STRING DAC CHARGE BOOST SYSTEM AND METHOD
First Claim
1. A string digital to analog converter (DAC), comprising:
- an impedance network comprising a first and second impedance strings;
a set of switches to couple a first voltage across the first impedance string to the second impedance string in a first code configuration and to couple a second voltage across the first impedance sting to the second impedance string in a second code configuration; and
a charge boost circuit to inject a boost charge into the impedance network during a transition between the first code configuration and the second code configuration.
4 Assignments
0 Petitions
Accused Products
Abstract
Embodiments of the present invention may provide a string DAC with charge boosting. The string DAC may include multiple strings, such as an MSB DAC and an LSB DAC, for converting a digital word into a corresponding analog voltage. The string DAC may also include a charge boost system to couple a charge into or out of the DAC during a code transition, such as a MSB code transition. The string DAC may operate in a break-before-make connection technique where all relevant connections are substantially open-circuited before new connections are made. Therefore, the charge boost may shorten the settling time of impedance elements in the string DAC between code transitions and may substantially reduce (or eliminate) glitches.
-
Citations
24 Claims
-
1. A string digital to analog converter (DAC), comprising:
-
an impedance network comprising a first and second impedance strings; a set of switches to couple a first voltage across the first impedance string to the second impedance string in a first code configuration and to couple a second voltage across the first impedance sting to the second impedance string in a second code configuration; and a charge boost circuit to inject a boost charge into the impedance network during a transition between the first code configuration and the second code configuration. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
-
-
14. A string digital to analog converter (DAC), comprising:
-
an impedance network comprising a first and second impedance strings; a set of switches to couple a first voltage across the first impedance string to the second impedance string in a first code configuration and to couple a second voltage across the first impedance sting to the second impedance string in a second code configuration; and a charge boost circuit to inject a charge after a transition between the first code configuration and the second code configuration. - View Dependent Claims (15, 16, 17)
-
-
18. A method of converting two digital signals into respective analog signals, comprising:
-
converting a first digital signal into a first analog signal using a multi-string DAC; converting a second digital signal into a second analog signal using the multi-string DAC; and injecting a boost charge signal into the multi-string DAC during a transition between the first and second digital signal conversions. - View Dependent Claims (19, 20, 21)
-
-
22. A string digital to analog converter (DAC), comprising:
-
a resistive network comprising a first and second resistor strings, each string comprising a plurality of series-coupled resistors; a switch array selectively connecting intermediate nodes in the first resistor string to terminal ends of the second resistor string, the switch array responsive to input control codes to configure the selective connections between the first and second resistor string; and a charge boost circuit to inject a charge into the string DAC during a transition between a first control code and a second control code. - View Dependent Claims (23, 24)
-
Specification