WO1998020616B1

WO1998020616B1 - A method and device to provide a high-performance digital-to-analog conversion architecture

Info

Publication number: WO1998020616B1
Application number: PCT/SE1997/001672
Authority: WO
Filing date: 1997-10-07
Publication date: 1998-06-18

Abstract

High-speed and high accuracy digital-to-analog (D/A) converters find many applications in signal processing. For wideband telecommunication systems, there is a strong demand on high-performance D/A converters. With the design of the present invention it is enabled to prevent distortions and intermodulations for high-speed and high-accuracy digital-to-analog (D/A) converters for telecommunication applications, where the requirements on distortion and intermodulation can be very stringent. By combining segmentation for MSBs and binary weighting for LSBs a high-performance digital-to-analog conversion architecture can be achieved, where a delay for the binary weighted LSBs is used to equalize a delay introduced by segmentation and where all bit switches (14) are clocked with a tree-like-clock distribution network (11). New floor plans for CMOS, BiCMOS and bipolar implementation are thus invented and circuits for CMOS bit switches and current sources are also disclosed.

Claims

AMENDED CLAIMS[received by the International Bureau on 29 April 1998 (29.04.98); original claim 7 amended; remaining claims unchanged (2 pages)]

1. A method to provide a high-performance digital-to-analog conversion architecture by combining segmentation for MSBs and binary weighting for LSBs, c h a r a c t e r i z e d by using a delay for the binary weighted LSBs to equalize a delay introduced by the segmentation and -by clocking all bit switches with a tree- like clock distribution network.

2. The method according to claim 1, c h a r a c t e r i z e d by a CMOS implementation and densely laying out only current sources to increase matching and to decrease glitch energy and by organizing the bit switches and this associated clocking circuit in such a way that the delay from the clock input to every bit switch is identical.

3. The method according to claim 1, c h a r a c t e r i z e d by a BiCMOS and bipolar implementation and densely laying out current sources to increase matching and to decrease glitch energy and by organizing the bit switches and their associated clocking circuit in such a way 'that the delay from the clock input to every bit switch is identical.

4. A device to provide a high-performance digital-to-analog conversion architecture by combining segmentation for MSBs and binary weighting for LSBs, c h a r a c t e r i z e d in that a delay function is provided for the binary weighted LSBs to equalize a delay introduced by the segmentation and in that all bit switches (14) are provided to be clocked with a tree-like- clock distribution network (11) .

5. The device according to claim 4, c h a r a c t e r i z e d in that a CMOS implementation is provided, in that current sources are densely laid out to increase matching and to decrease glitch energy and in that bit switches and their associated clocking circuit are organized in such a way that the delay from the clock input to every bit switch is identical.

6. The device according to claim 4, c h a r a c t e r i z e d in that a BiCMOS and bipolar implementation are provided, in that current sources are densely laid out to increase matching and to decrease glitch energy and in that bit switches and their associated clocking circuit are organized in such a way that the delay from the clock input to every bit switch is identical.

7. The device according to claim 4, characterized in that a circuit realization for CMOS bit switches and current sources by using p-type transistors as current transistors and n-type transistors as switch, by scaling bit switches as currents are scaled and by adding dummy switch to ensure equal load for bit switch driver.