參數(shù)資料
型號: LM2574N-15
廠商: NATIONAL SEMICONDUCTOR CORP
元件分類: 穩(wěn)壓器
英文描述: SIMPLE SWITCHER⑩ 0.5A Step-Down Voltage Regulator
中文描述: 1.8 A SWITCHING REGULATOR, 63 kHz SWITCHING FREQ-MAX, PDIP8
封裝: DIP-8
文件頁數(shù): 20/24頁
文件大?。?/td> 397K
代理商: LM2574N-15
LM2574
20
MOTOROLA ANALOG IC DEVICE DATA
R1
47 k
LM2574–XX
5
2
and
4
3
Gnds
Pins
ON/OFF
R2
47 k
+Vin
+Vin
C1
0.1
μ
F
Cin
22
μ
F
NOTE
: This picture does not show the complete circuit.
Figure 32. Delayed Startup Circuitry
Undervoltage Lockout
Some applications require the regulator to remain off until
the input voltage reaches a certain threshold level. Figure 33
shows an undervoltage lockout circuit applied to a buck
regulator. A version of this circuit for buck–boost converter is
shown in Figure 34. Resistor R3 pulls the ON/OFF pin high
and keeps the regulator off until the input voltage reaches a
predetermined threshold level, which is determined by the
following expression:
Vth
VZ1
1.0
R2
R1
10 k
Z1
1N5242B
R2
10 k
Q1
2N3904
R3
47 k
Cin
22
μ
F
LM2574–XX
5
2
and
4
3
Gnds
Pins
ON/OFF
+Vin
+Vin
NOTE
: This picture does not show the complete circuit.
Figure 33. Undervoltage Lockout Circuit for
Buck Converter
R2
15 k
Z1
1N5242
R1
15 k
Q1
2N3904
R3
68 k
Cin
22
μ
F
LM2574–XX
5
2
and
4
3
Gnds
Pins
ON/OFF
+Vin
+Vin
–Vout
NOTE
: This picture does not show the complete circuit (see Figure 27).
Figure 34. Undervoltage Lockout Circuit for
Buck–Boost Converter
Adjustable Output, Low–Ripple Power Supply
A 0.5 A output current capability power supply that
features an adjustable output voltage is shown in Figure 35.
This regulator delivers 0.5 A into 1.2 to 35 V output. The
input voltage ranges from roughly 3.0 to 40 V. In order to
achieve a 10 or more times reduction of output ripple, an
additional L–C filter is included in this circuit.
相關(guān)PDF資料
PDF描述
LM2574N-12 SIMPLE SWITCHER⑩ 0.5A Step-Down Voltage Regulator
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相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LM2574N-15/NOPB 功能描述:IC REG BUCK 15V 0.5A 8-DIP RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開關(guān)穩(wěn)壓器 系列:SIMPLE SWITCHER® 標(biāo)準(zhǔn)包裝:20 系列:SIMPLE SWITCHER® 類型:降壓(降壓) 輸出類型:固定 輸出數(shù):1 輸出電壓:12V 輸入電壓:4 V ~ 60 V PWM 型:電壓模式 頻率 - 開關(guān):52kHz 電流 - 輸出:1A 同步整流器:無 工作溫度:-40°C ~ 125°C 安裝類型:通孔 封裝/外殼:16-DIP(0.300",7.62mm) 包裝:管件 供應(yīng)商設(shè)備封裝:16-DIP 其它名稱:*LM2575HVN-12LM2575HVN-12
LM2574N-15G 制造商:ONSEMI 制造商全稱:ON Semiconductor 功能描述:0.5 A, Adjustable Output Voltage, Step−Down Switching Regulator
LM2574N-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
LM2574N-3.3 NOPB 制造商:National Semiconductor 功能描述:Conv DC-DC Single Step Down 4V to 40V 8-Pin PDIP Rail
LM2574N-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