  This work is a short communication where phase function method has been
applied to obtain the phase shifts using Effective Range Approximation
potential for $^3S_1-np$, $^1S_0-nn$, $^1S_0-np$, and $^1S_0-pp$ states. No
free fitting parameters are used in calculations and reasonably good match with
the experimental phase shifts is observed for E $\leq$ 20 MeV. Potentials are
obtained for n-n, n-p, and p-p scattering that are exponential well-shaped.
