A monolithic integrated proximity sensor device, comprising: - at least a first transmitter coil and a first receiver coil electrically insulated from one another; wherein - the proximity sensor device comprises a single semiconductor die comprising a semiconductor substrate with an active surface, and an interconnection stack on top of the active surface; - the single semiconductor die comprises at least one component selected from the group consisting of: an active component, a passive component, and a bond pad; - the interconnection stack comprises a plurality of at least two metal layers (M1, M2, M3, M4) separated by isolation layers; - the at least a first transmitter coil and the first receiver coil are implemented in the interconnection stack; - the first transmitter coil having a first spiral course with at least three turns formed in a first subset of at least one metal layer (M2,M3,M4; M2,M3,M4) selected from said plurality of metal layers, and wherein an orthogonal projection of the first spiral course on the active surface has a first inner periphery and a first outer periphery; and - the first receiver coil having a second spiral course with at least three turns formed in a second subset of at least one metal layer (M3,M4; M2,M3,M4) selected from said plurality of metal layers, and wherein an orthogonal projection of the second spiral course on the active surface has a second inner periphery and a second outer periphery; and - an orthogonal projection of said at least one component or bond pad on the active surface is located inside the first inner periphery and inside the second inner periphery, or is located inside the first inner periphery but outside of the second outer periphery. - at least a first transmitter coil and a first receiver coil electrically insulated from one another; wherein - the proximity sensor device comprises a single semiconductor die comprising a semiconductor substrate with an active surface, and an interconnection stack on top of the active surface; - the single semiconductor die comprises at least one component selected from the group consisting of: an active component, a passive component, and a bond pad; - the interconnection stack comprises a plurality of at least two metal layers (M1, M2, M3, M4) separated by isolation layers; - the at least a first transmitter coil and the first receiver coil are implemented in the interconnection stack; - the first transmitter coil having a first spiral course with at least three turns formed in a first subset of at least one metal layer (M2,M3,M4; M2,M3,M4) selected from said plurality of metal layers, and wherein an orthogonal projection of the first spiral course on the active surface has a first inner periphery and a first outer periphery; and - the first receiver coil having a second spiral course with at least three turns formed in a second subset of at least one metal layer (M3,M4; M2,M3,M4) selected from said plurality of metal layers, and wherein an orthogonal projection of the second spiral course on the active surface has a second inner periphery and a second outer periphery; and - an orthogonal projection of said at least one component or bond pad on the active surface is located inside the first inner periphery and inside the second inner periphery, or is located inside the first inner periphery but outside of the second outer periphery.