Graceful energization and degradation of an electronic device micropowered by a source of energy in its environment, particularly an irrigation controller powered by light energy
First Claim
1. An electrical device powered from a source of energy and accruing energy from the source so as to come, over time, from an inoperative un-powered to an operative powered condition, the device comprising:
- a storage-and-supply means for receiving and for storing energy from the source of energy, and for producing an unregulated electrical supply voltage that increases proportionately to the amount of energy stored;
a regulator means, receiving the unregulated supply voltage from the storage-and-supply means, for producing a regulated electrical supply voltage;
a power monitor circuit means, receiving the unregulated supply voltage from the storage-and-supply means,for remaining somnolent, howsoever long, until a time that the unregulated supply voltage reaches a first voltage level,for internally assuming a reset condition during a period, howsoever long, between the time that the unregulated supply voltage reached the first voltage level and until a time that the unregulated supply voltage reaches a second voltage level greater than the first voltage level, at which time the internal reset condition is dropped, andfor producing a logic true condition of a very-low-voltage status signal, indicative that unregulated supply voltage is at a very low level, during a period, howsoever long, between the time that the unregulated supply voltage reached the second voltage level and until a time that the unregulated supply voltage reaches a third voltage level greater than the second voltage level, at which time the very-low-voltage status signal assumes the logic false condition;
for producing a logic true condition of a low-voltage status signal, indicative that unregulated supply voltage is at a low level, during a period, howsoever long, between the time that the unregulated supply voltage reached the third voltage level and until a time that the unregulated supply voltage reaches a fourth voltage level greater than the third voltage level, at which time the low-voltage status signal assumes the logic false condition;
a functional circuit means, operative at a relatively higher voltage than is the power monitor circuit means, receiving the regulated supply voltage from the regulator means and also the very-low-voltage and the low-voltage status signals from the power monitor circuit means,for remaining somnolent until the received regulated supply voltage reaches a voltage level greater than the second voltage level but less than the fourth voltage level, at which time sufficient operability is achieved that the conditions of the status signals are regarded, andif the very-low-voltage status signal is in the logic true condition, which necessarily means that the low-voltage status signal is also in the logic true condition, then simply waiting and forebearing to do anything that would consume more than minimum power, butif the very-low-voltage status signal is in the logic false condition while the low-voltage status signal is in the logic true condition, then performing only limited housekeeping operations while consuming but slight power, butif both the very-low-voltage and the low-voltage status signals are in the logic false condition, then performing functional operations, consuming during the course of so doing all such power as the performed operations require.
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Accused Products
Abstract
An electronic device, for example an irrigation controller, accumulates energy from a source of energy, for example from incident light, in order to progress, over time, from an inoperative un-powered to an operative powered condition in a positively controlled, graceful and orderly manner. The device so progresses to operability regardless that it should, from time to time and at times, be totally devoid of energy, and regardless that it may accrue energy only but exceedingly slowly over periods of days, weeks and longer. A power monitor circuit of the device is made from an electrical circuit technology that is reliably operative at a relatively low voltage level, typically from BICMOS technology, whereas other device electrical circuits are operative only at a relatively higher voltage level, and are typically made from CMOS technology. When power is marginal the low-operational-voltage energy monitoring circuit reliably produces one or more status signals well before the other, higher-operational-voltage, circuits even commence to operate. Conversely to its graceful energization, the electronic device degrades and de-energizes gracefully and progressively, in stages. In particular, a microprocessor-based irrigation controller closes all controlled irrigation valves before, in the face of declining energy, reverting first to housekeeping at minimal energy consumption, and then, with further diminishing power, to dormancy. The controller will re-assume full operability should energy balances ever again so permit.
87 Citations
10 Claims
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1. An electrical device powered from a source of energy and accruing energy from the source so as to come, over time, from an inoperative un-powered to an operative powered condition, the device comprising:
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a storage-and-supply means for receiving and for storing energy from the source of energy, and for producing an unregulated electrical supply voltage that increases proportionately to the amount of energy stored; a regulator means, receiving the unregulated supply voltage from the storage-and-supply means, for producing a regulated electrical supply voltage; a power monitor circuit means, receiving the unregulated supply voltage from the storage-and-supply means, for remaining somnolent, howsoever long, until a time that the unregulated supply voltage reaches a first voltage level, for internally assuming a reset condition during a period, howsoever long, between the time that the unregulated supply voltage reached the first voltage level and until a time that the unregulated supply voltage reaches a second voltage level greater than the first voltage level, at which time the internal reset condition is dropped, and for producing a logic true condition of a very-low-voltage status signal, indicative that unregulated supply voltage is at a very low level, during a period, howsoever long, between the time that the unregulated supply voltage reached the second voltage level and until a time that the unregulated supply voltage reaches a third voltage level greater than the second voltage level, at which time the very-low-voltage status signal assumes the logic false condition; for producing a logic true condition of a low-voltage status signal, indicative that unregulated supply voltage is at a low level, during a period, howsoever long, between the time that the unregulated supply voltage reached the third voltage level and until a time that the unregulated supply voltage reaches a fourth voltage level greater than the third voltage level, at which time the low-voltage status signal assumes the logic false condition; a functional circuit means, operative at a relatively higher voltage than is the power monitor circuit means, receiving the regulated supply voltage from the regulator means and also the very-low-voltage and the low-voltage status signals from the power monitor circuit means, for remaining somnolent until the received regulated supply voltage reaches a voltage level greater than the second voltage level but less than the fourth voltage level, at which time sufficient operability is achieved that the conditions of the status signals are regarded, and if the very-low-voltage status signal is in the logic true condition, which necessarily means that the low-voltage status signal is also in the logic true condition, then simply waiting and forebearing to do anything that would consume more than minimum power, but if the very-low-voltage status signal is in the logic false condition while the low-voltage status signal is in the logic true condition, then performing only limited housekeeping operations while consuming but slight power, but if both the very-low-voltage and the low-voltage status signals are in the logic false condition, then performing functional operations, consuming during the course of so doing all such power as the performed operations require. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
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Specification