This document concerns the deviation of the output of MilliNewton and CentoNewton force sensors from ideal ratiometric behaviour. These sensors nominally operate from a single +5 V supply voltage and, as they have no voltage regulator, their output response should be ideally "ratiometric", i.e. proportional to supply voltage, within the operating range of the used amplifier chip. However, due to the amplifier characteristics (nonlinear offset), a substantial deviation of the sensor offset (zero-load output) from this ideal behaviour can appear if the supply voltage strongly deviates from 5 V. On the other hand, the span remains essentially ratiometric, and sensor functionality is maintained.