The output spectra of digital delta sigma modulators (DDSMs) are characterized by unwanted spurious periodic tones (spurs). Additive pseudorandom dither is used to whiten the quantization noise of the DDSM in order to minimize these spurs. Unfortunately, pseudorandom dither signals are themselves periodic and may cause other spurs to appear. This paper describes a DDSM architecture with multiple periodic dither inputs and explains the limits of its performance.