Patent ID: 7863992

Claim:
An oscillator comprising: a first comparator circuit generating a first pulse when a frequency voltage reaches a first reference voltage; a second comparator circuit generating a second pulse when the frequency voltage reaches a second reference voltage; an oscillation signal generator circuit generating an oscillation signal by latching a first voltage in response to the first pulse and latching a second voltage in response to the second pulse; and a frequency voltage generator circuit raising or lowering the frequency voltage in response to the oscillation signal, wherein the driving capability of the first comparator circuit is reduced at the latching of the first voltage and is restored at the latching of the second voltage, and the driving capability of the second comparator circuit is reduced at the latching of the second voltage and is restored at the latching of the first voltage, wherein the first comparator circuit comprises a first pull-down driver for adjusting the driving capability thereof, and the second comparator circuit comprises a second pull-down driver for adjusting the driving capability thereof, wherein the first and second pull-down drivers are implemented using current sources.