Enhanced second order noise shaped segmentation and dynamic element matching technique

A multi-bit digital to analog converter comprising:

• a plurality of unit cells, each providing an electrical signal to a common output at multiple levels in response to a respective control signal;
• a control system having multiple layers of branch circuits, each branch circuit comprising:
• a dynamic element matching circuit receiving a plurality of least significant bits of the input code to generate respective output signals to the control system;
• a plurality of branches, each receiving most significant bits of an input code to the respective layer and having an adder for the most significant bits of the layer's input signal and a respective output from the dynamic element matching circuit;
• wherein:
• an input signal to the digital to analog converter is input to a first layer as that layer's input code,
• input codes of the other layers are taken from output signals of preceding layers, and
• output signals of a last layer may be input to the unit cells as control signals.

A multi-bit digital to analog converter comprising:

• a first layer comprising:
• a first control system including four first layer branches, each branch receiving three most significant bits of an input signal and providing a first layer output signal,
• a first layer dynamic element matching circuit performing dynamic element matching based on the two least significant bits of the input signal and adding values to at least one of the first layer branches, and
• a dynamics enhancement circuit to increase data activity in the first layer output signals by adding values to the first layer branches, if it is determined that there is insufficient data activity in the input signal;
• and
• a second layer comprising four clusters of outputs, each cluster coupled to one of the first layer branches to receive one of the first layer output signals, each cluster of outputs comprising:
• a second layer control system including four second layer branches, each branch receiving the two most significant bits of the first layer output signal and providing a second layer control signal,
• a second layer dynamic element matching circuit performing dynamic element matching based on the least significant bits of the first layer output signal and adding values to at least one of the control signals in the second layer branches, and
• four three level unit elements coupled to the second layer branches providing control signals.

A method to perform noise shaped splitting of a digital input signal, comprising:

• distributing the most significant bits of the input signal to a plurality of branches of a control system;
• performing dynamic element matching based on the values of the least significant bits of the input signal;
• adding the results of the dynamic element matching to the plurality of branches;
• determining if there is insufficient data activity in the input signal;
• if it is determined that there is insufficient data activity in the input signal, performing dynamics enhancement by adding values to the plurality of branches to increase the data activity while maintaining the digital value unchanged.