Oscillators having charge/discharge circuits with adjustment to maintain desired duty cycles

An oscillator comprising:

• a comparator;
• first and second switches for alternately connecting first and second respective reference voltages to a first input of said comparator;
• a capacitor connected to a second input of said comparator;
• a current source and a current sink;
• third and fourth switches for alternately connecting said current source and said current sink, respectively, to said capacitor;
• and
• means for adjusting either said current source or said current sink to maintain desired duty cycles of high and low levels output from said comparator.

An oscillator comprising:

• a comparator;
• first and second switches for alternately connecting first and second respective reference voltages to a first input of said comparator;
• a capacitor connected to a second input of said comparator;
• a current source and a current sink;
• means for alternately connecting said current source and said current sink, respectively, to said capacitor;
• and
• means for adjusting said second reference voltage to maintain desired duty cycles of high and low levels output from said comparator.

A method for generating oscillations, said method comprising the steps of:

• alternately connecting first and second respective reference voltages to a first input of a comparator;
• coupling a capacitor to a second input of said comparator and alternately charging and discharging said capacitor between said first and second reference voltages to cause said comparator to alternately output high and low levels;
• and
• adjusting said second reference voltage to maintain desired duty cycles of said high and low levels output from said comparator.

A method for generating oscillations, said method comprising the steps of:

• alternately connecting first and second respective reference voltages to a first input of a comparator;
• coupling a capacitor to a second input of said comparator and, using a current source and current sink, alternately charging and discharging said capacitor between said first and second reference voltages to cause said comparator to alternately output high and low levels;
• and
• adjusting either said current source or said current sink to maintain desired duty cycles of said high and low levels output from said comparator.