1. A method to achieve an exponential current digital-to-analog converter (IDAC) having improved accuracy using a binary-weighted most significant bit (MSB) comprising: defining a differential non-linearity (DNL); defining number of LSB bits needed for the targeted DNL with a binary weighted MSB; calculating the number of bits to be used for the binary-weighted MSB to get the desired IDAC base; deriving the minimum current for the Imax; defining the LSB as an exponential current mirror according to the specified relationship for the ILSB; and defining a binary weighted MSB according to the specified relationship for IMSB.