WO2016030370A1

WO2016030370A1 - Circuits with serially coupled supply inputs

Info

Publication number: WO2016030370A1
Application number: PCT/EP2015/069440
Authority: WO
Inventors: Matthias Wendt; Georg Sauerländer
Original assignee: Philips Lighting Holding B.V.
Priority date: 2014-08-27
Filing date: 2015-08-25
Publication date: 2016-03-03

Abstract

Devices comprise first and second circuits (1, 2) with first and second supply inputs. The first and second supply inputs are coupled serially to first supply outputs of power supplies (11). Third circuits (3) introduce compensation to amplitudes of first / second currents flowing through the first / second supply inputs. The first circuits (1) may comprise internal third circuits and may have different power consuming modes to realize said compensation. Fourth circuits (4) may monitor differences between amplitudes of the first currents and required amplitudes of the second currents and in response to monitoring results inform the first circuits (1). External third circuits (3) may comprise first and second arrangements (31-33, 34-36) coupled in parallel to the first and second supply inputs such as zener diodes (31, 34), capacitors (32, 35) and current sources (33, 36). Fourth circuits (4) may monitor differences between the amplitudes of the first and second currents and in response to monitoring results control the current sources (33, 36).

Description

CIRCUITS WITH SERIALLY COUPLED SUPPLY INPUTS

FIELD OF THE INVENTION

The invention relates to a device. Examples of such a device are consumer products and professional products. BACKGROUND OF THE INVENTION

US 2007 / 0202932 Al discloses a system for reducing standby power consumption. Thereto, a supply input of a switched mode power supply controller and a supply input of a receiver / decoder are coupled serially to a supply output of a mains supply. SUMMARY OF THE INVENTION

It is an object of the invention to provide an improved device. Thereto, a device is provided comprising

a first circuit comprising a first supply input and comprising at least one of a first information input and a first information output,

- a second circuit comprising a second supply input and comprising at least one of a second information input and a second information output, the first and second supply inputs being configured to be coupled serially to a first supply output of a power supply, and a third circuit for introducing compensation to at least one of an amplitude of a first current flowing through the first supply input and an amplitude of a second current flowing through the second supply input.

The first circuit such as for example a first information processing circuit comprises a first supply input for receiving first power from a power supply and comprises a first information input for receiving first information and/or a first information output for providing further first information. The second circuit such as for example a second information processing circuit comprises a second supply input for receiving second power from the power supply and comprises a second information input for receiving second information and/or a second information output for providing further second information. Just like in US 2007 / 0202932 Al, the first and second supply inputs are configured to be coupled serially to a first supply output of the power supply. In this prior art situation, the power supply comprises a voltage source with a serial resistor. This combination of the voltage source and the serial resistor functions as a current source. As a result, in the prior art situation, much power is wasted. To improve this prior art situation, the serial resistor is left out, and the device is provided with a third circuit for introducing compensation to at least one of an amplitude of a first current flowing through the first supply input and an amplitude of a second current flowing through the second supply input.

As a result, at least one of the amplitudes of the first and second currents flowing through the first and second supply inputs can get compensation. In case of the amplitudes of the first and second currents originally being substantially identical, no compensation needs to be provided. In case of the amplitudes of the first and second currents originally needing to be substantially different, compensation is provided. The first and second circuits can then guide currents having amplitudes that suit the first and second circuits, without so much power being wasted. This is a great improvement.

Two amplitudes are substantially identical if their values differ from each other by no more than a tolerance value. Two amplitudes are substantially different if their values differ from each other by more than a tolerance value. The third circuit may be an internal circuit situated within the first circuit or within the second circuit or may be an external circuit situated outside the first and second circuits. The power supply comprises a voltage source.

An embodiment of the device is defined by a first terminal of the first supply input being configured to be coupled to a first terminal of the first supply output, a second terminal of the first supply input being coupled to a first terminal of the second supply input, and a second terminal of the second supply input being configured to be coupled to a second terminal of the first supply output. Usually, the first and second supply inputs and the first supply output will each comprise two terminals.

An embodiment of the device is defined by the first circuit comprising the third circuit, the first circuit having different power consuming modes, the first circuit staying in a power consuming mode when the amplitude of the first current is substantially identical to a required amplitude of the second current and going into a lower power consuming mode when the amplitude of the first current is substantially larger than the required amplitude of the second current and going into a higher power consuming mode when the amplitude of the first current is substantially smaller than the required amplitude of the second current. This embodiment defines an internal third circuit that forms part of the first circuit. An example of such a first circuit is a controller chip. An example of such a third circuit is a microcontroller inside the controller chip. An example of a second circuit is a receiver, a transmitter or a transceiver having an off-mode, a standby-mode and an on-mode, whereby the power dissipation in the standby-mode may be quite different from the power dissipation in the on- mode.

Two amplitudes are substantially identical if their values differ from each other by no more than a tolerance value. An amplitude is substantially larger or substantially smaller than another amplitude if its value is larger or smaller by more than a tolerance value.

An embodiment of the device is defined by further comprising - a fourth circuit for monitoring a difference between the amplitude of the first current and the required amplitude of the second current and for in response to a monitoring result informing the first circuit.

A difference between the amplitude of the first current and the required amplitude of the second current can be monitored directly by determining both amplitudes of both currents and comparing them and can be monitored indirectly by for example determining an amplitude of a voltage present between the supply inputs and comparing it with a threshold value. In case the amplitude of the voltage is larger or smaller than the threshold value by more than a tolerance value, a power consuming mode is to be changed. A difference between the amplitude of the voltage and the threshold value represents a difference between said amplitudes of the first and second currents.

An embodiment of the device is defined by the third circuit comprising a first arrangement coupled in parallel to the first supply input. This embodiment defines an external third circuit that is situated outside the first and second circuits.

An embodiment of the device is defined by the first arrangement comprising a first zener diode and/or a first capacitor. A first zener diode may be coupled in parallel to the first supply input, to provide said compensation by allowing a first compensation current to flow in parallel to the first current. A first capacitor may be coupled in parallel to the first supply input, for storing power and/or for smoothing signals. A parallel connection of a first zener diode and a first capacitor may be coupled in parallel to the first supply input.

An embodiment of the device is defined by the first arrangement comprising a first current source. A first current source may be coupled in parallel to the first supply input, to provide said compensation by allowing a first compensation current to flow in parallel to the first current.

An embodiment of the device is defined by further comprising a fourth circuit for monitoring a difference between the amplitude of the first current and the amplitude of the second current and for in response to a monitoring result controlling the first current source.

A difference between the amplitude of the first current and the amplitude of the second current can be monitored directly by determining both amplitudes of both currents and comparing them and can be monitored indirectly by for example determining an amplitude of a voltage present between the supply inputs and comparing it with a threshold value. In case the amplitude of the voltage is larger or smaller than the threshold value by more than a tolerance value, the first current source needs to be controlled. In other words, then an amplitude of the first compensation current produced by the first current source is to be changed.

An embodiment of the device is defined by the third circuit further comprising a second arrangement coupled in parallel to the second supply input. Two arrangements will offer more control options than one arrangement.

An embodiment of the device is defined by the first arrangement comprising a first zener diode and/or a first capacitor and the second arrangement comprising a second zener diode and/or a second capacitor. A first (second) zener diode may be coupled in parallel to the first (second) supply input, to provide said compensation by allowing a first (second) compensation current to flow in parallel to the first (second) current. A first (second) capacitor may be coupled in parallel to the first (second) supply input, for storing power and/or for smoothing signals. A parallel connection of a first (second) zener diode and a first (second) capacitor may be coupled in parallel to the first (second) supply input.

An embodiment of the device is defined by the first arrangement comprising a first current source and the second arrangement comprising a second current source. A first (second) current source may be coupled in parallel to the first (second) supply input, to provide said compensation by allowing a first (second) compensation current to flow in parallel to the first (second) current.

An embodiment of the device is defined by further comprising a fourth circuit for monitoring a difference between the amplitude of the first current and the amplitude of the second current and for in response to a monitoring result controlling at least one of the first and second current sources.

Again, a difference between the amplitude of the first current and the amplitude of the second current can be monitored directly by determining both amplitudes of both currents and comparing them and can be monitored indirectly by for example determining an amplitude of a voltage present between the supply inputs and comparing it with a threshold value. In case the amplitude of the voltage is larger or smaller than the threshold value by more than a tolerance value, at least one of the first and second current sources needs to be controlled. In other words, then an amplitude of at least one of the first and second compensation currents produced by the first and second current sources is to be changed.

An embodiment of the device is defined by further comprising a fifth circuit for shifting a level of at least one of the first information input and the first information output and the second information input and the second information output.

In case the first (second) supply input of the first (second) circuit is connected to ground, the second (first) information input and the second (first) information output will not be at ground level and may need to be shifted in level to be at ground level. Alternatively, one or more information inputs and/or one or more information outputs can be shifted to one or more arbitrary levels.

An embodiment of the device is defined by further comprising the power supply further comprising a second supply output, and an interface comprising an interface input coupled to the second supply output. The power supply may have, in addition to the first supply output for feeding the first, second and third circuits, a second supply output for feeding an interface. Both supply outputs may be different supply outputs or may be the same supply output.

An embodiment of the device is defined by further comprising a load coupled to an interface output of the interface.

The load may for example be a light emitting diode circuit, and the interface may be a driver for driving the light emitting diode circuit. A light emitting diode circuit comprises one or more light emitting diodes of whatever kind and in whatever combination.

A basic idea is that, for serially fed circuits, current compensation is to be introduced. A problem to provide an improved device has been solved. A further advantage is that a power supply for serially feeding circuits can become simple and low cost and that it can provide currents having amplitudes that suit the first and second circuits without relatively much power being wasted and that it is no longer necessary to use separate relatively high-voltage and relatively low- voltage power supplies for feeding the interface / load and the first / second circuits respectively. These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

Fig . 1 shows an embodiment of a device,

Fig . 2 shows a first embodiment of circuits,

Fig . 3 shows a second embodiment of circuits,

Fig . 4 shows a third embodiment of circuits, and

Fig . 5 shows a fourth embodiment of circuits.

DETAILED DESCRIPTION OF EMBODIMENTS

In the Fig. 1, an embodiment of a device is shown. The device comprises a power supply 1 1 with a supply input coupled to a mains source 10 and with a first supply output coupled to serially connected first and second supply inputs of first and second circuits 1, 2. The power supply 1 1 comprises a second supply output coupled to an input of an interface 12 such as a driver. An output of the interface 12 is connected to a load 13 such as a light emitting diode circuit. The power supply 1 1 feeds a serial combination of the first and second circuits 1, 2 via the first supply output and feeds the interface 12 via the second supply output. Alternatively, this feeding may be done via one and the same supply output.

The first circuit 1 further comprises a first information input and/or a first information output, such as for example a first information in/output coupled to an information in/output of the interface 12. The second circuit 2 further comprises a second information input and/or a second information output, such as for example a second information in/output coupled to a second information in/output of the first circuit 1, and such as for example an antenna in/output coupled to an antenna for receiving and/or transmitting signals.

A third circuit introduces compensation to at least one of an amplitude of a first (DC) current flowing through the first supply input and an amplitude of a second (DC) current flowing through the second supply input. In the Fig. 1, this third circuit forms part of the first circuit 1 (internal solution). In that case, the first circuit 1 may have different power consuming modes. The first circuit 1 stays in a power consuming mode when the amplitude of the first current is substantially identical to a required amplitude of the second current and goes into a lower power consuming mode when the amplitude of the first current is substantially larger than the required amplitude of the second current and goes into a higher power consuming mode when the amplitude of the first current is substantially smaller than the required amplitude of the second current.

An example of such a first circuit 1 is a controller chip. An example of such a third circuit is a microcontroller inside the controller chip. An example of a second circuit 2 is a receiver, a transmitter or a transceiver having an off-mode, a standby-mode and an on- mode. The power dissipation in the standby-mode may be quite different from the power dissipation in the on-mode, and, for example in this case, said compensation is introduced advantageously.

A fourth circuit may monitor a difference between the amplitude of the first current and the required amplitude of the second current and may in response to a monitoring result inform the first circuit 1. In the Fig. 1, this fourth circuit may also form part of the first circuit 1.

A difference between the amplitude of the first current and the required amplitude of the second current can be monitored directly by determining both amplitudes of both currents and comparing them, but can also be monitored indirectly by for example determining an amplitude of a voltage present between the supply inputs and comparing it with a threshold value. In case the amplitude of the voltage is larger or smaller than the threshold value by more than a tolerance value, a power consuming mode is to be changed. A difference between the amplitude of the voltage and the threshold value represents a difference between said amplitudes of the first and second currents. In case the amplitude of the voltage present between the supply inputs gets too high, an amplitude of the first current is to be increased, to allow an amplitude of the second current to be increased too, and in case the amplitude of the voltage present between the supply inputs gets too low, an amplitude of the first current is to be decreased, to allow an amplitude of the second current to be decreased too.

Especially in case of the first circuit 1 being a controller chip and the second circuit 2 being a receiver, a transmitter or a transceiver controlled by the controller chip, the first circuit 1 knows what the second circuit 2 is doing and can increase / decrease an amplitude of its first current (by increasing / decreasing a processing speed or by increasing / decreasing an amount of non-operational code to be processed etc.) in response to an estimation of the required amplitude of the second current etc.

In the Fig. 2, a first embodiment of circuits is shown. The first and second circuits 1, 2 for example correspond with the ones shown in the Fig. 1. In addition, the third circuit 3 is shown. In the Fig. 2, this third circuit 3 does not form part of the first circuit 1 (external solution). This third circuit 3 may comprise a first arrangement 31-32 coupled in parallel to the first supply input. The first arrangement 31-32 comprises a first zener diode 31 to provide said compensation by allowing a first compensation current to flow through the first zener diode 31 in parallel to the first current and/or comprises a first capacitor 32 for storing power and/or for smoothing signals. This third circuit 3 may further comprise a second arrangement 34-35 coupled in parallel to the second supply input. The second arrangement 34-35 comprises a second zener diode 34 to provide said compensation by allowing a second compensation current to flow through the second zener diode 34 in parallel to the second current and/or comprises a second capacitor 35 for storing power and/or for smoothing signals.

In the Fig. 3, a second embodiment of circuits is shown. The second embodiment shown in the Fig. 3 differs from the first embodiment shown in the Fig. 2 in that the third circuit 3 here comprises a first arrangement 32-33 coupled in parallel to the first supply input. The first arrangement 32-33 comprises a first current source 33 to provide said compensation by allowing a first compensation current to flow through the first current source 33 in parallel to the first current and/or comprises a first capacitor 32 for storing power and/or for smoothing signals. The third circuit 3 here further comprises a second arrangement 35-36 coupled in parallel to the second supply input. The second arrangement 35-36 comprises a second current source 36 to provide said compensation by allowing a second compensation current to flow through the second current source 36 in parallel to the second current and/or comprises a second capacitor 35 for storing power and/or for smoothing signals.

A fourth circuit may monitor a difference between the amplitude of the first current and the amplitude of the second current and may in response to a monitoring result control at least one of the first and second current sources 33, 36. In the Fig. 3, this fourth circuit forms part of the first circuit 1.

A difference between the amplitude of the first current and the amplitude of the second current can be monitored directly by determining both amplitudes of both currents and comparing them and can be monitored indirectly by for example determining an amplitude of a voltage present between the supply inputs (read: between the capacitors 32 and 35) and comparing it with a threshold value. In case the amplitude of the voltage is larger or smaller than the threshold value by more than a tolerance value, at least one of the first and second current sources 33, 36 needs to be controlled. In other words, then an amplitude of at least one of first and second (DC) compensation currents produced by the first and second current sources 33, 36 is to be changed. In case the amplitude of the voltage present between the supply inputs gets too high, an amplitude of the second compensation current produced by the second current source 36 is to be decreased, and/or an amplitude of the first compensation current produced by the first current source 33 is to be increased. In case the amplitude of the voltage present between the supply inputs gets too low, an amplitude of the first compensation current produced by the first current source 33 is to be decreased, and/or an amplitude of the second compensation current produced by the second current source 36 is to be increased.

In the Fig. 4, a third embodiment of circuits is shown. The third embodiment shown in the Fig. 4 differs from the second embodiment shown in the Fig. 3 in that the fourth circuit 4 is located outside the first circuit 1 and inside the third circuit 3. But alternatively, the fourth circuit 4 may be located outside the third circuit 3.

In the Fig. 5, a fourth embodiment of circuits is shown. The fourth embodiment shown in the Fig. 5 differs from the third embodiment shown in the Fig. 4 in that the fourth circuit 4 has been left out, in that the power supply is here feeding three serially connected circuits 1, 2 and 6, and in that a fifth circuit 5 has been added.

The first supply input of the first circuit 1 is coupled to a first arrangement 32- 33 of a parallel connection of a first capacitor 32 and a first current source 33. The second supply input of the second circuit 2 is coupled to a second arrangement 35-36 of a parallel connection of a second capacitor 35 and a second current source 36. The further circuit 6 comprises a further supply input and comprises at least one of a further information input and a further information output. The further supply input of the further circuit 6 is coupled to a further arrangement 38-39 of a parallel connection of a further capacitor 38 and a further current source 39.

The fifth circuit 5 may shift a level of one or more of the information inputs and the information outputs of the circuits 1, 2 and 6. In case the first supply input of the first circuit 1 is connected to ground, the second and further information inputs and the second and further information outputs of the second and further circuits 2, 6 will not be at ground level and may need to be shifted in level to be at ground level etc. But alternatively, another one than the first supply input of the first circuit 1 may be connected to ground. Alternatively, all circuits 1, 2 and 6 may get some other level shift etc. In the Fig. 5, the fifth circuit 5 is located inside the third circuit 3. But alternatively, the fifth circuit 5 may be located outside the third circuit 3. Alternatively, the fifth circuit 5 may form part of one or more of the circuits 1, 2 and 6.

Other kinds of a first circuit 1 than a controller chip are possible too. Other kinds of a second circuit 2 than a receiver, a transmitter or a transceiver are possible too. Each circuit may be a separate chip or a part of a larger chip etc. First and second elements can be coupled indirectly via a third element and can be coupled directly without the third element being in between. Usually, each supply input and each supply output will consist of two terminals, whereby a first terminal of a first supply input is coupled to a first terminal of a first supply output, a second terminal of the first supply input is coupled to a first terminal of a second supply input, and a second terminal of the second supply input is coupled to a second terminal of the first supply output, to realize serial feeding. Instead of using capacitors connected in parallel to each supply input, each non-grounded terminal of the supply inputs may be connected via its own capacitor to ground.

Summarizing, devices comprise first and second circuits 1, 2 with first and second supply inputs. The first and second supply inputs are coupled serially to first supply outputs of power supplies 1 1. Third circuits 3 introduce compensation to amplitudes of first / second currents flowing through the first / second supply inputs. The first circuits 1 may comprise internal third circuits and may have different power consuming modes to realize said compensation. Fourth circuits 4 may monitor differences between amplitudes of the first currents and required amplitudes of the second currents and in response to monitoring results inform the first circuits 1. External third circuits 3 may comprise first and second

arrangements 31-33, 34-36 coupled in parallel to the first and second supply inputs such as zener diodes 31, 34, capacitors 32, 35 and current sources 33, 36. Fourth circuits 4 may monitor differences between the amplitudes of the first and second currents and in response to monitoring results control the current sources 33, 36.

While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

Claims

CLAIMS:

1. A device comprising

a first circuit (1) comprising a first supply input and comprising at least one of a first information input and a first information output,

a second circuit (2) comprising a second supply input and comprising at least one of a second information input and a second information output, the first and second supply inputs being configured to be coupled serially to a first supply output of a power supply (1 1), and

a third circuit (3) for introducing compensation to at least one of an amplitude of a first current flowing through the first supply input and an amplitude of a second current flowing through the second supply input.

2. The device as defined in claim 1, a first terminal of the first supply input being configured to be coupled to a first terminal of the first supply output, a second terminal of the first supply input being coupled to a first terminal of the second supply input, and a second terminal of the second supply input being configured to be coupled to a second terminal of the first supply output.

3. The device as defined in claim 1, the first circuit (1) comprising the third circuit (3), the first circuit (1) having different power consuming modes, the first circuit (1) staying in a power consuming mode when the amplitude of the first current is substantially identical to a required amplitude of the second current and going into a lower power consuming mode when the amplitude of the first current is substantially larger than the required amplitude of the second current and going into a higher power consuming mode when the amplitude of the first current is substantially smaller than the required amplitude of the second current.

4. The device as defined in claim 3, further comprising

a fourth circuit (4) for monitoring a difference between the amplitude of the first current and the required amplitude of the second current and for in response to a monitoring result informing the first circuit (1).

5. The device as defined in claim I, the third circuit (3) comprising a first arrangement (31 -33) coupled in parallel to the first supply input.

6. The device as defined in claim 5, the first arrangement (31-33) comprising a first zener diode (31) and/or a first capacitor (32).

7. The device as defined in claim 5, the first arrangement (31-33) comprising a first current source (33).

8. The device as defined in claim 7, further comprising

a fourth circuit (4) for monitoring a difference between the amplitude of the first current and the amplitude of the second current and for in response to a monitoring result controlling the first current source (33).

9. The device as defined in claim 5, the third circuit (3) further comprising a second arrangement (34-36) coupled in parallel to the second supply input.

10. The device as defined in claim 9, the first arrangement (31-33) comprising a first zener diode (31) and/or a first capacitor (32) and the second arrangement (34-36) comprising a second zener diode (34) and/or a second capacitor (35).

1 1. The device as defined in claim 9, the first arrangement (31-33) comprising a first current source (33) and the second arrangement (34-36) comprising a second current source (36).

12. The device as defined in claim 1 1, further comprising

- a fourth circuit (4) for monitoring a difference between the amplitude of the first current and the amplitude of the second current and for in response to a monitoring result controlling at least one of the first and second current sources (33, 36).

13. The device as defined in claim 1, further comprising

a fifth circuit (5) for shifting a level of at least one of the first information input and the first information output and the second information input and the second information output.

The device as defined in claim 1, further comprising

the power supply (1 1) further comprising a second supply output, and an interface (12) comprising an interface input coupled to the second supply

15. The device as defined in claim 14, further comprising

a load (13) coupled to an interface output of the interface (12).