Asynchronous successive approximation analog-to-digital converter

An analog-to-digital converter for converting an analog input signal to an N-bit binary coded output signal, said converter comprising:

• input means for receiving an analog input signal;
• output means for supplying an N-bit binary coded output;
• and
• a network including N amplifiers, each of said amplifiers providing an output for one bit of the binary coded output wherein each of said amplifiers receives an input which includes a combination of said analog input signal and a feedback output signal from each of the amplifier outputs which provides a more significant bit of the binary output signal;
• and wherein each of said feedback output signals are tapped from the output of an associated amplifier and scaled in proportion to the significance of the binary bit provided by that associated amplifier.

A method for converting an analog signal to an N-bit binary representation thereof, said method comprising:

• receiving an analog input signal;
• applying scaled analog input signals to inputs of N-inverting amplifiers, each of said inverting amplifiers providing one bit of said N-bit binary output;
• and
• subtracting feedback signals from said analog input signal to thereby provide for each of said scaled analog input signals, each of said feedback signals including the output from each of associated inverting amplifiers which provide for a more significant bit of the binary output, and which feedback signals are scaled in proportion to the binary significance provided by said associated inverting amplifier.