US Patent 7480155 Digital generator of phase shift modulation

A digital generator of phase shift modulation receives two binary coded numbers (F) and (P), that represent a requested frequency value and a requested phase value, respectively, and generates two pairs of phase-shifted signals a, b and c, d. One pair of the phase-shifted signals is intended to control one half bridge of a full-bridge converter, and the second pair is intended to control the other half bridge. Signal b is complementary to signal a having a 50% duty cycle with addition of dead times created by a first delay line (5). Signals c and d have the same parameters as signals a and b, with the exception that dead times are created by a second delay line (6). The frequency of generated signals is proportional to the requested frequency value (F) and the phase shift between pairs of signals is proportional to the requested phase value (P).