Apparatus using serial data line to turn on a transceiver or other device
First Claim
Patent Images
1. An apparatus for conserving power in an electrical device, said apparatus comprising:
- a power supply switching circuit for providing a connection between a power supply and said electrical device, said power supply switching circuit having a signal input, a power input and a power output;
a startup circuit having an output connected to said signal input of said power supply switching circuit, said startup circuit generating a signal in response to transitions on a serial data transfer line, said signal being applied by said startup circuit to said signal input of said power supply switching circuit so as to switch on said power supply switching circuit;
a shutdown circuit, said shutdown circuit causing said startup circuit to switch off said power supply switching circuit in response to a shutdown signal; and
a keepalive circuit having an input connected to said power supply switching circuit, said keepalive circuit maintaining said power supply switching circuit in an on condition in the absence of said shutdown signal.
1 Assignment
0 Petitions
Accused Products
Abstract
An apparatus and a method for using a serial data line to turn on an electrical device are disclosed. Energy is extracted from a data signal on an asynchronous serial data line using a charge pump. The extracted energy is used by a power supply switching circuit to turn power on. Once turned on, power is kept on by a keepalive circuit. A shutdown signal causes the power to be turned off.
94 Citations
29 Claims
-
1. An apparatus for conserving power in an electrical device, said apparatus comprising:
-
a power supply switching circuit for providing a connection between a power supply and said electrical device, said power supply switching circuit having a signal input, a power input and a power output; a startup circuit having an output connected to said signal input of said power supply switching circuit, said startup circuit generating a signal in response to transitions on a serial data transfer line, said signal being applied by said startup circuit to said signal input of said power supply switching circuit so as to switch on said power supply switching circuit; a shutdown circuit, said shutdown circuit causing said startup circuit to switch off said power supply switching circuit in response to a shutdown signal; and a keepalive circuit having an input connected to said power supply switching circuit, said keepalive circuit maintaining said power supply switching circuit in an on condition in the absence of said shutdown signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-
15. A method for turning on an electrical device having a power supply and a power input for connection to said power supply, said electrical device receiving a data signal, said data signal comprising a plurality of transitions, said method comprising:
-
using said plurality of transitions in said data signal to generate a turn on signal; and using said turn on signal to connect said power supply to said power input thereby turning on said electrical device. - View Dependent Claims (16, 17, 18, 21, 22, 23)
-
- 19. A method of turning on a power supply comprising the step of extracting energy from transitions on an asynchronous serial data line.
-
25. An apparatus comprising:
-
a power supply switching circuit that provides a connection between a power supply and an electrical device; and a startup circuit connected to said power supply switching circuit, said startup circuit generating a turn on signal in response to a plurality of transitions on a serial data transfer line; wherein said turn on signal is applied to said power supply switching circuit, thereby causing said power supply switching circuit to provide said connection between said power supply and said electrical device. - View Dependent Claims (26, 27, 28, 29)
-
Specification