Current Source Set Selection for Monotonic DAC Output

The patent applies preliminary action by performing a sorting operation on all current sources before they are selected for output. The sorting is done in advance based on measured current intensities, creating a predetermined order that ensures monotonic current output. This preliminary sorting prevents the non-monotonic behavior that would occur with random selection, as the current sources are already arranged in the correct sequence before selection occurs.

The patent changes the parameter of current source selection from random to sorted order based on measured current intensities. By measuring the actual current intensity of each current source and arranging them in sorted order, the system transforms the selection process to ensure that enabling current sources in sequence produces a monotonically increasing output current, directly addressing the linearity issue.

The patent changes the selection parameter from random or uniform selection to sorted selection based on measured current intensities. This parameter change allows the system to utilize current sources with varying actual magnitudes while maintaining linearity, as the sorting ensures that current sources are enabled in order of their actual current output, producing a monotonically increasing analog output that linearly corresponds to the digital input.

The patent employs feedback by measuring the actual current intensity of each current source and using this measurement information to determine the selection order. The measured current values feed into the sorting process, creating a closed-loop system that adapts to process variations and ensures accurate linear correspondence between digital input and analog output despite manufacturing variations.

The patent applies segmentation by dividing the sorted current sources into multiple groups or sets. This segmentation allows for more flexible control and selection strategies, where current sources within each group can be managed separately. The segmentation reduces integral nonlinearity errors by organizing current sources with similar characteristics together, while still maintaining the overall sorted structure for monotonic output.

The patent reduces device complexity by performing the sorting operation preliminarily and storing the sorted order information. Once sorted, the system can use this pre-established order for selection without needing complex real-time sorting logic during operation. The preliminary sorting simplifies the control structure by providing a fixed, predetermined selection sequence that can be implemented with simpler control circuitry.