- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄44549 > LM2637MWC (NATIONAL SEMICONDUCTOR CORP) SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, UUC PDF資料下載
參數(shù)資料
| 型號： | LM2637MWC |
| 廠商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, UUC |
| 封裝： | WAFER |
| 文件頁數(shù)： | 4/20頁 |
| 文件大小： | 404K |
| 代理商： | LM2637MWC |
Applications Information (Continued)
That is, if f
z = 1.32 kHz, fp = 153 kHz, and A = 4.8x10
6
F,
then the cutoff frequency will be 50 kHz, the phase margin
will be 72, and the DC gain will be that of the error amplifier.
See
Figure 8.
The compensation network component values can be deter-
mined by
Equation (9), since the values of f
z,fp and A are
now known. To more conveniently calculate the values,
Equation (9) can be rearranged as follows:
(11)
Notice there are three equations but four variables. So one
of the variables can be chosen arbitrarily. Since the current
driving capability of the error amplifier is limited to around 3
mA, it is a good idea to have a high impedance path from
EAO to FB. From
Equation (11) it can be told that a larger R
2
will result in a smaller C
1,C2 and a larger R1. Calculations
show that the following combination is a good one: R
2 =
51
,C
1 = 0.022 f, R1 = 5.6 k,C2 = 820 pF.
For a different application or different type of output capaci-
tors, a different compensation scheme may be necessary.
The user can either follow the steps above to figure the ap-
propriate component values or contact National for help.
Linear Section — The linear section is designed for high con-
trol bandwidth operation. The phase margin and cutoff fre-
quency depends on the external N-FET, output capacitors
and their ESR. As a rule of thumb, the designer can choose
any capacitance from 50 F to 4000 F, with a total ESR of
10 m
to 100 m. The larger the capacitance, the lower the
bandwidth. The above capacitors usually result in a control
bandwidth of 250 kHz to 1.2 MHz.
DS100848-17
FIGURE 6. Buck Converter from a Control Viewpoint
DS100848-18
FIGURE 7. Control-to-Output Bode Plots
DS100848-19
FIGURE 8. Loop Bode Plots
www.national.com
12
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LM2639MX/NOPB | SWITCHING CONTROLLER, 8700 kHz SWITCHING FREQ-MAX, PDSO24 |
| LM2639M/NOPB | SWITCHING CONTROLLER, 8700 kHz SWITCHING FREQ-MAX, PDSO24 |
| LM2639MWC | SWITCHING CONTROLLER, 8700 kHz SWITCHING FREQ-MAX, UUC |
| LM2641-ADJMDC | DUAL SWITCHING CONTROLLER, 345 kHz SWITCHING FREQ-MAX, UUC |
| LM2645MTD/NOPB | SWITCHING CONTROLLER, 335 kHz SWITCHING FREQ-MAX, PDSO48 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LM2637MX/NOPB | 功能描述:IC MOTHERBRD PWR SUPPLY 24-SOIC RoHS:是 類別:集成電路 (IC) >> PMIC - 電源管理 - 專用 系列:- 應(yīng)用說明:Ultrasound Imaging Systems Application Note 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:37 系列:- 應(yīng)用:醫(yī)療用超聲波成像，聲納 電流 - 電源:- 電源電壓:2.37 V ~ 6 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:56-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:56-TQFN-EP（8x8） 包裝:管件 |
| LM2638 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述: |
| LM2638M | 制造商:Texas Instruments 功能描述: |
| LM2638M/NOPB | 功能描述:IC MOTHERBRD PWR SUPPLY 24-SOIC RoHS:是 類別:集成電路 (IC) >> PMIC - 電源管理 - 專用 系列:- 應(yīng)用說明:Ultrasound Imaging Systems Application Note 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:37 系列:- 應(yīng)用:醫(yī)療用超聲波成像，聲納 電流 - 電源:- 電源電壓:2.37 V ~ 6 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:56-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:56-TQFN-EP（8x8） 包裝:管件 |
| LM2638MX | 功能描述:IC MOTHERBRD PWR SUPPLY 24-SOIC RoHS:是 類別:集成電路 (IC) >> PMIC - 電源管理 - 專用 系列:- 應(yīng)用說明:Ultrasound Imaging Systems Application Note 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:37 系列:- 應(yīng)用:醫(yī)療用超聲波成像，聲納 電流 - 電源:- 電源電壓:2.37 V ~ 6 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:56-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:56-TQFN-EP（8x8） 包裝:管件 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。