參數(shù)資料
型號(hào)： LM2576-12
廠商： Motorola, Inc.
英文描述： Easy Switcher 3.0A Step-Down Voltage Regulator
中文描述： 輕松切換3.0A的降壓穩(wěn)壓器
文件頁(yè)數(shù)： 11/28頁(yè)
文件大?。?/td> 301K
代理商： LM2576-12
LM2576
11
MOTOROLA ANALOG IC DEVICE DATA
Procedure (Fixed Output Voltage Version) (continued)
In order to simplify the switching regulator design, a step–by–step
design procedure and some examples are provided.
Procedure
Example
5. Output Capacitor Selection (Cout)
A.
Since the LM2576 is a forward–mode switching regulator
with voltage mode control, its open loop 2–pole–1–zero
frequency characteristic has the dominant pole–pair
determined by the output capacitor and inductor values. For
stable operation and an acceptable ripple voltage,
(approximately 1% of the output voltage) a value between
680
μ
F and 2000
μ
F is recommended.
B.
Due to the fact that the higher voltage electrolytic capacitors
generally have lower ESR (Equivalent Series Resistance)
numbers, the output capacitor’s voltage rating should be at
least 1.5 times greater than the output voltage. For a 5.0 V
regulator, a rating at least 8.0 V is appropriate, and a 10 V or
16 V rating is recommended.
5. Output Capacitor Selection (Cout)
A.
Cout = 680
μ
F to 2000
μ
F standard aluminium electrolytic.
B.
Capacitor voltage rating = 20 V.
Procedure (Adjustable Output Version: LM2576–ADJ)
Procedure
Example
Given Parameters:
Vout = Regulated Output Voltage
Vin(max) = Maximum DC Input Voltage
ILoad(max) = Maximum Load Current
Given Parameters:
Vout = 8.0 V
Vin(max) = 25 V
ILoad(max) = 2.5 A
1. Programming Output Voltage
To select the right programming resistor R1 and R2 value (see
Figure 2) use the following formula:
Resistor R1 can be between 1.0 k and 5.0 k
. (For best
temperature coefficient and stability with time, use 1% metal
film resistors).
Vout
Vref
Vout
Vref
1.0
R2
R1
R2
R1
– 1.0
where Vref = 1.23 V
1. Programming Output Voltage
(selecting R1 and R2)
Select R1 and R2:
R2 = 9.91 k
, choose a 9.88 k metal film resistor.
R2
R1
Vout
Vref
1.0
1.8 k
8.0 V
1.23 V
1.0
Vout
1.23 1.0
R2
R1
Select R1 = 1.8 k
2. Input Capacitor Selection (Cin)
To prevent large voltage transients from appearing at the input
and for stable operation of the converter, an aluminium or
tantalum electrolytic bypass capacitor is needed between the
input pin +Vin and ground pin Gnd This capacitor should be
located close to the IC using short leads. This capacitor should
have a low ESR (Equivalent Series Resistance) value
.
For additional information see input capacitor section in the
“Application Hints” section of this data sheet.
2. Input Capacitor Selection (Cin)
A 100
μ
F, 150 V aluminium electrolytic capacitor located near
the input and ground pin provides sufficient bypassing.
3. Catch Diode Selection (D1)
A.
Since the diode maximum peak current exceeds the
regulator maximum load current the catch diode current
rating must be at least 1.2 times greater than the maximum
load current. For a robust design, the diode should have a
current rating equal to the maximum current limit of the
LM2576 to be able to withstand a continuous output short.
B.
The reverse voltage rating of the diode should be at least
1.25 times the maximum input voltage.
3. Catch Diode Selection (D1)
A.
For this example, a 3.0 A current rating is adequate.
B.
Use a 30 V 1N5821 Schottky diode or any
suggested fast recovery diode in the
Table 1.
相關(guān)PDF資料
PDF描述
LM2576-15 Easy Switcher 3.0A Step-Down Voltage Regulator
LM2576-3.3 Easy Switcher 3.0A Step-Down Voltage Regulator
LM2576-5 Easy Switcher 3.0A Step-Down Voltage Regulator
LM2576-ADJ Easy Switcher 3.0A Step-Down Voltage Regulator
LM2904V LinCMOS<TM> Precision Dual Operational Amplifier 8-PDIP -40 to 85
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LM2576-12BT 功能描述:IC REG BUCK 12V 3A TO220-5 RoHS:否 類(lèi)別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開(kāi)關(guān)穩(wěn)壓器 系列:- 標(biāo)準(zhǔn)包裝:20 系列:SIMPLE SWITCHER® 類(lèi)型:降壓（降壓） 輸出類(lèi)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(kāi)關(guān):52kHz 電流 - 輸出:1A 同步整流器:無(wú) 工作溫度:-40°C ~ 125°C 安裝類(lèi)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(chēng):*LM2575HVN-12LM2575HVN-12
LM2576-12BT⒂ 制造商:MICREL 制造商全稱(chēng):Micrel Semiconductor 功能描述:52kHz Simple 3A Buck Voltage Regulator
LM2576-12BU 功能描述:IC REG BUCK 12V 3A TO263-5 RoHS:否 類(lèi)別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開(kāi)關(guān)穩(wěn)壓器 系列:- 標(biāo)準(zhǔn)包裝:20 系列:SIMPLE SWITCHER® 類(lèi)型:降壓（降壓） 輸出類(lèi)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(kāi)關(guān):52kHz 電流 - 輸出:1A 同步整流器:無(wú) 工作溫度:-40°C ~ 125°C 安裝類(lèi)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(chēng):*LM2575HVN-12LM2575HVN-12
LM2576-12BU TR 功能描述:IC REG BUCK 12V 3A TO263-5 RoHS:否 類(lèi)別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開(kāi)關(guān)穩(wěn)壓器 系列:- 標(biāo)準(zhǔn)包裝:20 系列:SIMPLE SWITCHER® 類(lèi)型:降壓（降壓） 輸出類(lèi)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(kāi)關(guān):52kHz 電流 - 輸出:1A 同步整流器:無(wú) 工作溫度:-40°C ~ 125°C 安裝類(lèi)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(chēng):*LM2575HVN-12LM2575HVN-12
LM2576-12BUTR 制造商:Rochester Electronics LLC 功能描述:- Tape and Reel
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

*
*
*