  We introduce a new approach to the study of finite-dimensional
representations of the quantum group of the affine Lie superalgebra
$\mathrm{L}\mathfrak{gl}_{M|N}=\mathbb{C}[t,t^{-1}]\otimes\mathfrak{gl}_{M|N}$
($M\neq N$). We explain how the representations of the quantum group of
$\mathrm{L}\mathfrak{gl}_{M|N}$ are directly related to those of the quantum
affine algebra of type $A$, using an exact monoidal functor called truncation.
This can be viewed as an affine analogue of super duality of type $A$.
