A current sensing device (1) for producing a voltage indicative of an alternating current flowing in a conductor (2) comprises a support element (5) within which a carrier element (11) is located. The carrier element (11) comprises a primary substrate (12) which is formed into a multi-channel arcuate configuration defining a plurality of longitudinally extending channels (13) with side walls (16) on which planar coils (17) are formed on respective opposite first and second major surfaces (14,15) of the primary substrate (12). The carrier element (11) is located and retained in the multi-channel arcuate configuration in a primary retaining recess (38) in the support element (5) with the planar coils (17) defining planes which extend radially from a main central axis (6) defined by the support element (5). The planar coils (17) are connected in series so that the voltages produced in the coils by the alternating current flowing in the conductor (2) are summed in phase and the sum of the respective voltages is produced across terminals (20,21) of a first output port (19). Capacitive plates of a capacitor may also be formed on the first and second major surfaces (14,15) of the primary substrate (12) or on a separate substrate in order to produce a signal indicative of the alternating voltage in the conductor (2).