Data-driven voltage regulator

• US 9,985,634 B2
• Filed: 08/27/2014
• Issued: 05/29/2018
• Est. Priority Date: 05/20/2010
• Status: Active Grant

• Current Assignee: Kandou Labs, SA
• Original Assignee: Kandou Labs, SA
• Inventors: Ulrich, Roger
• Primary Examiner(s): Onat, Umut
• Application Number:
  US14/470,795
• Publication Number:
  US 20150066230A1
• Time in Patent Office: 1,371 Days
• CPC Class Codes: H02M 3/07 using capacitors charged and discharged alternately by semiconductor devices with control electrode , e.g. charge pumps
• CPC Class Codes: H03K 19/018514 with at least one differential stage H03K19/018528 and H03K19/018542 take precedence
• CPC Class Codes: H04L 25/0272 Arrangements for coupling to multiple lines, e.g. for differential transmission
• CPC Class Codes: H04L 25/028 Arrangements specific to the transmitter end
• CPC Class Codes: H04L 25/4917 using multilevel codes

Abstract

An efficient regulated power supply for a communications interface is disclosed using a data-dependent charge pump design. Data patterns known to produce increased power supply load concurrently raise power supply source current, leading to significant overall power savings for the combined communications driver and regulator over known switched and linear regulator solutions.

Claims

1. An apparatus comprising:

an energy storage element;

a control circuit configured to determine respective magnitudes of one or more signal transmission level changes associated with one or more communications interface output drivers in response to a change in input data, and to responsively provide one or more data-driven charge pump control signals and one or more driver control signals;

a data-driven charge pump circuit comprising one or more charge pump circuits each having a control input node for receiving a respective data-driven charge pump control signal of the one or more data-driven charge pump control signals, each charge pump circuit being configured to selectively pre-charge the energy storage element in response to the respective data-driven charge-pump control signal applied to the control input node by transferring a respective amount of charge to the energy storage element, the respective amount of charge transferred indicative of the respective magnitude of a corresponding signal transmission level change; and

the one or more communications interface output drivers each connected to (i) a respective signal line of a set of one or more signal lines and (ii) the energy storage element, each communications interface output driver configured to receive a corresponding driver control signal and to selectively transfer a portion of charge stored in the energy storage element to the respective signal line in response to the corresponding driver control signal.

2. The apparatus of claim 1, wherein the control circuit is configured to receive transmit data and transmit clock signals to determine the respective magnitudes of the one or more signal transmission level changes.

3. The apparatus of claim 2 wherein the transmit data signals include even data signals and odd data signals, and the control circuit is configured to determine the respective magnitudes of the signal transmission level changes between the even data signal and a subsequent odd data signal and between the odd data signal and a subsequent even data signal.

4. The apparatus of claim 3 further comprising a data multiplexer circuit having a multiplexed output connected to the one or more communications interface output drivers, and configured to combine the even data signals and odd data signals into a single data stream.

5. The apparatus of claim 1 wherein the determined magnitude of a given signal transmission level change is a low-to-high transition, and at least one charge pump circuit is configured to charge a capacitor in the energy storage element during a signaling interval not associated with a low-to-high transition.

6. The apparatus of claim 1 further comprising a voltage regulator connected to the energy storage element to maintain a desired voltage at the energy storage element.

7. The apparatus of claim 1 further comprising a comparator having a first input connected to the energy storage element and a second input connected to a reference voltage signal and a comparator output connected to the control circuit, wherein the control circuit initiates one or more charge pump cycles in response to the to the comparator output.

8. The apparatus of claim 1 wherein each of the one or more communications interface output drivers shares a single energy storage element, and wherein the control circuit is configured to provide a data-driven charge pump control signal only to charge pumps associated with communications interface output drivers having a low-to-high signal transmission level change.

9. A method comprising:

detecting, using a control circuit, a predetermined data sequence within a received data signal associated with a low-to-high signal transmission level change on at least one of the one or more signal lines;

responsive to detecting the predetermined data sequence, providing data-driven charge pump control signals to a data-driven charge pump to pre-charge an energy storage element with an amount of energy determined by the low-to-high signal transmission level change on the at least one of the one or more signal lines; and

outputting signal transmission levels from an output driver over the one or more signal lines, wherein the output driver uses energy selectively transferred from the energy storage element for establishing at least one low-to-high signal transmission level change on the one or more signal lines.

10. The method of claim 9, wherein the data signal includes even data signals and odd data signals, and the predetermined data sequence is a predetermined change between the even data signal and a subsequent odd data signal or a predetermined change between the odd data signal and a subsequent even data signal.

11. The method of claim 9 further comprising multiplexing even data signals and odd data signals into a single data stream.

12. The method of claim 9 further comprising using a voltage regulator connected to the energy storage element to maintain a desired average voltage at the energy storage element.

13. The method of claim 9 further comprising:

generating a comparison signal between a voltage associated with the energy storage element and a reference voltage signal; and

initiating one or more charge pump cycles in response to the comparison signal.

14. The method of claim 9 wherein providing the data-driven charge pump control signals comprises combining at least one clock signal with a logic circuit output indicative of a low-to-high transmission signal level change.