Would like to know what is this symbol and its function

Good day community, can I know what is this symbol could be? It looks like a ramp/ continuous ramp. But I believe it is not both them. I saw someone connect it after a voltage/ current measurement. Can I know what is the function of this symbol too? Much appreciate for the answers given

[Kilsu Kim]

It looks like "Saturation" block but the direction of the block is opposite.

[Ying Jie Tan]

I've think about this before, but if Im not mistaken, the saturation block came with the y and x axis too right? Or we can hide that axes to become like the block I've attached above?