Back to results
US 8,264,194 B1Granted
Power control for a low power display
AssigneeGoogle Inc.
InventorsAaron Spangler, Matthew Wilson
Life of this patent
Estimating the term…
Abstract
A low power display device including a power control circuit for controlling power from an environmental energy source to a power storage device that is charged by the environmental energy source, is described.
Claims24
A method, comprising:
- periodically sampling, by a processing circuit, a voltage of a power storage device;
- determining, by the processing circuit and at a first time, that the voltage is less than a turn on voltage;
- and
- in response to determining that the voltage is less than the turn on voltage;
- causing the power storage device to enter a charging state, the power storage device being charged by an environmental energy source while in the charging state;
- periodically sampling the voltage of the power storage device while the power storage device is in the charging state, the periodic sampling having a first sampling period that is less than an amount of time required for the voltage of the power storage device to increase from a turn off voltage to a maximum rated voltage of the power storage device, the turn off voltage being a voltage at which the power storage device is transitioned out of the charging state;
- and
- while in the charging state, causing the processing circuit to transition to a low power state between each periodic sample of the voltage.
5 more elements
A power control circuit, comprising:
- a capacitor;
- and
- a processing circuit configured to:
- periodically sample a voltage across the capacitor;
- determine, at a first time, that the voltage across the capacitor is greater than a turn off voltage;
- and
- in response to determining that the voltage is greater than the turn off voltage:
- cause the capacitor to transition to a discharging state;
- periodically sample the voltage across the capacitor while the capacitor is in the discharging state, the periodic sampling having a first a sampling period that is less than an amount of time required for the capacitor to discharge from a turn on voltage to a minimum input voltage, the minimum input voltage being a voltage required for operation of a power supply drawing power from the capacitor, the turn on voltage being a voltage at which the capacitor is transitioned to a charging state;
- and
- while the capacitor is in the discharging state, transition to a low power state between each periodic sample of the voltage across the capacitor.
8 more elements
A power control circuit, comprising:
- a capacitor;
- and
- a processing circuit configured to:
- periodically sample a voltage across the capacitor;
- determine, at a first time, that the voltage across the capacitor is less than a turn on voltage;
- and
- in response to determining that the voltage across the capacitor is less than the turn on voltage:
- cause the capacitor to transition to a charging state, the capacitor being charged by an environmental energy source while in the charging state;
- periodically sample the voltage across the capacitor while the capacitor is in the charging state, the periodic sampling having a first a sampling period that less than an amount of time required for current from the environmental energy source to charge the capacitor from a turn off voltage to a rated voltage capacity of the capacitor, the turn off voltage being a voltage at which the capacitor is transitioned out of the charging state;
- and
- while the capacitor is in the charging state, transition to a low power state between each periodic sample of the voltage across the capacitor.
8 more elements
Dependencies are inferred from the claim text.