- 您現(xiàn)在的位置：買(mǎi)賣(mài)IC網(wǎng) > PDF目錄385481 > LM3477MMX (NATIONAL SEMICONDUCTOR CORP) High Efficiency High-Side N-Channel Controller for Switching Regulator PDF資料下載
參數(shù)資料
| 型號(hào)： | LM3477MMX |
| 廠商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分類(lèi)： | 穩(wěn)壓器 |
| 英文描述： | High Efficiency High-Side N-Channel Controller for Switching Regulator |
| 中文描述： | 1 A SWITCHING CONTROLLER, 575 kHz SWITCHING FREQ-MAX, PDSO8 |
| 封裝： | MSOP-8 |
| 文件頁(yè)數(shù)： | 20/23頁(yè) |
| 文件大?。?/td> | 815K |
| 代理商： | LM3477MMX |
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)第14頁(yè)第15頁(yè)第16頁(yè)第17頁(yè)第18頁(yè)第19頁(yè)當(dāng)前第20頁(yè)第21頁(yè)第22頁(yè)第23頁(yè)
Compensation
(Continued)
The strategy taken here for choosing R
c
and C
C1
is to set the
crossover frequency with R
c
, and set the compensator zero
with C
C1
. Using the selected target crossover frequency, f
C
,
set R
C
to:
f
= Crossover frequency in Hertz (20kHz - 50kHz is recom-
mended)
R
GM
= 50x10
3
GM = 1000x10
6
A/V
The compensator zero, f
, is set with C
. When fast tran-
sient responses are desired, f
should be placed as high as
possible, however it should not be higher than the selected
crossover frequency f
. The guideline proposed here is to
choose C
such that f
falls somewhere between the
power pole f
P1
and
1
2
decade before the selected crossover
frequency fc:
In this compensation scheme, the pole created by C
is
used to cancel out the zero created by the ESR of the output
capacitor. In other schemes such as the methods discussed
in the
SAMPLING POLE QUALITY FACTOR
subsection, the
ESR zero is used. For the typical case, use C
C2
if:
Plotting the Open Loop Response
The open loop response is expressed as:
T = A
DC
x A
CM
x H x F
p
(s) x F
c
(s)
Where A
DC
and H are given above and
A
CM
= GM x R
GM
One can plot the magnitude and phase of the open loop
response to analyze the frequency response.
Example: Compensation Design
4.5V
≤
V
IN
≤
5.5V
V
OUT
= 2.5V
I
OUT
= 3A (R = 0.83
)
R
SN
= 0.02
L = 3.3μH
R
SL
= 0
C
OUT
= 100μF
R
ESR
= 0.01
First, calculate the power stage parameters using V
IN(MIN)
and R
(MAX)
:
In this example, a crossover frequency of 20kHz is chosen,
so: f
= 20000. R
is now calculated using the power stage
information and the target crossover frequency f
C
:
This sets the high frequency gain of the compensator such
that a crossover frequency of f
is obtained. The capacitor
C
sets the compensator zero, f
. Set f
between the
power pole f
and the
1
2
decade before the target cross-
over frequency f
C
:
L
www.national.com
20
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LM3478 | High Efficiency Low-Side N-Channel Controller for Switching Regulator |
| LM3478MM | High Efficiency Low-Side N-Channel Controller for Switching Regulator |
| LM3478MMX | High Efficiency Low-Side N-Channel Controller for Switching Regulator |
| LM3485 | Hysteretic PFET Buck Controller |
| LM3485MM | Hysteretic PFET Buck Controller |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LM3477MMX/NOPB | 功能描述:DC/DC 開(kāi)關(guān)控制器 RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開(kāi)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 |
| LM3478 | 制造商:NSC 制造商全稱(chēng):National Semiconductor 功能描述:High Efficiency Low-Side N-Channel Controller for Switching Regulator |
| LM3478_09 | 制造商:NSC 制造商全稱(chēng):National Semiconductor 功能描述:High Efficiency Low-Side N-Channel Controller for Switching Regulator |
| LM3478EVAL | 功能描述:BOARD EVALUATION LM3478 RoHS:否 類(lèi)別:編程器，開(kāi)發(fā)系統(tǒng) >> 評(píng)估板 - DC/DC 與 AC/DC（離線）SMPS 系列:- 產(chǎn)品培訓(xùn)模塊:Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:1 系列:True Shutdown™ 主要目的:DC/DC，步升 輸出及類(lèi)型:1，非隔離 功率 - 輸出:- 輸出電壓:- 電流 - 輸出:1A 輸入電壓:2.5 V ~ 5.5 V 穩(wěn)壓器拓?fù)浣Y(jié)構(gòu):升壓 頻率 - 開(kāi)關(guān):3MHz 板類(lèi)型:完全填充 已供物品:板 已用 IC / 零件:MAX8969 |
| LM3478EVAL/NOPB | 功能描述:電源管理IC開(kāi)發(fā)工具 EVAL BOARDFOR LM3478 RoHS:否 制造商:Maxim Integrated 產(chǎn)品:Evaluation Kits 類(lèi)型:Battery Management 工具用于評(píng)估:MAX17710GB 輸入電壓: 輸出電壓:1.8 V |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。