In this paper, a new regenerative switching device with a graded AlxGa1-xAs/InGaAs/GaAs heterostructure has been fabricated and demonstrated. A thin p(+)-InGaAs quantum well (QW) is employed between n-GaAs and p(+)-GaAs layers to provide a significant confinement effect for electrons. An interesting S-shaped multiple negative differential resistance (NDR) phenomenon and three operation points are observed, due to an avalanche multiplication and sequential two-stage barrier lowering effect resulting from the successive accumulation of holes and electrons at the p(+)-GaAs base regime and InGaAs quantum well respectively. Consequently, with appropriate adjustments of device parameters, the proposed heterostructure provides a good promise for multiple-valued logic circuit applications.