Energy-saving power adapter/charger
A power device for an electronic device, such as a charger for a portable rechargeable device and/or an AC adapter. The power device includes switching circuitry for de-powering at least a portion of the power device.
1. A power device for supplying power to an electronic device, the power device comprising:
an input for receiving electrical input power from a source, the input power having an input voltage;
an output for delivering electrical output power to the electronic device, the output power having an output voltage;
power circuitry for converting the input voltage to the output voltage; and
a latching relay coupled between the input and the power circuitry, wherein the latching relay is closed to change the power circuitry to the “on” state and opened to change the power circuitry to the “off” state,
wherein the output voltage is substantially constant when the power circuitry is in the “on” state.
2. The power device as recited in claim 1 , further comprising a transformer and a load sensing portion operable to sense one or more pulses from the transformer and determine the power or load being drawn from the power device by the electronic device based thereon.
3. The power device as recited in claim 2 , wherein the load sensing device is incorporated within an integrated circuit.
4. The power device as recited in claim 2 , wherein the load sensing portion is operable to cause the latching relay to change the power circuitry to the “off” state after determining that the load being drawn from the power device by the electronic device has been below a threshold lever for a predetermined amount of time.
5. The power device as recited in claim 1 further comprising:
a first portion comprising the input and a first housing; and
a second portion comprising:
the output;
a connector for electrically coupling with the electronic device; and
two or more electrical terminals which, when connected, are configured to cause the power circuitry to switch to the “on” state, and
wherein the power device further comprises a cable electrically coupling the first portion with the second portion.
6. The power device as recited in claim 5 , wherein the two or more terminals are connected by a switch.
7. The power device as recited in claim 1 , wherein the power circuitry comprises an AC portion and a DC portion, and wherein the latching relay is operable to de-power the AC portion of the power circuitry when the latching relay is opened.
8. The power device as recited in claim 1 , further comprising a microcontroller for at least partially controlling the switching of the latching relay.
9. The power device as recited in claim 1 , wherein the latching relay is coupled between the input and the transformer.
10. A power device for supplying power to an electronic device, the power device comprising:
an input for receiving electrical input power from a source, the input power having an input voltage;
an output for delivering electrical output power to the electronic device, the output power having an output voltage;
power circuitry for converting the input voltage to the output voltage; and
a latching relay coupled between the input and the power circuitry, wherein the latching relay is closed in response to a remote electrical connection to change the power circuitry to the “on” state.
11. The power device as recited in claim 10 , wherein the latching relay is opened to change the power circuitry to the “off” state and the power device draws substantially no power from the source when the latching relay is open.
12. The power device as recited in claim 10 , wherein the remote electrical connection is established by a switch.
13. The power device as recited in claim 1 , wherein the latching relay closes in response to a remote electrical connection.
14. The power device as recited in claim 13 , wherein the remote electrical connection is established between the two or more terminals.
15. The power device as recited in claim 14 , wherein the remote electrical connection between the two or more terminals is established by a switch.
16. The power device as recited in claim 15 , wherein the switch is human-actuatable.
17. A power device for supplying power to an electronic device, the power device comprising:
an input for receiving electrical, input power from a source, the input power having an AC input voltage;
an output for delivering electrical output power to the electronic device, the output power having a DC output voltage;
power circuitry for converting the input voltage to the output voltage, the power circuitry including a transformer;
a latching relay coupled between the input and the transformer; and
control circuitry for causing the latching relay to close in response to a remote electrical connection established between two or more terminals to change the power circuitry to the “on” state and for causing the latching relay to open to change the power circuitry to the “off” state,
wherein the output voltage is substantially constant when the power circuitry is in the “on” state.
18. The power device as recited in claim 17 , wherein the remote electrical connection between the two or more terminals is established by a switch.
19. The power device as recited in claim 18 , wherein the switch is human-actuatable.
20. The power device as recited in claim 17 , wherein the power device draws substantially no power from the source when the power circuitry is in the “off” state.