- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄377971 > ML4861 (Fairchild Semiconductor Corporation) Low Voltage Drop Boost Regulator(低壓差升壓穩(wěn)壓器) PDF資料下載
參數(shù)資料
| 型號： | ML4861 |
| 廠商： | Fairchild Semiconductor Corporation |
| 英文描述： | Low Voltage Drop Boost Regulator(低壓差升壓穩(wěn)壓器) |
| 中文描述： | 低壓降升壓穩(wěn)壓器（低壓差升壓穩(wěn)壓器） |
| 文件頁數(shù)： | 6/11頁 |
| 文件大?。?/td> | 118K |
| 代理商： | ML4861 |
ML4861
6
REV. 1.0 10/12/2000
100
1.0
3.0
I
O
2.0
200
300
400
500
0
L = 10μH
L = 15μH
L = 27μH
L = 56μH
V
IN
(V)
ML4861-3.3
100
1.0
3.0
4.0
I
O
2.0
200
300
400
500
0
L = 10μH
L = 15μH
L = 27μH
L = 56μH
ML4861-5.0
V
IN
(V)
100
1.0
3.0
4.0
I
O
2.0
200
300
400
500
0
L = 10μH
L = 15μH
L = 27μH
L = 56μH
ML4861-6.0
V
IN
(V)
5.0
6.0
Figure 5 shows efficiency under the conditions used to
create Figure 4. It can be seen that efficiency is mostly
independent of input voltage and is closely related to
inductor value. This illustrates the need to keep the
inductor value as high as possible to attain peak system
efficiency. As the inductor value goes down to 10μH, the
efficiency drops to between 70% and 75%. With 56μH,
the efficiency exceeds 90% and there is little room for
improvement. At values greater than 100μH, the
operation of the synchronous rectifier becomes unreliable
because the inductor current is so small that it is difficult
for the control circuitry to detect. The data used to
generate Figures 4 and 5 is provided in Table 1.
After the appropriate inductor value is chosen, it is
necessary to find the minimum inductor current rating
required. Peak inductor current is determined from the
following formula:
I
T
V
L
L PEAK
(
ON MAX
(
IN MAX
(
MIN
)
)
)
=
×
(3)
In the two cell application previously described, a
maximum input voltage of 3V would give a peak current
of 1.2A. When comparing various inductors, it is
important to keep in mind that suppliers use different
criteria to determine their ratings. Many use a
conservative current level, where inductance has dropped
to 90% of its normal level. In any case, it is a good idea
to try inductors of various current ratings with the ML4861
to determine which inductor is the best choice. Check
efficiency and maximum output current, and if a current
probe is available, look at the inductor current to see if it
looks like the waveform shown in Figure 3. For additional
information, see Applications Note 29, “Choosing an
Inductor for Your ML4861 Application.”
Suitable inductors can be purchased from the following
suppliers:
Coilcraft
(708) 639-6400
Coiltronics
(407) 241-7876
Dale
(605) 665-9301
Sumida
(708) 956-0666
Figure 4. Output Current vs Input Voltage.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| ML4863 | High Efficiency Flyback Controller(高效回轉(zhuǎn)電源控制器) |
| ML4865CS-2 | High Voltage High Current Boost Regulator |
| ML4865 | High Voltage High Current Boost Regulator |
| ML4866 | 3.3V Output DC-DC Step-Down Converter(3.3V輸出的DC-DC步降變換器) |
| ML4869 | Medium Current Boost Regulator with Load Disconnect(負(fù)載可分離的中等電流升壓穩(wěn)壓器) |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| ML4861CS-3 | 制造商:MICRO-LINEAR 制造商全稱:MICRO-LINEAR 功能描述:Low Voltage Boost Regulator |
| ML4861CS-5 | 制造商:MICRO-LINEAR 制造商全稱:MICRO-LINEAR 功能描述:Low Voltage Boost Regulator |
| ML4861CS6 | 制造商:Rochester Electronics LLC 功能描述:- Bulk |
| ML4861CS-6 | 制造商:MICRO-LINEAR 制造商全稱:MICRO-LINEAR 功能描述:Low Voltage Boost Regulator |
| ML4861ES-3 | 制造商:MICRO-LINEAR 制造商全稱:MICRO-LINEAR 功能描述:Low Voltage Boost Regulator |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。