參數(shù)資料
型號(hào)： LM2577TADJFLOWLB03
廠商： NATIONAL SEMICONDUCTOR CORP
元件分類： 穩(wěn)壓器
英文描述： 6 A SWITCHING REGULATOR, 62 kHz SWITCHING FREQ-MAX, PZFM5
封裝： PLASTIC, TO-220, 5 PIN
文件頁(yè)數(shù)： 13/27頁(yè)
文件大?。?/td> 889K
代理商： LM2577TADJFLOWLB03
Application Hints (Continued)
C.
Calculate the minimum value of CC
D.
Calculate the maximum ESR of the +V
OUT and VOUT
output capacitors in parallel.
This formula can also be used to calculate the maximum
ESR of a single output regulator.
At this point, refer to this same section in the Step-Up Regu-
lator Design Procedurefor more information regarding the
selection of C
OUT.
3. Output Voltage Selection
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 voltage down so it can
be compared with the LM1577-ADJ/LM2577-ADJ internal
1.23V reference. For a desired output voltage V
OUT, select
R1 and R2 so that
4. Diode Selection
The switching diode in a flyback converter must withstand
the reverse voltage specified by the following equation.
A suitable diode must have a reverse voltage rating greater
than this. In addition it must be rated for more than the aver-
age and peak diode currents listed in
Figure 19.
5. Input Capacitor Selection
The primary of a flyback transformer draws discontinuous
pulses of current from the input supply. As a result, a flyback
regulator generates more noise at the input supply than a
step-up regulator, and this requires a larger bypass capacitor
to decouple the LM1577/LM2577 V
IN pin from this noise. For
most applications, a low ESR, 1.0 F cap will be sufficient, if
it is connected very close to the V
IN and Ground pins.
Duty Cycle
D
Primary Current Variation
I
P
Peak Primary Current
I
P(PK)
Switch Voltage when Off
V
SW(OFF)
Diode Reverse Voltage
V
R
V
OUT
+ N(V
IN
V
SAT)
Average Diode Current
I
D(AVE)
I
LOAD
Peak Diode Current
I
D(PK)
Short Circuit Diode Current
Power Dissipation of
LM1577/LM2577
P
D
DS011468-78
FIGURE 19. Flyback Regulator Formulas
www.national.com
20
相關(guān)PDF資料
PDF描述
LM2578MWC 0.75 A SWITCHING REGULATOR, 100 kHz SWITCHING FREQ-MAX, UUC
LM2586-5.0MDC 7 A SWITCHING REGULATOR, 200 kHz SWITCHING FREQ-MAX, UUC
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
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LM2577T-ADJFLOWLB03 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Current-Mode SMPS Controller
LM2578AM 功能描述:直流/直流開(kāi)關(guān)轉(zhuǎn)換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開(kāi)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
LM2578AM/NOPB 功能描述:直流/直流開(kāi)關(guān)轉(zhuǎn)換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開(kāi)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
LM2578AM/NOPB 制造商:Texas Instruments 功能描述:DC/DC Converter IC
LM2578AMX 功能描述:直流/直流開(kāi)關(guān)轉(zhuǎn)換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開(kāi)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(xiě)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

*
*
*