- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄374721 > SC2441A (Semtech Corporation) 1.8V to 20V Input 2-Phase Synchronous Step-down Controllers with Step-up Converter PDF資料下載
參數(shù)資料
| 型號： | SC2441A |
| 廠商： | Semtech Corporation |
| 英文描述： | 1.8V to 20V Input 2-Phase Synchronous Step-down Controllers with Step-up Converter |
| 中文描述： | 1.8V至20V的輸入2相同步降壓與升壓轉換器控制器 |
| 文件頁數(shù)： | 35/37頁 |
| 文件大?。?/td> | 1024K |
| 代理商： | SC2441A |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁當前第35頁第36頁第37頁
35
2006 Semtech Corp.
www.semtech.com
POWER MANAGEMENT
Applications Information
SC2441A
Figure 25. Bode plots of the loop response.
The resulting crossover frequency is about 49.2kHz with
phase margin 90
o
.
If the circuit noise makes the converter jitter, a larger
C
3
than the calculated value can be used. Effectively the
converter bandwidth is reduced to reject high frequency
noises. The final circuit should be checked for stability
under load transients at different line voltages. The load
transient also needs to be measured to ensure that the
output voltage is within the specification window.
PC Board Layout Issues
Circuit board layout is very important for the proper
operation of high frequency switching power converters.
A power ground plane is required to reduce ground
bounces. The followings are suggested for proper layout.
Power Stage
1) Separate the power ground from the signal ground. In
SC2441A the power ground PGND1 should be tied to
the source terminal of lower MOSFETs. The signal ground
AGND should be tied to the negative terminal of the
output capacitor (output return terminal).
2) Minimize the size of pulse current loop. Place the top
MOSFET, the bottom MOSFET and the input capacitors
close to each other with short and wide traces. In addition
to the aluminum energy storage capacitors, add multi-
layer ceramic (MLC) capacitors from the input to the power
ground to improve high frequency bypass.
3) Reduce high frequency voltage ringing. Widen and
shorten the drain and source traces of the MOSFETs to
reduce stray inductances. Add a small RC snubber if
necessary to reduce the high frequency ringing at the
phase node. Sometimes slowing down the gate drive
signal also helps in reducing the high frequency ringing at
the phase node.
4) Shorten the gate driver path. Integrity of the gate drive
(voltage level, leading and falling edges) is important for
circuit operation and efficiency. Short and wide gate drive
traces reduce trace inductances. Bond wire inductance
is about 2~3nH. If the length of the PCB trace from the
gate driver to the MOSFET gate is 1 inch, the trace
inductance will be about 25nH. If the gate drive current
is 2A with 10ns rise and falling times, the voltage drops
across the bond wire and the PCB trace will be 0.6V and
5V respectively. This may slow down the switching
transient of the MOSFETs. These inductances may also
ring with the gate capacitance.
5) Put the decoupling capacitor for the gate drive power
supplies (BST and VCC) close to the IC and power ground.
10
10
100
1 10
3
1 10
4
1 10
5
1 10
6
3 10
5
50
0
50
100
73.323
17.588
20 log Gvcf ) C f )
f
f
10
10
100
1 10
3
1 10
4
1 10
5
1 10
6
3 10
5
96
94
92
90
90.001
94.713
arg Gvcf ) C f )
180
f
相關PDF資料 |
PDF描述 |
|---|---|
| SC2441AEVB | 1.8V to 20V Input 2-Phase Synchronous Step-down Controllers with Step-up Converter |
| SC2441ATETRT | 1.8V to 20V Input 2-Phase Synchronous Step-down Controllers with Step-up Converter |
| SC2441 | Very Low Input Voltage 2-Phase Synchronous Step-down Controllers with Step-up Converter |
| SC2441EVB | Very Low Input Voltage 2-Phase Synchronous Step-down Controllers with Step-up Converter |
| SC2441ITSTRT | Very Low Input Voltage 2-Phase Synchronous Step-down Controllers with Step-up Converter |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| SC2441A_09 | 制造商:SEMTECH 制造商全稱:Semtech Corporation 功能描述:1.8V to 20V Input 2-Phase Synchronous Step-down Controllers with Step-up Converter |
| SC2441AEVB | 制造商:SEMTECH 制造商全稱:Semtech Corporation 功能描述:1.8V to 20V Input 2-Phase Synchronous Step-down Controllers with Step-up Converter |
| SC2441ATETRT | 制造商:Semtech Corporation 功能描述: |
| SC2441EVB | 制造商:SEMTECH 制造商全稱:Semtech Corporation 功能描述:Very Low Input Voltage 2-Phase Synchronous Step-down Controllers with Step-up Converter |
| SC2441ITSTRT | 制造商:Semtech Corporation 功能描述:Controller IC |
發(fā)布緊急采購，3分鐘左右您將得到回復。