Abstract: A disclosed embodiment is a circuit for producing a core clock from a system clock so that a core clock cycle is independent of a duty cycle of the system clock. The circuit comprises a system clock receiving sub-circuit for generating a first rising edge of the core clock, a core clock falling edge generation sub-circuit responsive to every rising edge of the core clock, and a self-triggering sub-circuit to trigger a second rising edge of the core clock so as to cause the core clock cycle to be independent of the system clock duty cycle. In one embodiment, the first core clock rising edge may be triggered in response to an initial system clock rising edge. In another embodiment, the first core clock rising edge may be triggered in response to an initial system clock falling edge. The core clock frequency may be twice the frequency of the system clock.