Abstract: One example discloses a power management circuit, including: an ultrasonic transmitter configured to generate an ultrasonic signal having a set of transmitted ultrasonic signal attributes; an ultrasonic receiver configured to detect the ultrasonic signal having a set of received ultrasonic signal attributes; wherein the power management circuit is configured to cause a device to be operated at a first power level and a second power level; and a proximity detection circuit configured to transition the device from the first power level to the second power level in response to a preselected difference between the transmitted set of ultrasonic signal attributes and the received set of ultrasonic signal attributes.

Abstract: One example discloses a power management circuit, including: an ultrasonic transmitter configured to generate an ultrasonic signal having a set of transmitted ultrasonic signal attributes; an ultrasonic receiver configured to detect the ultrasonic signal having a set of received ultrasonic signal attributes; wherein the power management circuit is configured to cause a device to be operated at a first power level and a second power level; and a proximity detection circuit configured to transition the device from the first power level to the second power level in response to a preselected difference between the transmitted set of ultrasonic signal attributes and the received set of ultrasonic signal attributes.

Abstract: One example discloses a power management circuit, wherein the power management circuit is configured to cause a device to be operated at a first power level and a second power level. The circuit includes: an RF transmitter configured to generate an RF signal having a set of transmitted RF signal attributes; an RF receiver configured to detect the RF signal having a set of received RF signal attributes; and a proximity detection circuit configured to transition the device from the first power level to the second power level in response to a preselected difference between the transmitted set of RF signal attributes and the received set of RF signal attributes.

Abstract: One example discloses a power management circuit, wherein the power management circuit is configured to cause a device to be operated at a first power level and a second power level. The circuit includes: an RF transmitter configured to generate an RF signal having a set of transmitted RF signal attributes; an RF receiver configured to detect the RF signal having a set of received RF signal attributes; and a proximity detection circuit configured to transition the device from the first power level to the second power level in response to a preselected difference between the transmitted set of RF signal attributes and the received set of RF signal attributes.

Abstract: Disclosed is a power converter including a generator configured to generate a sequence of output voltage waveforms, a resonant tank connected to the generator comprising at least one capacitor and at least one inductor, a transformer including a primary side connected in series with said series inductor and, the primary side being configurable to use at least one primary winding tap and a secondary side for connecting to a rectifying circuit for providing a rectified DC voltage to an output load circuit, a first switch and a second switch on the primary side connected to the primary winding, wherein the at least one primary winding is selected by the first switch or the second switch to select a different reflected output voltage by closing the first switch or the second switch.

Abstract: Disclosed is a power converter including a generator configured to generate a sequence of output voltage waveforms, a resonant tank connected to the generator comprising at least one capacitor and at least one inductor, a transformer including a primary side connected in series with said series inductor and, the primary side being configurable to use at least one primary winding tap and a secondary side for connecting to a rectifying circuit for providing a rectified DC voltage to an output load circuit, a first switch and a second switch on the primary side connected to the primary winding, wherein the at least one primary winding is selected by the first switch or the second switch to select a different reflected output voltage by closing the first switch or the second switch.

Abstract: A method for an up-down converter which is based on a buck converter during the current down-conversion phase (?2, ?3 and ?5, ?6, respectively) of the coil (L1) supplies an output (B) with a relatively high output voltage (UB), where UB>Uin. The down-conversion phase of the coil current (IL1) comprises at least two different down-conversion phases (?2, ?3 and ?5, ?6, respectively). A method for an up-down converter, which converter is based on a boost converter, supplies during the current up-conversion phase (?7, and ?10, respectively) of the coil (L2) an output (D) which has a relatively low output voltage (UD) with power, where UD>Uin. The up-conversion phase of the coil current (IL2) comprises at least two different current reduction phases (?7, ?8 and ?10, ?11, respectively).

Abstract: The multiple-output DC-DC converter comprises an inductor (L) and a main switch (S0) which periodically couples a DC-input voltage (Vin) to the inductor (L). Each one of a multitude of loads (L1, L2, L3) is coupled to the inductor (L) via one of a multitude of output switches (S1, S2, S3). One of a multitude of output voltages (V1, V2, V3) is present across each of the loads (L1, L2, L3). A controller (CO) controls the main switch (S0) and the output switches (S1, S2, S3) in sequences (SE) of cycles (CY). Each one of the cycles (CY1, CY2, CY3) contains an on-phase of the main switch (S0) followed by an on-phase of one of the multitude of output switches (S1, S2, S3). The cycles (CY1, CY2, CY3) have either a predetermined first (minimum) duty cycle (D1) or a second (maximum) duty cycle (D2) which is larger than the first duty cycle (D1).

Abstract: An identification transponder for transferring an identification code to a base station by varying an RF-signal transmitted by the base station in a rhythm which corresponds to the identification code. The identification transponder comprises an identification code generator, a rectifier; and a load transistor. The load transistor is arranged in such a manner that it performs two tasks: the task of rectifying the RF-signal to provide the DC supply voltage for the transponder, and the task of supplying a variable load to the rectifier to thereby vary the RF-signal transmitted by the base station.

Abstract: The present invention provides an n-phase integrated buck converter. The converter comprises a controller and a plurality of circuits each operably connected to the controller. The controller controls the plurality of circuits to respectively output a plurality of current signals each having an associated phase and generate an output voltage signal. By applying the n phase concept of the invention, the amount of current each phase (i.e., each of the plurality of circuits) has to deliver is reduced. This directly reduces the conduction losses in each phase. Because the current in each phase is lower, a smaller MOSFET in each of the plurality of circuits may be used. The smaller MOSFET is easier to switch. Therefore, the switching losses per phase are also reduced. Reducing these losses will enable the invention to achieve high efficiencies. Integration allows all of the components to become physically closer and capable of being switched faster.

Abstract: A DC/DC up/down converter (30), comprising inductive energy storage means (L), switching means (S1, S2, S3) and control means (40). The control means (40) are arranged for operatively controlling the switching means (S1, S2, S3) for transferring electrical energy to a first output (Vout1) of the DC/DC converter (30) in a down-conversion mode and for transferring electrical energy from the first output (Vout1) to a second output (Vout2) of the DC/DC converter (30) in an up-conversion mode.

Abstract: A DC/DC converter (1), comprising inductive electrical energy storage means (L), switching means (S1, S2) and control means (6). The control means (6) are arranged for selectively operating the switching means (S1, S2) for transferring an amount of electrical energy from the energy storage means (L) to an output of the DC/DC converter (1), for providing a desired output voltage (Vout), in accordance with a two-state switching cycle comprising a minimum and a maximum duty cycle (Dmin, Dmax).

Abstract: A multi-output DC/DC converter (1;10;30;40;50;60), comprising inductive electrical energy storage means (L), switching means (S0-S7) and control means (6;9;31;41;51;61). The control means (6;9;31;41;51;61) are arranged for selectively operating the switching means (S0-S7) for transferring an amount of electrical energy from the energy storage means (L) to an output (A;B;C;D) of the DC/DC converter (1;10;30;40;50;60) providing an output voltage in accordance with a switching sequence based on comparing, by the control means (6;9;31;41;51;61) of the output voltage of each output (A;B;C;D) with an associated reference voltage.

Abstract: The present invention provides an n-phase integrated buck converter. The converter comprises a controller and a plurality of circuits each operably connected to the controller. The controller controls the plurality of circuits to respectively output a plurality of current signals each having an associated phase and generate an output voltage signal. By applying the n phase concept of the invention, the amount of current each phase (i.e., each of the plurality of circuits) has to deliver is reduced. This directly reduces the conduction losses in each phase. Because the current in each phase is lower, a smaller MOSFET in each of the plurality of circuits may be used. The smaller MOSFET is easier to switch. Therefore, the switching losses per phase are also reduced. Reducing these losses will enable the invention to achieve high efficiencies. Integration allows all of the components to become physically closer and capable of being switched faster.

Abstract: A DC/DC converter (1; 20), comprising inductive electrical energy storage means (L), switching means (S1-S4) and means (6; 15) wherein said control means (6; 15) are arranged for selectively operating said switching means (S1-S4) for transferring an amount of electrical energy from said energy storage means (L) to an output of said DC/DC converter (1; 20), for providing a desired output voltage (Vout), characterized by digital control means (6; 15) which are configured for operatively controlling said switching means (S1-S4) for transferring electrical energy in accordance with a switching sequence comprising a ramp-up switching cycle and a ramp-down cycle for substantially charging and decharging of the energy storage means (L).

Abstract: A DC/DC up/down converter (30), comprising inductive energy storage means (L), switching means (S1, S2, S3) and control means (40). The control means (40) are arranged for operatively controlling the switching means (S1, S2, S3) for transferring electrical energy to a first output (Vout1) of the DC/DC converter (30) in a down-conversion mode and for transferring electrical energy from the first output (Vout1) to a second output (Vout2) of the DC/DC converter (30) in an up-conversion mode.

Abstract: A DC/DC converter (1), comprising inductive electrical energy storage means (L), switching means (S1, S2) and control means (6).

Abstract: A DC/DC converter (10; 30; 40; 50; 60), comprising inductive energy storage means (2), switching means (S0-S7) and control means (9; 31; 41; 51; 61), wherein said control means (9; 31; 41; 51; 61) are arranged for selectively operating said switching means (S0-S7) for providing electrical energy from said energy storage means (2) to an output (A; B; C; D) of said DC/DC converter (10; 30; 40; 50; 60) in both a Pulse Width Modulation (PWM) mode and a Pulse Frequency Modulation (PFM) mode switching cycle.

Abstract: A DC/DC converter (1; 20), comprising inductive electrical energy storage means (L), switching means (S1-S4) and means (6; 15) wherein said control means (6; 15) are arranged for selectively operating said switching means (S1-S4) for transferring an amount of electrical energy from said energy storage means (L) to an output of said DC/DC converter (1; 20), for providing a desired output voltage (Vout), characterized by digital control means (6; 15) which are configured for operatively controlling said switching means (S1-S4) for transferring electrical energy in accordance with a switching sequence comprising a ramp-up switching cycle and a ramp-down cycle for substantially charging and decharging of the energy storage means (L).

Abstract: A multi-output DC/DC converter (1; 10; 30; 40; 50; 60), comprising inductive electrical energy storage means (L), switching means (S0-S7) and control means (6; 9; 31; 41; 51; 61). The control means (6; 9; 31; 41; 51; 61) are arranged for selectively operating the switching means (S0-S7) for transferring an amount of electrical energy from the energy storage means (L) to an output (A; B; C; D) of the DC/DC converter (1; 10; 30; 40; 50; 60) providing an output voltage in accordance with a switching sequence based on comparing, by the control means (6; 9; 31; 41; 51; 61) of the output voltage of each output (A; B; C; D) with an associated reference voltage.