Abstract: An imaging device for generating an image signal includes an image sensing device for producing an image signal subject to one or more clock signals and a circuit for generating one or more of the clock signals, wherein the clock signal generating circuit is responsive to a programmable input signal for adjusting a duty cycle of at least one of the clock signals. In particular, by clocking two recirculating shift registers out of phase and parallel loading them with a programmable bit pattern to produce the output clock signals, the frequency of an input clock that is required to produce the output clock signals can be reduced by half.