TREE STRUCTURED SUPPLY AND BIAS DISTRIBUTION LAYOUT

• US 20130222167A1
• Filed: 02/24/2012
• Published: 08/29/2013
• Est. Priority Date: 02/24/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Keramat, Mansour, Chao, Yuan-Ju
• Granted Patent: US 8,610,612 B2
• Time in Patent Office: Days
• US Class Current: 341/148
• CPC Class Codes: H03M 1/685 the quantisation value generators of both converters being arranged in a common two-dimensional array
• CPC Class Codes: H03M 1/687 Segmented, i.e. the more significant bit converter being of the unary decoded type and the less significant bit converter being of the binary weighted type
• CPC Class Codes: H03M 1/745 with weighted currents
• CPC Class Codes: H03M 1/747 with equal currents which are switched by unary decoded digital signals
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

Systems and methods are disclosed for performing data conversion by matching current sources using a thin oxide device; and minimizing voltage stress on the thin oxide device during operation or power down.

Claims

1. A power supply distribution system for a data converter, comprising:

a power supply pad to receive power;

a power bus coupled to the power supply pad;

a multi-tiered tree structure set of power distribution lines coupled to the power bus to provide supply and bias power distribution in the data converter, wherein the tree structure includes at least a top tier set of power distribution trunks each supplying power to different bottom tier set of power connections; and

an array of current sources having at least a row or a column powered by the bottom tier set of power connections.

2. The system of claim 1, comprising:

a second power bus coupled to the power supply pad; and

a second multi-tiered tree structure set of power distribution lines coupled to the second power bus to provide supply and bias power distribution, wherein the second tree structure includes at least a top tier set of power distribution trunks each supplying power to different bottom tier set of power connections, and wherein the second multi-tiered tree structure feeds a row of the array of current sources while the first multi-tiered tree structure feeds a column of the array of current sources.

3. The system of claim 1, wherein the current cell comprises a current source or a current sink.

4. The system of claim 1, wherein the current cell comprises a cascoded source or double cascaded source.

5. The system of claim 1, wherein the current cell comprises a cascoded sink or double cascaded sink.

6. The system of claim 1, comprising a diode coupled to the array of current sources and the power supply pad and wherein a cell current I_cell is defined as:

7. The system of claim 1, comprising;

a plurality of supply lines, wherein the supply lines for row (N) and row (N+1) are joined together to form a first master rail, with N being an odd number; and

a second master rail coupled to a plurality of first master rails.

8. The system of claim 7, wherein each row comprises equal spacing and distance layout, and wherein a current cell in each row on one column has the same power (IR) drop from the power supply pad.

9. The system of claim 1, comprising a unifier coupled to the power bus and a current steering digital to analog converter and wherein the unifier eliminates a second order effect of power (IR) drop.

10. The system of claim 1, wherein the set comprises one multi-tiered tree structure for each of a supply voltage input, a bias voltage input, and a cascoded bias voltage input.

20. The system of claim 1, comprising forming one multi-tiered tree structure for each of a supply voltage input, a bias voltage input, and a cascoded bias voltage input.

11. A method for distributing power supply in a data converter, comprising:

fabricating a power bus coupled to a power supply pad to receive power;

fabricating a multi-tiered tree structure set of power distribution lines and connecting a top tier to the power bus in the data converter;

distributing power from the power us through a top tier set of power distribution trunks each supplying power to different bottom tier set of power connections; and

powering an array of current sources having at least a row or a column powered by the bottom tier set of power connections.

12. The method of claim 11, comprising:

providing a second power bus coupled to the power supply pad;

fabricating a second multi-tiered tree structure set of power distribution lines coupled to the second power bus to provide supply and bias power distribution;

providing power to the first multi-tiered tree structure to supply a column of the array of current sources; and

providing power to the second multi-tiered tree structure to supply a row of the array of current sources.

13. The method of claim 11, wherein the current cell comprises a current source or a current sink.

14. The method of claim 11, wherein the current cell comprises a cascoded source or double cascaded source.

15. The method of claim 11, wherein the current cell comprises a cascoded sink or double cascaded sink.

16. The method of claim 11, comprising connecting a diode to the array of current sources and the power supply pad and wherein a cell current I_cell is defined as:

17. The method of claim 11, comprising;

forming a plurality of supply lines, wherein the supply lines for row (N) and row (N+1) are joined together to form a first master rail, with N being an odd number; and

forming a second master rail coupled to a plurality of first master rails.

18. The method of claim 17, wherein each row comprises equal spacing and distance layout, and wherein a current cell in each row on one column has the same power (IR) drop from the power supply pad.

19. The method of claim 11, comprising forming a unifier coupled to the power bus and a current steering digital to analog converter and wherein the unifier eliminates a second order effect of power (IR) drop.