A voltage level shifter module comprising at least one input arranged to receive an input signal, and at least one cascode transistor arranged to receive at a gate thereof at least one reference voltage signal. The voltage level shifter module further comprises at least one reference voltage control component arranged to detect logical state transitions within the input signal from at least a first logical state to a second logical state, and cause the reference voltage signal applied to the gate of the at least one cascode transistor to be pulled down to a reduced voltage upon detection of a logical state transition within the input signal from at least a first logical state to a second logical state.