LM25118 datasheet中举例设计计算是否有漏洞？

 在LM25118文档中，举例设计，条件如下：

Application Information
The procedure for calculating the external components is illustrated with the following design example. The
designations used in the design example correlate to the final schematic shown in Figure 25. The design
specifications are:
• VOUT = 12V
• VIN = 4V to 42V
• F = 300 kHz
• Minimum load current (CCM operation) = 600 mA
• Maximum load current = 3A

但在实际计算中还是沿用了LM5118中的设计信息

Application Information
The procedure for calculating the external components is illustrated
with the following design example. The designations
used in the design example correlate to the final schematic
shown in Figure 18. The design specifications are:
• VOUT = 12V
• VIN = 5V to 75V
• F = 300 kHz
• Minimum load current (CCM operation) = 600 mA
• Maximum load current = 3A

所以得出的计算值

The resulting inductor values are:
• L1 = 28 μH, Buck Mode
• L1 = 9.8 μH Buck-Boost mode有误！

是否这是文档上的一个漏洞？

Johnsin Tao：

Hi 

    如你所说，两者的输入条件不同，但是计算结果完全一样，是不对的。

    原因是两者其实主要的差别在于输出电压范围上的变化，因此计算方法可以沿用， 而LM5118中因为沿用了这个计算方法，而忽略了输入电压的改变。

    建议你重点参考datasheet中提供的计算方法。