Patent ID: 6384653
Filing Date: 2002-05-07
Classification: H03K

Abstract:
A method of providing a signal with at least one controllable zero crossing time value, the method comprising:providing a first time varying triangular wave train, having a selected period T, centered at zero amplitude and having a maximum amplitude value of A, where A is a selected number in the range 0&lE;A&lE;1 and can be varied; providing a second time varying triangular wave train, having the period T, shifted in phase from the first triangular wave train by a selected amount fÂ·T, centered at zero amplitude and having a maximum amplitude of 1âˆ’A, where f is a selected fraction satisfying 0choosing the fraction value f so that a sum of the first and second triangular wave trains has at least one positive value and has at least one negative value, within a selected time interval that is determined by the choice of f; and choosing the amplitude value A so that the sum of the first and second triangular wave trains has the at least one zero crossing value at a selected time value t=tz in the range 0&lE;tz&lE;T, where the time tz varies linearly with A within a selected time interval.