A delta modulation type data converter is adapted to carry out signal processing by sequentially comparing in cycles an inputted signal with a reference voltage set according to the results of previous comparisons and includes a plurality of current sources, switch circuits for setting a current value by appropriately selecting one or more of these current sources, an integrator circuit for generating the reference voltage according to a specified current value, and a control circuit for controlling the switch circuits to make an appropriate selection of these current sources according to the result of a comparison between the reference voltage and the inputted analog signal. The control circuit controls the switch circuits such that, if the result of comparison is the same as in the precious cycle, a selection from the current sources is made such that the current value will be increased, provided such selection is possible. If the result of comparison is inverted from the previous cycle, a selection is made such that the current direction with respect to the integrator circuit is reversed. If the result of comparison is inverted repeatedly for a specified plural number of cycles, a selection is made such that the current direction with respect to integrator circuit is reversed and the associated current value is reduced, provided such selection is possible. The plurality of current sources may include a first group connected to a source voltage and a second group connected to a reference voltage source, the current sources in each group having associated therewith current values which differ by a factor of 2 from one to another.
展开▼
