• 回复
  • 收藏
  • 点赞
  • 分享
  • 发新帖

用UC3842的电源,空载MOS管温升略高,如何降低功率管温升?

一款用UC3842的开关电源,12V 2A、5V2A(USB外置盒用)空载时MOS功率管温升略高,有点烫手,而我用过别的UC3842电源功率管几乎无温升,如何降低功率管温升呢?
全部回复(8)
正序查看
倒序查看
keenfeng
LV.4
2
2005-01-13 12:51
how many degree?
0
回复
陈芳
LV.4
3
2005-01-13 12:54
@keenfeng
howmanydegree?
空载大概在40度左右
0
回复
jxmlhy
LV.4
4
2005-02-10 21:53
@陈芳
空载大概在40度左右
40度会烫手???
  我的都到80多了
0
回复
hjjk
LV.6
5
2005-02-12 18:16
MOS管的波形是不是正常的?如正常,加大散热片吧,呵呵呵
0
回复
陈芳
LV.4
6
2005-02-12 23:25
@hjjk
MOS管的波形是不是正常的?如正常,加大散热片吧,呵呵呵
另一款电路几乎一样的电源,空载时MOS却很凉…
0
回复
cleu39
LV.1
7
2005-02-12 23:43
You can operate with a lower switching frequency with no load condition.  It will reduce the switching loss.  Someone has done in this way.
Check the lower MOSFET temparature module, find out the timing R and C subcircuit in its control circuit.  Please post it if you have some results.
0
回复
蓝海
LV.5
8
2005-02-20 04:17
输入高压时,空载损耗有多少?
测试一下降3842的PIN4脚波形是否正常?
0
回复
polestar
LV.5
9
2005-02-20 08:35
@陈芳
另一款电路几乎一样的电源,空载时MOS却很凉…
有一家電源:芯片3842+外圍電路能使整機空載時降低開關頻率來降低
空載損耗.
0
回复