Although Lo-fi is in vogue these days, to consider Caroline Guitar's Somersault low fidelity is an injustice. It's pitch may waver, there may not be a sine wave in sight but this is all perfectly accomplished. Nothing sounds "broken" here or is reminiscent of an effect brought back by nostalgia.
It is a perfect vibrato. It can place you on a sonic wave in triangle mode or create a unique tremolo, one that actually changes pitch within a square wave.
While the digital chip sets the delayed wet signal, the initial gain stage, dry signal, LFO, control set and output mixing stage are entirely analog.