A sigma-delta modulation device includes a detection circuit and a sigma-delta modulator. The detection circuit is configured to detect an input signal to generate a detection signal, and compare the detection signal and a threshold to generate a control signal. The sigma-delta modulator is coupled to the detection circuit and configured to store a plurality of noise transfer functions, select one of the noise transfer functions according to the control signal, and convert the input signal into an output signal according to the noise transfer function.

One example discloses a reconfigurable analog to digital converter (ADC) device, including: an analog front end (AFE) configured to receive a set of analog input signals and generate a corresponding set of digital output signals; wherein the AFE includes a set of reconfigurable ADC conversion circuits; and a sequencer coupled to the AFE and configured to control the set of reconfigurable ADC conversion circuits with a first AFE channel configuration at a first time and a second AFE channel configuration at a second time.

One example discloses a reconfigurable analog to digital converter (ADC) device, including: an analog front end (AFE) configured to receive a set of analog input signals and generate a corresponding set of digital output signals; wherein the AFE includes a set of reconfigurable ADC conversion circuits; and a sequencer coupled to the AFE and configured to control the set of reconfigurable ADC conversion circuits with a first AFE channel configuration at a first time and a second AFE channel configuration at a second time.

A sigma-delta modulation device includes a detection circuit and a sigma-delta modulator. The detection circuit is configured to detect an input signal to generate a detection signal, and compare the detection signal and a threshold to generate a control signal. The sigma-delta modulator is coupled to the detection circuit and configured to store a plurality of noise transfer functions, select one of the noise transfer functions according to the control signal, and convert the input signal into an output signal according to the noise transfer function.

An A/D conversion device, which operates in one mode including at least one of a ΔΣ mode, a cyclic mode, and a hybrid mode, includes: a first block that processes an analog input signal by a first amplifier; a second block including a second amplifier; a quantization unit that quantizes one of outputs of the first and second blocks; and a control circuit that switches the mode to perform a control corresponding to the mode.

A system may include an output stage for driving a load at an output of the output stage, a pulse-width modulation mode path configured to pre-drive the output stage in a first mode of operation, a linear mode path configured to pre-drive the output stage in a second mode of operation and a loop filter coupled at its input to the output of the output stage and coupled at its output to both of the pulse-width modulation mode path and the linear mode path. The pulse-width modulation mode path and the linear mode path may be configured such that a first transfer function between the output of the loop filter and the output of the output stage is substantially equivalent to a second transfer function between the output of the loop filter and the output of the output stage.

A sigma-delta analog-to-digital converter (ADC) is disclosed. The sigma delta ADC has an analog input and a digital output. A sigma-delta modulator input is coupled to the analog input and a sigma-delta modulator output. A first filter having a first filter input is coupled to the sigma-delta modulator output and a first filter output. A second filter having a second filter input is coupled to the sigma-delta modulator output and a second filter output. The sigma-delta ADC operates in a first and second mode. In a first mode, the first filter output is coupled to the digital output. In a second mode, the second filter output is coupled to the digital output.

An A/D conversion device, which operates in one mode including at least one of a mode, a cyclic mode, and a hybrid mode, includes: a first block that processes an analog input signal by a first amplifier; a second block including a second amplifier; a quantization unit that quantizes one of outputs of the first and second blocks; and a control circuit that switches the mode to perform a control corresponding to the mode.

A continuous-time (CT) delta-sigma modulator (DSM) based analog to digital converter (ADC) in a radio receive chain supports a wide range of data rates in a power efficient way in a small die area. The ADC utilizes a 2.sup.nd order loop-filter with a single-amplifier loop-filter topology using a two stage Miller amplifier with a feed forward path and a push-pull output stage. High bandwidth operations utilize a negative-R compensation scheme at the amplifier input. Negative-R assistance is disabled for low data rate applications. With the negative-R assistance disabled, loop-filter resistor values are increased, instead of only the loop filter capacitor values to scale the noise transfer function (NTF), thereby limiting the capacitor area needed and enabling lower power operation. The NTF zero location is programmable allowing the NTF zero to be located near the intermediate frequency for different bandwidths to reduce the DSM quantization noise contribution for narrow-band (low data rate) applications.

A sigma-delta analog-to-digital converter (ADC) is disclosed. The sigma delta ADC has an analog input and a digital output. A sigma-delta modulator input is coupled to the analog input and a sigma-delta modulator output. A first filter having a first filter input is coupled to the sigma-delta modulator output and a first filter output. A second filter having a second filter input is coupled to the sigma-delta modulator output and a second filter output. The sigma-delta ADC operates in a first and second mode. In a first mode, the first filter output is coupled to the digital output. In a second mode, the second filter output is coupled to the digital output.