Why does the LTC2485 datasheet say to use a tantalum Vcc bypass capacitor?

Question

Page 10 indicates that the Vcc should be bypassed with a 0.1uF and 1 uF caps. It says that the 1 uF should be Tantalum. Why is this? 
 
 www.analog.com/.../2485fd.pdf

Yugel · Accepted Answer

Hello adamvs , 
 Tantalums are preferred because the internal LDO needs to have a high-ESR capacitor to ensure stability across operating conditions. Well, this is not strictly tantalum, you can add in place a ceramic capacitor with a series resistor of maybe 5-10 ohms. But then, that would be an extra component added to the BOM. 
 
 Regards, 
 Yugel)

JCCillion · Answer

Hi Aless , 
 You may use the evaluation board schematic and BOM as a guide in designing your own board. While the tantalum capacitor is preferred for the reason Yugel mentioned, it is not mandatory. 
 Hope this helps. 
 Regards, 
 JC

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Why does the LTC2485 datasheet say to use a tantalum Vcc bypass capacitor?