Electronic International Standard Serial Number (EISSN)
1350-911X
abstract
Dual slope ADCs have been shown to implement noise shaping when converted into integrating quantisers, turning amplitude information into time encoded pulses. A way to increase the resolution of an integrating quantiser is to use a gated ring oscillator (GRO) to estimate the pulse length. Such combination benefits from the noise shaping effect inherent to GROs. Hence, a noise shaping order increase can be achieved by a multistage configuration when an integrating quantiser is cascaded with a GRO. The architecture and behavioural simulation of such a MASH converter is discussed. Also, the on-line calibration of the noise cancellation filters is described.