DERIVING POWER OUTPUT FROM AN ENERGY HARVESTER

• US 20170271873A1
• Filed: 03/21/2016
• Published: 09/21/2017
• Est. Priority Date: 03/21/2016
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Huang, Lilly, Schaef, Christopher, Vaidya, Vaibhav, Kim, Suhwan
• Granted Patent: US 10,615,685 B2
• Time in Patent Office: Days
• CPC Class Codes: H02J 50/001 Energy harvesting or scavenging
• CPC Class Codes: H02J 7/34 Parallel operation in networks using both storage and other dc sources, e.g. providing buffering H02J7/14 takes precedence
• CPC Class Codes: H02M 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• 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: H02M 3/1582 Buck-boost converters H02M3/1584 takes precedence

Abstract

Apparatuses, methods and storage medium associated with deriving power output from an energy harvester are disclosed herein. In embodiments, an apparatus may include one or more processors, devices, and/or circuitry to identify a plurality of times at which an intermediate voltage of a two stage power conversion circuit corresponds to a voltage reference, and ascertain an amount of time between one of the identified times and another one of the identified times. The one or more processors, devices, and/or circuitry may derive a power or current value associated with the second power supply using the amount of time.

Claims

1. A system, comprising:

a voltage regulation circuit to receive one or more first power supplies from one or more energy harvester sources and to generate an intermediate voltage, the voltage regulation circuit having one or more input terminals coupled to the one or more first power supplies;

a switched capacitor charge pump to receive the intermediate voltage and to generate a second power supply; and

power management circuitry to;

identify a plurality of times at which the intermediate voltage corresponds to a voltage reference;

ascertain an amount of time between one of the identified times and another one of the identified times;

derive a power or current value associated with the second power supply using the amount of time; and

output the derived power or current value or store the derived power or current value in a memory device.

2. The system of claim 1, wherein the power management circuitry includes a digital counter.

3. The system of claim 2, wherein the power management circuitry includes a pulse width modulator to receive an output of the digital counter.

4. The system of claim 1, wherein the power management circuitry includes an analog circuit component, the power management circuitry to ascertain the amount of time using the analog circuit component.

5. The system of claim 4, wherein the analog circuit component includes at least one of an analog integration sawtooth charge pump or a voltage-controlled oscillator.

6. The system of claim 1, wherein the identified times correspond to different switching cycles of the switched capacitor charge pump.

7. The system of claim 1, wherein the identified times include a beginning of a charging of a capacitor of the switched capacitor charge pump and an end of a different charging of the capacitor.

8. The system of claim 1, the power management circuitry to ascertain an amount of time between a discharge of a capacitor of the switched capacitor charge pump and a time of a subsequent discharge of the capacitor.

9. The system of claim 1, the power management circuitry to:

initiate a digital counter at a time corresponding to a discharge of a capacitor of the switched capacitor charge pump; and

read a count of the digital counter at a time corresponding to the latter of two next discharges of the capacitor; and

ascertain the amount of time based on said count.

10. The system of claim 1, wherein a frequency of operation of the voltage regulation circuit is greater than a frequency of operation of the switched capacitor charge pump.

11. A method, comprising:

identifying a plurality of times at which an intermediate voltage corresponds to a voltage reference, the intermediate voltage corresponding to a node between a plurality of stages of a plural-stage power conversion circuit;

ascertaining an amount of time between one of the identified times and another one of the identified times;

deriving a power or current value at one or more outputs of one or more energy harvester sources using a result of the ascertainment; and

outputting the derived power or current value or storing the derived power or current value in a memory device.

12. The method of claim 11, further comprising:

initiating a count at a time corresponding to a discharge of a capacitor of the switched capacitor charge pump; and

reading a value of the count at a time corresponding to the latter of two next discharges of the capacitor; and

ascertaining the amount of time based on said read value.

13. The method of claim 11, wherein the derived power or current value represents an indirect measurement of an electrical characteristic of the output of the one or more energy harvester sources.

14. The method of claim 13, wherein the measurement is obtained without sensing the electrical characteristic.

15. The method of claim 11, further comprising:

acquiring energy from the one or more harvesting sources;

converting the acquired energy into one or more power supplies; and

powering an input of a first stage of the plural-stage power conversion circuit using the one or more of power supplies;

wherein the one or more energy conversion sources includes at least one of a photovoltaic (PV) cell, a thermoelectric generator (TEG), a radio frequency (RF) device, or a piezoelectric material.

16. Power management circuitry, comprising:

a comparator having a plurality of inputs including a voltage reference and an intermediate voltage corresponding to a node between a plurality of stages of a plural-stage power conversion circuit;

a digital counter having a plurality of inputs including a clock and an input coupled to an output of the comparator; and

a power management module to;

initiate and read the digital counter based on an output of the comparator;

determine an amount of time based on count information of the digital counter; and

derive a power or current value at the output of one or more energy harvester sources based on the determined amount of time.

17. The power management circuitry of claim 16, further comprising a pulse width modulator to receive an output of the digital counter.

18. The power management circuitry of claim 16, the power management module to initiate the digital counter and read the digital counter during different switching cycles of the switched capacitor charge pump.

19. The power management circuitry of claim 16, the power management module to:

initiate the digital counter at a time corresponding to a discharge of a capacitor of the switched capacitor charge pump; and

read a count of the initiated digital counter at a time corresponding to the latter of two next discharges of the capacitor; and

determine the amount of time based on said count.

20. The power management circuitry of claim 16, further comprising:

one or more energy conversion devices to acquire energy from the one or more of energy harvester sources and to convert the acquired energy into one or more power supplies;

wherein the one or more energy conversion sources includes at least one of a photovoltaic (PC) cell, a thermoelectric generator (TEG), a radio frequency (RF) device, or a piezoelectric material.