參數(shù)資料
型號(hào)： LM2585T-ADJ
廠商： NATIONAL SEMICONDUCTOR CORP
元件分類： 穩(wěn)壓器
英文描述： SIMPLE SWITCHER 3A Flyback Regulator
中文描述： 7 A SWITCHING REGULATOR, 125 kHz SWITCHING FREQ-MAX, PZFM5
封裝： BENT STAGGERED, TO-220, 5 PIN
文件頁(yè)數(shù)： 20/25頁(yè)
文件大小： 627K
代理商： LM2585T-ADJ
Application Hints
PROGRAMMING OUTPUT VOLTAGE
(SELECTING R
1
AND R
2
)
Referring to the adjustable regulator in Figure 38 the output
voltage is programmed by the resistors R
1
and R
2
by the fol-
lowing formula:
V
OUT
= V
REF
(1 + R
1
/R
2
)
Resistors R
and R
divide the output voltage down so that
it can be compared with the 1.23V internal reference. With
R
2
between 1k and 5k, R
1
is:
R
1
= R
2
(V
OUT
/V
REF
1)
For best temperature coefficient and stability with time, use
1% metal film resistors.
where V
REF
= 1.23V
where V
REF
= 1.23V
SHORT CIRCUIT CONDITION
Due to the inherent nature of boost regulators, when the out-
put is shorted (see Figure 38), current flows directly from the
input, through the inductor and the diode, to the output, by-
passing the switch. The current limit of the switch does not
limit the output current for the entire circuit. To protect the
load and prevent damage to the switch, the current must be
externally limited, either by the input supply or at the output
with an external current limit circuit. The external limit should
be set to the maximum switch current of the device, which is
3A.
In a flyback regulator application (Figure 39), using the stan-
dard transformers, the LM2585 will survive a short circuit to
the main output. When the output voltage drops to 80% of its
nominal value, the frequency will drop to 25 kHz. With a
lower frequency, off times are larger. With the longer off
times, the transformer can release all of its stored energy be-
fore the switch turns back on. Hence, the switch turns on ini-
tially with zero current at its collector. In this condition, the
switch current limit will limit the peak current, saving the
device.
DS012515-55
FIGURE 38. Boost Regulator
DS012515-56
FIGURE 39. Flyback Regulator
www.national.com
20
相關(guān)PDF資料
PDF描述
LM2585S-ADJ SIMPLE SWITCHER 3A Flyback Regulator
LM2585 Octal D-type Edge-Triggered Flip-Flops With 3-State Outputs 20-PDIP -40 to 85
LM2586SX-5.0 SIMPLE SWITCHER 3A Flyback Regulator with Shutdown
LM2586S-12 Octal D-type Edge-Triggered Flip-Flops With 3-State Outputs 20-SO -40 to 85
LM2586S-3.3 Octal D-type Edge-Triggered Flip-Flops With 3-State Outputs 20-SO -40 to 85
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LM2585T-ADJ 制造商:Texas Instruments 功能描述:SWITCHING REG 3A 12V 2585 TO2205
LM2585T-ADJ/LB03 制造商:Texas Instruments 功能描述:Conv DC-DC Single Step Up 4V to 40V 5-Pin(5+Tab) TO-220 Rail
LM2585T-ADJ/LB04 制造商:Texas Instruments 功能描述:Conv DC-DC Single Step Up 4V to 40V 5-Pin(5+Tab) TO-220 Rail
LM2585T-ADJ/NOPB 功能描述:直流/直流開(kāi)關(guān)轉(zhuǎn)換器 3-AMP FLYBACK REG 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
LM2586S-12 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

*
*
*