A circuit board in combination with a flow sensor , the flow sensor configured to be connected to a flow sensor base and having a plurality of piezo elements for transmitting a flow signal indicative of flow of a fluidic medicament, the circuit board comprising: a base having a first end and a second end, the base comprising a plurality of electrical circuit traces; a first pair of spring contacts for bias and electrical interface with a first piezo element , said first pair of spring contacts are mounted to said first end of said base and in electrical communication with at least one electrical circuit trace; a second pair of spring contacts for bias and electrical interface with a second piezo element , said second pair of spring contacts are mounted to said second end of said base and in electrical communication with at least one electrical circuit trace; and a plurality of pins in electrical contact with said plurality of electrical circuit traces, wherein said plurality of pins is configured to form electrical contacts with a plurality of contacts of the flow sensor base when said flow sensor is connected to said flow sensor base , characterized in that each of said spring contacts are pre-configured such that the bias against said first piezo element and the bias against said second piezo element are to be equal to each other in terms of nominal values of contact loads between the spring contacts and the piezo elements , with the first piezo element and the second piezo element in place for use, and each of said first pair of spring contacts and said second pair of spring contacts has a tolerance of a standoff larger than the standoff itself, and said electrical circuit traces are configured such that each of said pins is in electrical communication with a single spring contact . a base having a first end and a second end, the base comprising a plurality of electrical circuit traces; a first pair of spring contacts for bias and electrical interface with a first piezo element , said first pair of spring contacts are mounted to said first end of said base and in electrical communication with at least one electrical circuit trace; a second pair of spring contacts for bias and electrical interface with a second piezo element , said second pair of spring contacts are mounted to said second end of said base and in electrical communication with at least one electrical circuit trace; and a plurality of pins in electrical contact with said plurality of electrical circuit traces, wherein said plurality of pins is configured to form electrical contacts with a plurality of contacts of the flow sensor base when said flow sensor is connected to said flow sensor base , characterized in that each of said spring contacts are pre-configured such that the bias against said first piezo element and the bias against said second piezo element are to be equal to each other in terms of nominal values of contact loads between the spring contacts and the piezo elements , with the first piezo element and the second piezo element in place for use, and each of said first pair of spring contacts and said second pair of spring contacts has a tolerance of a standoff larger than the standoff itself, and said electrical circuit traces are configured such that each of said pins is in electrical communication with a single spring contact . <EOS>