Abstract: Spread spectrum clock generation (SSCG) using asymmetric triangular profiles to reduce electromagnetic interference (EMI). The asymmetric triangular profiles provide better peak power attenuation and a more uniform power spectrum spread than conventional symmetric triangular profiles. The method receives a first clock signal that has a first frequency spectrum and modulates it with an asymmetric triangular profile to produce a second clock signal. The second clock signal has a wider frequency spectrum than the first clock signal and results in reduced electromagnetic interference compared with the first clock signal.

Abstract: A circuit having multiple overlapped feedback loops for DC offset cancellation is provided with applying in one of multistage amplifier, multistage filter, and the combination thereof. The circuit includes a plurality of negative feedback variable bandwidth switches coupled to each stage of the above mentioned multistage devices, the output of the last stage is coupled to an input of a low-pass filter loop. The circuit includes a plurality of variable gain amplifiers, output of each variable gain amplifier is coupled to the series contact of each stage respectively, and input of each variable gain amplifier is thereof coupled to an output of the low-pass filter loop. Therefore, the circuit achieves to cancel the DC offset for multistage overlapped feedback path with less area and low power consumption.

Abstract: Spread spectrum clock generation (SSCG) using asymmetric triangular profiles to reduce electromagnetic interference (EMI). The asymmetric triangular profiles provide better peak power attenuation and a more uniform power spectrum spread than conventional symmetric triangular profiles. The method receives a first clock signal that has a first frequency spectrum and modulates it with an asymmetric triangular profile to produce a second clock signal. The second clock signal has a wider frequency spectrum than the first clock signal and results in reduced electromagnetic interference compared with the first clock signal.