A method and system of an analog to digital conversion having an exponential result are provided. An analog input signal is received by the ramp ADC. The analog input signal is converted into an N-bit digital signal having a linear relationship with the analog input signal. An internal gated clock signal is generated based on the received first clock signal. The gated clock signal is used as an input to an M-bit register. An output of the M-bit register is multiplied by a predetermined factor. The product of the multiplication is provided as an input to the M-bit register. The output of the M-bit register provides an M-bit output having an exponential relationship with the analog input signal.