Patent ID: RE41830

Claim:
A delta-sigma modulator comprising: (a) a chopper-stabilized integrator including a plurality of chopper stabilization input switches coupled to an input of the integrator and a plurality of chopper stabilization output switches coupled to an output of the integrator; (b) a quantizer having an input coupled to the output of the integrator; (c) an input signal acquiring circuit controlled by a switched reference feedback circuit and having an output coupled to the input of the integrator; (d) a frequency-shaped pseudo-random chopper clock signal generator circuit including a pseudo-random sequence generator and producing a frequency-shaped pseudo-random clock signal; (e) resetting circuitry for resetting the pseudo-random sequence generator in synchronization with a digital output of the chopper-stabilized delta-sigma modulator to prevent wrap-around operation of the pseudorandom sequence generator; and (f) a logic circuit producing, in response to the frequency-shaped pseudo-random clock signal, chopper clock signals applied to control various ones of the chopper stabilization input switches and chopper stabilization output switches.