BUS NETWORK
A system according to various embodiments of the disclosure includes a bus and a plurality of devices coupled to the bus, the devices configured to communicate with each other via the bus. The system further includes a power supply coupled to the bus, the power supply for supplying power to the plurality of devices via the bus. The power supply is configured to detect an event, and in response to the event, alternately supply power to the plurality of devices via the bus at a first current level or at a second current level, the second current level less than the first current level. Among other things, embodiments in this disclosure help allow additional devices to be used on a bus, even where the total power consumption of the devices would normally exceed a maximum defined by a bus architecture. Furthermore, various embodiments help allow a single gauge of wire to be used throughout a bus network (even where long lengths of wire are required) while still providing sufficient power to the devices connected to the bus.
1 . A system comprising:
a bus;
a plurality of devices coupled to the bus, the devices configured to communicate with each other via the bus;
a power supply coupled to the bus, the power supply for supplying power to the plurality of devices via the bus, wherein the power supply is configured to:
detect an event; and
in response to the event, alternately supply power to the plurality of devices via the bus at a first current level or at a second current level, the second current level less than the first current level.
2 . The system of claim 1 , wherein the event includes a decrease in current drawn by the device, and the power supply is configured to supply power at the first current level in response to the detected decrease of the current drawn by the device.
3 . The system of claim 1 , wherein the event includes a decrease of an impedance for a device of the plurality of devices.
4 . The system of claim 3 , wherein the first current level exceeds a maximum threshold current level sustainable by the device when the device's impedance is decreased.
5 . The system of claim 3 , wherein the power supply is configured to supply power at the second current level in response to the detected decrease of the impedance for the device.
6 . The system of claim 1 , wherein the event includes an increase of an impedance for a device of the plurality of devices.
7 . The system of claim 6 , wherein the power supply is configured to supply power at the first current level in response to the detected increase of the impedance for the device.
8 . The system of claim 1 , wherein alternating between supplying power at the first current level and supplying power at the second current level includes decreasing a voltage for the power supplied at the second current level.
9 . The system of claim 1 , wherein alternating between supplying power at the second current level and supplying power at the first current level includes increasing a voltage for the power supplied at the first current level.
10 . The system of claim 1 , wherein the power supply is configured to gradually alternate between supplying power at the first current level and supplying power at the second current level.
11 . The system of claim 1 , wherein the power supply is configured to gradually alternate between supplying power at the second current level and supplying power at the first current level.
12 . The system of claim 1 , wherein the event includes an increase in current drawn by a device of the plurality of devices.
13 . The system of claim 12 , wherein the power supply is configured to supply power at the second current level in response to the detected increase in current drawn by the device.
14 . The system of claim 12 , wherein the power supply is configured to supply power at the second current level in response to a rate of the increase in current being drawn by the device.
15 . The system of claim 1 , wherein the event includes a decrease in current drawn by a device of the plurality of devices.
16 . The system of claim 15 , wherein the power supply is configured to supply power at the first current level in response to the detected decrease of the current drawn by the device.
17 . The system of claim 15 , wherein the power supply is configured to supply power at the first current level in response to a rate of the decrease in current being drawn by the device.
18 . The system of claim 1 , wherein the event includes a decrease in voltage output by the power supply.
19 . The system of claim 1 , wherein the event includes an increase in voltage output by the power supply.
20 . The system of claim 1 , wherein at least one of the plurality of devices includes an input stage comprising a rectifier and an energy storage device, wherein the energy storage device is charged by voltage from the power supply and the rectifier helps prevent discharge of the energy storage device through the bus.
21 . The system of claim 1 , wherein a device of the plurality of devices is configurable to control an amount of current drawn by the device.
22 . The system of claim 21 , wherein the current drawn by the device is determined by transmitting a command to the device via the bus.
23 . The system of claim 21 , wherein the amount of current drawn by the device is determined based on a current level of the power supplied by the power supply via the bus.
24 . The system of claim 21 , wherein the device is configured detect a communication associated with another of the plurality of devices, and the amount of current drawn by the device is determined based on detecting the communication.
25 . The system of claim 1 , further comprising a control device coupled to the bus, the control device configured to indicate to the power supply to supply power at the first current level or the second current level.
26 . The system of claim 25 , wherein the plurality of devices are configured to communicate asynchronously via the bus, and wherein the control device is further configured to arbitrate communication between the plurality of devices via the bus.
27 . The system of claim 1 , wherein the plurality of devices are configured to communicate synchronously via the bus.
28 . The system of claim 1 , wherein a device of the plurality of devices is configured to detect a communication associated with another of the plurality of devices.
29 . A system comprising:
a bus;
a plurality of devices coupled to the bus, the devices configured to communicate with each other via the bus;
a power supply coupled to the bus, the power supply for supplying power to the plurality of devices via the bus, wherein a device of the plurality of devices is configured to control an amount of current drawn by the device.