The problem is likely to be because electrolytic caps have high relative ESR compared to ceramics.

At the bottom of page 8 of the [data sheet][1] it says: -

> All capacitors must maintain a low (<100m Ω) equivalent series
> resistance (ESR)

Such small values as typically used are not always found in electrolytic types.

  [1]: http://datasheets.maximintegrated.com/en/ds/MAX682-MAX684.pdf