A trimming structure for trimming functional parameters of an Integrated Circuit - IC - comprising a first and at least one second functional blocks (115b,..., 115n) with which a first (Vrg,a) and at least one second IC voltages (Vrg,b..., Vrg,n) are respectively associated, said trimming structure comprising: respective trimmable circuit structures (205a, 210va,..., 205n, 210n) included in the first and at least one second functional blocks, a bandgap reference voltage generator in the IC to generate and feed bandgap voltages (Vbg) to the first and the at least one second function blocks as reference voltages, and trimming configuration storage means for storing trimming configuration values for the trimmable circuit structures, each trimming configuration value expressing a trimming configuration for the associated IC voltages in such a way that the first IC voltages depends on a first trimming confguration value through a first relationship and the at least one second IC voltage depends on at least one second trimming configuration value through an at least one second relationship, characterized in that the trimming configuration storage means are adapted to cause: when a change in the first trimming configuration value is made, the at least one second trimming configuration value is subjected to a change related to the change of the first trimming configuration value according to a prescribed relationship, so that: a change in the at least one second IC voltage in response to the corresponding change in the trimming configuration for the trimmable structure of the at least one second functional block is function of the change in the first IC voltage consequent to the change in the trimming configuration for the trimmable circuit structure of the first functional block. respective trimmable circuit structures (205a, 210va,..., 205n, 210n) included in the first and at least one second functional blocks, a bandgap reference voltage generator in the IC to generate and feed bandgap voltages (Vbg) to the first and the at least one second function blocks as reference voltages, and trimming configuration storage means for storing trimming configuration values for the trimmable circuit structures, each trimming configuration value expressing a trimming configuration for the associated IC voltages in such a way that the first IC voltages depends on a first trimming confguration value through a first relationship and the at least one second IC voltage depends on at least one second trimming configuration value through an at least one second relationship, characterized in that the trimming configuration storage means are adapted to cause: when a change in the first trimming configuration value is made, the at least one second trimming configuration value is subjected to a change related to the change of the first trimming configuration value according to a prescribed relationship, so that: a change in the at least one second IC voltage in response to the corresponding change in the trimming configuration for the trimmable structure of the at least one second functional block is function of the change in the first IC voltage consequent to the change in the trimming configuration for the trimmable circuit structure of the first functional block. when a change in the first trimming configuration value is made, the at least one second trimming configuration value is subjected to a change related to the change of the first trimming configuration value according to a prescribed relationship, so that: a change in the at least one second IC voltage in response to the corresponding change in the trimming configuration for the trimmable structure of the at least one second functional block is function of the change in the first IC voltage consequent to the change in the trimming configuration for the trimmable circuit structure of the first functional block.