB 3 A SWITCHING REGULATOR, 200 kHz SWITCHING FREQ-MAX, PSSO7
LM2587SX-3.3/NOPB 5 A SWITCHING REGULATOR, 100 kHz SWITCHING FREQ-MAX, PSSO5
LM2588-12MWC 9.5 A SWITCHING REGULATOR, 200 kHz SWITCHING FREQ-MAX, UUC
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LM2586S-12 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
LM2586S-12/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
LM2586S-3.3 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
LM2586S-3.3/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
LM2586S-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
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*