US Patent 7209069 Successive approximation analog-to-digital converter with current steered digital-to-analog converter

A successive approximation Analog-to-Digital Converter (“ADC”) having a successive approximation controller operably coupled to convert a control signal into a digital output of the successive approximation ADC, a current-steered Digital-to-Analog Converter operably coupled to convert the digital output of the successive approximation ADC into an analog feedback signal, and a comparator module operably coupled to compare the analog feedback signal with an analog input of the successive approximation ADC to produce the control signal. A further aspect is a method for increasing accuracy for a digital successive approximation of an analog input signal. The method includes determining a signal characteristic of the analog input signal to an Analog-to-Digital Converter (“ADC”), and selecting a reference voltage source of a Digital-to-Analog Converter of the ADC from a plurality of reference voltage sources based on the analog input signal.