A biopsy driver assembly configured to mount a biopsy probe assembly, comprising: a biopsy driver housing; an electrical assembly (36, 700) coupled to said biopsy driver housing, said electrical assembly including at least one electrical drive (361, 362, 363) configured for drivably engaging said biopsy probe assembly; and a control circuit coupled to said biopsy driver housing, said control circuit being electrically coupled to said electrical assembly (36, 700), the biopsy driver assembly being characterized by: said control circuit having a motion detector, a timer circuit and a power dwell circuit: said power dwell circuit having a power output electrically connected to said electrical assembly (36, 700) and each of said motion detector and said timer circuit being electrically connected to receive electrical power from said power dwell circuit; said motion detector being communicatively coupled to said timer circuit and to said power dwell circuit, said motion detector being configured to provide a first signal to said power dwell circuit to cause said power dwell circuit to enter an operative mode wherein electrical power is supplied to said electrical assembly (36, 700) when said physical movement of said biopsy driver assembly is detected, and said motion detector being configured to provide a second signal to said timer circuit that indicates said last detected physical movement of said biopsy driver assembly; and said timer circuit being communicatively coupled to said power dwell circuit, said timer circuit being configured to provide a third signal to said power dwell circuit to cause said power dwell circuit to enter a power dwell mode wherein electrical power is supplied to said motion detector to the exclusion of said timer circuit and said electrical assembly, said third signal being supplied to said power dwell circuit after said predetermined time following said last detected physical movement of said biopsy driver assembly. a biopsy driver housing; an electrical assembly (36, 700) coupled to said biopsy driver housing, said electrical assembly including at least one electrical drive (361, 362, 363) configured for drivably engaging said biopsy probe assembly; and a control circuit coupled to said biopsy driver housing, said control circuit being electrically coupled to said electrical assembly (36, 700), the biopsy driver assembly being characterized by: said control circuit having a motion detector, a timer circuit and a power dwell circuit: said power dwell circuit having a power output electrically connected to said electrical assembly (36, 700) and each of said motion detector and said timer circuit being electrically connected to receive electrical power from said power dwell circuit; said motion detector being communicatively coupled to said timer circuit and to said power dwell circuit, said motion detector being configured to provide a first signal to said power dwell circuit to cause said power dwell circuit to enter an operative mode wherein electrical power is supplied to said electrical assembly (36, 700) when said physical movement of said biopsy driver assembly is detected, and said motion detector being configured to provide a second signal to said timer circuit that indicates said last detected physical movement of said biopsy driver assembly; and said timer circuit being communicatively coupled to said power dwell circuit, said timer circuit being configured to provide a third signal to said power dwell circuit to cause said power dwell circuit to enter a power dwell mode wherein electrical power is supplied to said motion detector to the exclusion of said timer circuit and said electrical assembly, said third signal being supplied to said power dwell circuit after said predetermined time following said last detected physical movement of said biopsy driver assembly. said power dwell circuit having a power output electrically connected to said electrical assembly (36, 700) and each of said motion detector and said timer circuit being electrically connected to receive electrical power from said power dwell circuit; said motion detector being communicatively coupled to said timer circuit and to said power dwell circuit, said motion detector being configured to provide a first signal to said power dwell circuit to cause said power dwell circuit to enter an operative mode wherein electrical power is supplied to said electrical assembly (36, 700) when said physical movement of said biopsy driver assembly is detected, and said motion detector being configured to provide a second signal to said timer circuit that indicates said last detected physical movement of said biopsy driver assembly; and said timer circuit being communicatively coupled to said power dwell circuit, said timer circuit being configured to provide a third signal to said power dwell circuit to cause said power dwell circuit to enter a power dwell mode wherein electrical power is supplied to said motion detector to the exclusion of said timer circuit and said electrical assembly, said third signal being supplied to said power dwell circuit after said predetermined time following said last detected physical movement of said biopsy driver assembly.