參數(shù)資料
型號: LM3477
廠商: National Semiconductor Corporation
英文描述: High Efficiency High-Side N-Channel Controller for Switching Regulator
中文描述: 高效率高側(cè)N溝道開關(guān)穩(wěn)壓器控制器
文件頁數(shù): 10/23頁
文件大?。?/td> 815K
代理商: LM3477
Functional Block Diagram
20003301
Functional Description
General Description
The LM3477/A is a switching regulator controller for topolo-
gies incorporating a high side switch. The most common of
these topologies is the step-down, or buck, converter. Other
topologies such as the inverting (buck-boost) and inverse
SEPIC (zeta) converters can be realized. This datasheet will
focus on buck converter applications.
The LM3477/A employs current mode control architecture.
Among the many benefits of this architecture are superior
line and load regulation, cycle-by-cycle current limiting, and
simple loop compensation. The LM3477/A features a pat-
ented adjustable slope compensation scheme to enable flex-
ible inductor selection. The LM3477/A has a combination of
features that allow its use in a wide variety of applications.
The input voltage can range from 2.97V to 35V, with the
output voltage being positive or negative depending on the
topology. The current limit can be scaled to safely drive a
wide range of loads. An internal soft-start is provided to limit
initial in-rush current. Output over voltage and input under
voltage protection ensure safe operation of the LM3477/A.
Regions of Operation
Pulse width modulation (PWM) is the normal mode of opera-
tion. In PWM, the output voltage is well regulated and has a
ripple frequency equal to the switching frequency (500kHz).
In low load conditions, the part operates in hysteretic mode.
In this mode, the output voltage is regulated between a high
and low value that results in a higher ripple magnitude and
lower ripple frequency than in PWM mode (see
OVER VOLT-
AGE PROTECTION
section).
200033J2
FIGURE 1. Operating Regions of the LM3477/A
L
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相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LM3477A 制造商:NSC 制造商全稱:National Semiconductor 功能描述:High Efficiency High-Side N-Channel Controller for Switching Regulator
LM3477AMM 功能描述:DC/DC 開關(guān)控制器 RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
LM3477AMM/NOPB 功能描述:DC/DC 開關(guān)控制器 RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
LM3477AMMX 功能描述:DC/DC 開關(guān)控制器 RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
LM3477AMMX/NOPB 功能描述:DC/DC 開關(guān)控制器 RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK