The invention concerns a voltage-current converter having: a first current mirror containing two transistors that are designed such that under identical drive conditions the current flowing through the first transistor is greater than the current flowing through the second transistor by a predetermined factor. An inlet metering plate is disposed upstream of the battery packs to meter the uneven flow of cooling air generated by the inlet manifold. The first semiconductor fin may be a pFET fin and the third semiconductor fin may be an nFET fin.