It is possible to overdrive the internal reference of the CASR and CKSR models. This will change the zero-current output voltage. When raising or lowering the reference voltage, keep in mind 3 points: First, the output of the transducer will always be limited with a minimum of 0.375V and a maximum of 4.625V. Second, the measuring range will be determined by the maximum compensation current which is determined by the internal workings of the ASIC. A LEM applications engineer can help the designer determine what the maximum measuring range would be for a specific reference voltage. Third, the current source/sink of the Vref pin is based on its internal resistance, 680 Ω.