Patent ID: 7750751
Filing Date: 2010-07-06
Classification: H03K,H04L

Abstract:
1. A phase modulation circuit, comprising: a sampling circuit operative to provide a fixed edge differential signal in response to an input signal; at least two edge shaping circuits, each coupled to a respective leg of the differential signal, operative to provide a corresponding shaped signal having a fixed rise/fall time. at least two modulation circuits operative to simultaneously provide phase modulated versions of the differential signal in response to an adjustable modulation input signal; and an output circuit operative to provide a phase modulated copy of the input signal in response to the modulated versions of the differential signal; and wherein the at least two modulation circuits further includes a t-type flip flop operative to sample and provide the shaped non-inverted signal in response to the modulation input signal, such that the t-type flip flop will toggle on the rising edge of the non-inverted signal upon a predetermined voltage transition measured as the difference between the non-inverted signal voltage and the modulation input signal voltage.