TI中文支持网TI's LM5155 chip is used in a certain project. We expect the output voltage to be 11V, with a load of 10A and a duration of 100ms.In the actual test, it was found that the output voltage would drop to 8.64V when the output voltage was about 6.5A. Please help to review the attached schematic diagram for how to improve Boost's load capacity. What we expect is that when the output current reaches 10A or higher, the output voltage can be dropped within 100ms but the minimum voltage will not fall below 9.5V.
We suspect that it may be caused by the following reasons:
1) The output cannot be stabilized due to inductance saturation
2) Output loop is unstable due to compensation network
3) the diode we have chosen before may not pass 5A. After replacing the diode with a diode that can carry a current of 30A, there is only a small improvement.
Johnsin Tao：
Hi带载能力下降建议检查如下：1.功率电感饱和电流是否足够？ 建议至少是最大输出峰值电流的1.3倍。2.功率回路尽量小。3.电流保护sense电阻layout上避免noise，以及合理RC滤波的合理设计。建议你在确认电感没有问题后，示波器确认CS脚信号？
Xu Qing：
回复 Johnsin Tao:
你好，已经确认电感的输出峰值电流远大于最大输出峰值电流的1.3倍。
下图一是使用三个串联法拉电容[3V，25F]进行供电，Vin=7V，负载为6A，CH1（黄色）：CS CH2（蓝色）：输出电压
在负载为6A时的波形，此时输出能在400ms内稳定在11V
Xu Qing：
回复 Johnsin Tao:
下图二（使用三个串联法拉电容[3V，25F]进行供电）
Vin=7V，负载为7A，CH1（黄色）：CS CH2（蓝色）：输出电压
在负载为7A时，在100ms内输出无法稳定在11V
Johnsin Tao：
回复 Xu Qing:
Hi2,3两点，确认没有？
