JP5597145B2 - Power transmission equipment - Google Patents

Description

  The present invention relates to a power transmission device, and more particularly to a non-contact power transmission device using a resonator between transmission and reception.

  In wireless power transmission using a magnetic resonance provided with a resonator between transmission and reception, power is transmitted between two coils using an LC resonator. In this case, by making the Q value of the resonator very high, there is almost no copper loss or iron loss, and the loss of energy related to transmission can be reduced. Therefore, energy can be transmitted with high power efficiency even between coils having a low coupling coefficient (see Patent Document 1).

JP-A-9-261898

  The following analysis is given in the present invention.

  Since a power transmission device using an LC resonator uses a resonance circuit having a high Q value, power is transmitted only in a narrow resonance frequency band. Therefore, when the resonance frequency of the transmission / reception coil does not match accurately, or when the drive frequency of the transmission coil and the resonance frequency of the transmission coil do not match, the transmission efficiency decreases. That is, if the value of the inductor (coil) or capacitor constituting the resonator deviates from the initial design value due to a change or variation in the value of the inductor, the transmission efficiency is lowered.

  Therefore, an object of the present invention is to prevent a decrease in transmission efficiency when the resonance frequency of the resonator is shifted.

  The present inventor considered that a technique for matching the drive frequency of the circuit for driving the coil with the resonance frequency of the coil, or a technique for widening the frequency band so that power can be transmitted with high efficiency, was reached, leading to the present invention. .

Power transmission device according to a first aspect of the present invention, feed comprises a resonator between a signal circuit and the receiving circuit, the transmission circuit has an oscillator, the receiving circuit power from the oscillator In the non-contact type power transmission device for transmitting to the transmitter, the oscillator further includes a transmitter circuit- side resonator configured by connecting an inductor and a capacitor in series, and the transmitter circuit outputs a reference timing signal from the oscillator as an output node the through, and outputs it to the transmitting circuit side resonators, and output during the desired period of time, and drive the dynamic circuit you said output node to a high impedance during the desired period of time, from the transmitting circuit side resonator a phase comparator for comparing the phase of the reference timing signal of the signal, the-out based on the comparison result of the phase comparator, changing the frequency of said oscillator, co of the transmitting circuit side resonator And a control circuit for matching the frequency of said oscillator, to the transmitting circuit side.
A power transmission device according to another aspect of the present invention includes a resonator between a transmission circuit and a reception circuit, the transmission circuit includes an oscillator, and transmits power from the oscillator to the reception circuit. In the non-contact type power transmission device, the oscillator further includes a transmission circuit side resonator configured by connecting an inductor and a capacitor in series, and the transmission circuit receives a reference timing signal from the oscillator as an output node. And a phase of a signal output from the transmission circuit side resonator during the desired period, and a drive circuit that sets the output node to high impedance during the desired period. And a phase comparator that compares the phases of the reference timing signal and a comparison result of the phase comparator, and changes the value of the capacitor of the resonator on the transmission circuit side to And a control circuit for matching the frequency of the oscillator and the resonant frequency of the circuit-side resonator, to the transmitting circuit side.

を満足するαを、０．００１≦α≦０．０５、βを、０．９≦β≦１．１の範囲になるように定める。 Another power transmission device according to the aspect of the present invention includes, feeding comprises a resonator between a signal circuit and the receiving circuit, the transmission circuit has an oscillator, the receiving circuit power from the oscillator In the non-contact type power transmission device for transmitting to the transmitter, the transmitter further includes a transmission circuit side resonator configured by connecting a first inductor and a first capacitor in series, and a reference timing signal from the oscillator is output via an output node, It is output to the transmitting circuit side resonator, and is configured by a series connection of a drive circuit having a high impedance at the output node for a desired period, and a second inductor, a second capacitor, and a third capacitor A receiving circuit side resonator and a load resistor connected in parallel to the third capacitor, and the values of the first and second inductors are L ₁ and L ₂ , respectively, and the first, second and third Ki The value of Pashita was a C _1, C _2, C _p, respectively, when the resonance frequency of the transmitting circuit side and receiving circuit side resonance circuit and omega / 2 [pi,

Α satisfying the above is determined in a range of 0.001 ≦ α ≦ 0.05, and β in a range of 0.9 ≦ β ≦ 1.1.

  According to the present invention, it is possible to prevent a decrease in transmission efficiency even when the resonance frequency of the resonator is shifted.

It is a block diagram which shows the structure of the power transmission apparatus which concerns on 1st Example of this invention. It is a timing chart showing operation | movement of the electric power transmission apparatus which concerns on 1st Example of this invention. It is a figure which shows the deviation | shift between an output signal and a timing signal. It is a block diagram which shows the structure of the power transmission apparatus which concerns on 2nd Example of this invention. It is a timing chart showing operation | movement of the electric power transmission apparatus which concerns on 2nd Example of this invention. It is an equivalent circuit diagram which shows the principle of a structure of the power transmission apparatus which concerns on 3rd Example of this invention. It is a figure explaining the difference in the load voltage of a prior art and a 3rd Example. It is a figure which shows the power transmission efficiency of the past and the 3rd Example. It is a figure which shows the example of application of the power transmission apparatus of this invention. 1 is a configuration example of a semiconductor integrated circuit equipped with a wireless power transmission / reception circuit. It is a figure which shows the structural example of the power transmission apparatus which also communicates data by modulating the carrier of the electric power which transmits / receives. It is a figure which shows the example which performs data transmission / reception using frequency modulation. It is a figure which shows the example which performs data transmission / reception using amplitude modulation. It is a figure which shows the example which comprised SiP.

  Hereinafter, an embodiment for carrying out the present invention will be outlined. Note that the reference numerals of the drawings attached to the following outline are only examples for facilitating understanding, and are not intended to be limited to the illustrated embodiments.

A power transmission device according to an embodiment of the present invention is a non-contact power transmission device using a resonator between transmission and reception, and is configured by connecting an inductor (L1 in FIG. 1) and a capacitor (C1 in FIG. 1) in series. A transmission circuit side resonator to be driven, a drive circuit (Mn, Mp in FIG. 1) for driving one end of the transmission circuit side resonator in accordance with the reference timing signal and providing an output with high impedance, and a drive stop period In FIG. 1, a phase comparator (12 in FIG. 1) that compares the phase of the signal at one end of the transmitting circuit side resonator and the reference timing signal, and a control circuit (in FIG. 1) that matches the phases based on the comparison result in the phase comparator. 13, 14, 11) are provided on the transmission circuit side.

  The control circuit may change the phase of the reference timing signal based on the comparison result.

  The control circuit may change the value of the capacitor based on the comparison result.

  The drive circuit may be constituted by a CMOS circuit, and a time during which one and the other transistors of the CMOS circuit are simultaneously turned off may be set, and this time may be set as a drive stop period.

The drive circuit may be configured to set a predetermined period before and after the point when the drive current for driving one end of the transmission circuit side resonator crosses the 0 level to be in the OFF state.

  The drive circuit may set the time for which it is intermittently turned off.

を満足するαを、０．００１≦α≦０．０５、βを、０．９≦β≦１．１の範囲になるように定める。 A power transmission device according to another embodiment of the present invention includes a first inductor (L1 in FIG. 6) and a first capacitor (in FIG. 6) in a contactless power transmission device using a resonator between transmission and reception. C1) a series connection of the transmission circuit side resonator, a drive circuit (V1 in FIG. 6) for driving one end of the transmission circuit side resonator, a second inductor (L2 in FIG. 6), and a second A resonator on the receiving circuit side constituted by a series connection of a capacitor (C2 in FIG. 6) and a third capacitor (Cp in FIG. 6), and a load resistor (RL in FIG. 6) connected in parallel to the third capacitor When provided with the value of the first and second inductors are _L 1, _{L 2} respectively, and first, _C 1 the value of the second and third capacitors _{respectively,} C 2, _{C p,} transmitting circuit side And when the resonance frequency of the resonance circuit on the receiving circuit side is ω / 2π,

Α satisfying the above is determined in a range of 0.001 ≦ α ≦ 0.05, and β in a range of 0.9 ≦ β ≦ 1.1.

The signal that drives one end of the transmission circuit- side resonator in the power transmission device may be a signal modulated by a data signal.

  A voltage-controlled oscillator that frequency-modulates or phase-modulates the reference timing signal with a data signal may be provided.

A modulator that amplitude-modulates the output signal of the drive circuit with a data signal may be provided between the drive circuit and one end of the transmission circuit side resonator.

  A semiconductor integrated circuit device may include the above power transmission device.

  According to the power transmission device as described above, it is possible to prevent a decrease in transmission efficiency even when the resonance frequency of the resonator is shifted.

  Hereinafter, it will be described in detail with reference to the drawings in accordance with embodiments.

  FIG. 1 is a block diagram illustrating a configuration of a power transmission device according to a first embodiment of the present invention. In FIG. 1, the power transmission device includes a timing generation circuit 11, a phase comparator 12, a phase difference voltage conversion circuit 13, a voltage controlled oscillator 14, an NMOS transistor Mn, a PMOS transistor Mp, diodes D1 and D2, capacitors C1 and C2, and an inductor. L1 and L2 are provided.

  The timing generation circuit 11 receives an oscillation signal output from the voltage controlled oscillator 14, outputs a phase comparison enable signal EN, a timing signal (clock signal) Vr to the phase comparator 12, and supplies drive signals Vn and Vp to the NMOS transistor Mn. , Output to the respective gates of the PMOS transistor Mp.

  The NMOS transistor Mn has a drain connected to one end of the capacitor C1, and a source grounded. The PMOS transistor Mp has a drain connected to one end of the capacitor C1, and a source connected to the power supply. The diode D1 has a cathode connected to the drain of the NMOS transistor Mn and an anode connected to the source of the NMOS transistor Mn. The diode D2 has a cathode connected to the power supply and an anode connected to the drain of the NMOS transistor Mn.

The other end of the capacitor C1 is grounded via the inductor L1, and constitutes the inductor L1 and the transmission circuit side LC resonator.

The inductor L2 that is inductively coupled with the inductor L1 has one end grounded and the other end connected to a receiving circuit (not shown) via the capacitor C2, thereby forming a capacitor C2 and a receiving circuit side LC resonator.

  The phase comparator 12 compares the phase of the timing signal Vr and the signal Vc at one end of the capacitor C1 and outputs the phase difference to the phase difference voltage conversion circuit 13 when the phase comparison permission signal EN is at H level, for example. .

  The phase difference voltage conversion circuit 13 is composed of, for example, a charge pump or a ΔΣ modulator, generates a voltage corresponding to the phase difference output from the phase comparator 12, and outputs the voltage to the voltage controlled oscillator 14.

  The voltage controlled oscillator 14 generates an oscillation signal having an oscillation frequency that is changed according to the voltage output from the phase difference voltage conversion circuit 13.

Next, the operation of the power transmission apparatus according to this embodiment will be described. FIG. 2 is a timing chart showing the operation of the power transmission apparatus according to the first embodiment of the present invention. In the period T1, the timing generation circuit 11 sets the drive signals Vn and Vp to L level, the NMOS transistor Mn is turned off, and the PMOS transistor Mp is turned on. Therefore, the signal Vc at the drain of the NMOS transistor Mn becomes the power supply voltage, and the current Ic flows from the power supply into the transmission circuit side LC resonator.

In the period T3, the timing generation circuit 11 sets the drive signals Vn and Vp to H level, the NMOS transistor Mn is turned on, and the PMOS transistor Mp is turned off. Accordingly, the signal Vc becomes the ground voltage, and the current Ic flows from the transmission circuit side LC resonator toward the ground.

  In the periods T2 and T4, the timing generation circuit 11 sets the drive signals Vp and Vn to the H level and the L level, respectively, and turns off both the NMOS transistor Mn and the PMOS transistor Mp. Further, the phase comparison enable signal EN is set to the H level. Periods T2 and T4 are periods in which the output of the drive circuit is in a high impedance state, and the LC resonator continues to oscillate in a sine wave form, and the output signal Vc is determined by the current Ic flowing through the LC resonator. That is, in the first half of the period T2 and the second half of the period T4, the current Ic flows from the ground to the LC resonator via the diode D1. Therefore, the output signal Vc becomes a potential that is lower than the ground potential by the forward voltage drop VF of the diode D1. In the second half of the period T2 and the first half of the period T4, the current Ic flows from the LC resonator toward the power supply via the diode D2. Therefore, the output signal Vc becomes a potential that is higher than the power supply potential by the forward voltage drop VF of the diode D2.

  The phase comparator 12 compares the edges of the output signal Vc and the timing signal Vr sent from the timing generation circuit when the phase comparison permission signal EN is at the H level, that is, a signal flowing through the LC resonator. And the phase of the reference clock signal input to the timing generation circuit 11 are compared. 3A shows a waveform when the timing signal Vr is advanced, and FIG. 3B shows a waveform when the timing signal Vr is delayed.

  The phase difference voltage conversion circuit 13 receives the phase comparison result output from the phase comparator 12 and advances or delays the phase of the reference clock signal depending on which of the output signal Vc and the timing signal Vr is delayed or advanced. The frequency / phase of the resonance circuit and the frequency / phase of the drive circuit are matched.

According to the power transmission device as described above, with respect to the frequency of the drive signal of the transmission circuit side LC resonator, even when the shift resonance frequency of the transmitting circuit side LC resonator, the transmitting circuit side LC resonator by delaying or advancing the phase of the drive signal, it is matched with the resonance frequency of the frequency and the transmitting circuit side LC resonators of the drive signal transmitting circuit side LC resonators, it is possible to prevent a decrease in power transmission efficiency.

  FIG. 4 is a block diagram showing the configuration of the power transmission apparatus according to the second embodiment of the present invention. In FIG. 4, the same reference numerals as those in FIG. The power transmission device of this embodiment includes an oscillator 14a that oscillates at a constant frequency instead of the voltage controlled oscillator 14 of FIG. 1, and includes a variable capacitor C1a instead of the capacitor C1. The phase difference voltage conversion circuit 13 outputs a voltage corresponding to the phase difference signal output from the phase comparator 12 to the variable capacitor C1a, and the variable capacitor C1a changes its own capacitance value. Therefore, the resonance frequency by the variable capacitor C1a and the inductor L1 increases or decreases according to the phase difference signal.

  Next, the operation of the power transmission apparatus according to this embodiment will be described. FIG. 5 is a timing chart showing the operation of the power transmission apparatus according to the second embodiment of the present invention. The power transmission apparatus operates in the periods T1 and T3 in the same manner as the periods T1 and T3 described in the first embodiment.

  In the period T5, the timing generation circuit 11 sets the drive signals Vp and Vn to the H level and the L level, respectively, and turns off both the NMOS transistor Mn and the PMOS transistor Mp. Further, the phase comparison enable signal EN is set to the H level. The period T5 is a period in which the driving circuit is in a high impedance state, and the LC resonator continues to vibrate in a sine wave shape, and the output signal Vc of the driving circuit is determined by the current Ic flowing through the LC resonator. That is, when the current Ic flows from the ground to the LC resonator via the diode D1, the output signal Vc becomes a potential that is lower than the ground potential by the forward voltage drop VF of the diode D1. When the current Ic flows from the LC resonator toward the power supply via the diode D2, the output signal Vc becomes a potential that is increased from the power supply potential by the forward voltage drop VF of the diode D2.

  The phase comparator 12 compares the edges of the output signal Vc and the timing signal Vr sent from the timing generation circuit when the phase comparison permission signal EN is at the H level. That is, the phase of the signal flowing through the LC resonator is compared with the phase of the reference clock signal input to the timing generation circuit 11.

  The phase difference voltage conversion circuit 13 receives the phase comparison result output from the phase comparator 12, and changes the frequency / phase of the resonance circuit by changing the capacitance value of the variable capacitor C1a depending on which is delayed or advanced. And the frequency and phase of the drive circuit are matched. The power transmission efficiency can be increased by matching the phases.

According to the power transmission device as described above, with respect to the frequency of the drive signal of the transmission circuit side LC resonator, even when the shift resonance frequency of the transmitting circuit side LC resonator, the transmitting circuit side LC resonator by changing the resonant frequency, is matched with the resonance frequency of the frequency and the transmitting circuit side LC resonator of the drive signal transmitting circuit side LC resonator, it is possible to prevent a decrease in transmission efficiency.

  FIG. 6 is an equivalent circuit diagram showing the principle of the configuration of the power transmission device according to the third embodiment of the present invention. In FIG. 6, in the power transmission device, a voltage source V1, which is a drive circuit, an internal resistance 10Ω of a voltage source, a capacitor C1 (= 5 pF), an internal resistance 2Ω of an inductor, and an inductor L1 (= 15 μH) are connected in series. To constitute a transmission side circuit.

  Further, the inductor L2, the internal resistance 2Ω of the inductor, the capacitor C2 (= C1 = 5 pF), and the parallel circuit of the capacitor Cp and the load resistance RL (= 50Ω) are connected in series to constitute a receiving side circuit. It is assumed that the inductors L1 and L2 are inductively coupled with a coupling coefficient k = 0.01.

  Here, as shown in FIG. 6A, the inductor L2 is increased to L2 = (1 + α) L1 = 15.3 μH, and at the same time, the capacitance Cp connected in parallel with the load resistor RL is Cp = C1 / α = 250 pF. To do.

  Alternatively, as shown in FIG. 6B, the capacitance C2 is increased to C2 = (1 + α) C1 = 5.1 pF, and at the same time, the capacitance Cp connected in parallel with the load resistor RL is set to Cp = C1 / α = 250 pF. .

In the power transmission device having such a configuration, the natural frequency of the LC resonator is lowered by slightly increasing the value of one or both of L2 and C2 constituting the receiving circuit side LC resonator. However, since the capacitance Cp connected in parallel with the load resistor RL is connected in series with the LC resonator, the capacitance component of the LC resonator becomes a series combined capacitance of C2 and Cp, and the oscillation frequency is changed to the transmission circuit side. It is possible to have the same desired value as the LC resonator.

を満足するαを、０．００１≦α≦０．０５、βを、０．９≦β≦１．１の範囲になるように定める。すなわち、Ｌ２を０．１％〜５％程度大きくする（α＝０．００１〜０．０５）のが実験的に好ましい。Ｌ２を元のＬ１から微増させてＬ２＝（１＋α）Ｌ１とした場合、並列容量はＣＰ＝Ｃ１／α＝Ｃ２／αが目安となる。 Here, when the resonance frequency of the transmission circuit side and the reception circuit side resonance circuit is ω / 2π,

Α satisfying the above is determined in a range of 0.001 ≦ α ≦ 0.05, and β in a range of 0.9 ≦ β ≦ 1.1. That is, it is experimentally preferable to increase L2 by about 0.1% to 5% (α = 0.001 to 0.05). When L2 is slightly increased from the original L1 so that L2 = (1 + α) L1, CP = C1 / α = C2 / α is a guideline for the parallel capacity.

  According to the power transmission device having such a configuration, when the coupling coefficient k between the inductors is low, the effect of widening the bandwidth with high transmission efficiency is exhibited while improving the maximum transmission efficiency. Further, when the coupling coefficient k is high, the maximum transmission efficiency does not change, but there is an effect that the frequency bandwidth with high transmission efficiency is widened.

  Next, the difference in load voltage between the prior art and this embodiment will be described.

FIG. 7A shows a conventional wireless power transmission circuit using magnetic resonance. As the voltages V _LC1 and V _{LC2 at} the midpoint between the inductor L and the capacitor C constituting the LC resonator, a resonator having a high Q value can be obtained with an amplitude several tens to several hundred times as large as the input amplitude. This is the same as the principle of gradually increasing the amplitude of the pendulum by applying a force having a small amplitude periodically to the pendulum with almost no friction loss. The voltage V2 that can be extracted by the load resistor RL on the receiving circuit side is smaller than the input voltage V1 due to radiation loss such as copper loss, iron loss, and radio wave of the coil.

FIG. 7B shows an example in which the capacitor constituting the receiving circuit side LC resonator is divided into two as compared with FIG. A circuit in which the combined capacitance is C1 is configured by C2 = 1.02 · C1 obtained by increasing C1 by 2%, for example, and a large capacitance Cp = 51 · C1 connected in series. According to such a configuration, the natural frequency of the LC resonator does not change. Here, paying attention to the midpoint voltage VCC2 of 1.02 · C1 and 51 · C1, the voltage of the node VLC2 swinging with a large amplitude is capacitively divided by two capacitive elements, so that the voltage is higher than V2. Amplitude is obtained.

  FIG. 7C is a circuit in which a large amplitude obtained at the intermediate node VLC2 having the above-described capacitance is extracted and applied to the load resistance. By adopting such a circuit configuration, it is possible to increase the voltage applied to the load on the power receiving side circuit and increase the power transmission efficiency.

  FIG. 8 shows the power transmission efficiency comparing the conventional method and this example. When the coils and capacitors of the transmission / reception circuit are configured symmetrically, the maximum voltage gain from the voltage source of the transmission side circuit to the load resistance of the reception side circuit is 92%. On the other hand, in the circuit in which C2 is added by increasing L2 by 2%, the maximum voltage gain is improved to 97%. Moreover, it turns out that the frequency band which can perform electric power transmission with high efficiency is wide.

  The power transmission device of the present invention can be applied in various forms such as a wireless power transmission device, contactless power supply to a memory cartridge, contactless power supply to a portable terminal, contactless power supply to a semiconductor chip, etc. Some examples will be described.

  An application example of the present invention is shown in FIG. The power transmission apparatus according to the present invention supplies wireless power to a memory card (data uses RF or the like) as shown in FIG. 9A, and is used for a mobile phone, digital camera, notebook PC, etc. as shown in FIG. 9B. It can be used for wireless power supply, and wireless power supply to electric vehicles.

  FIG. 10 is a configuration example of a semiconductor integrated circuit equipped with a transceiver circuit for wireless power transmission. In FIG. 10A, the transmission side chip 20 includes a power transmission circuit 21 and a control microcomputer 22. The receiving chip 30 includes a power receiving circuit 31 and a control microcomputer 32. The power transmission circuit 21 drives a resonance circuit of the capacitor C1 and the inductor L1, and the power reception circuit 31 receives power from the resonance circuit of the capacitor C2 and the inductor L2.

  Such a power transmission device is equipped with control microcomputers 22 and 32 for control of power transmission and reception (protocol control such as transmission start / stop, adjustment of transmission voltage, calibration of resonance frequency of LC tank of transmission / reception circuit). It is desirable to do. When applied to a non-contact memory card or the like, the power transmission circuit 21 is mounted on the host-side microcomputer chip, and the power reception circuit 31 is mounted on the cartridge-side memory chip. Moreover, it is preferable that the inductor L and the capacitor C constituting the LC resonator are disposed and connected outside the chip. The reason is that L and C having a high Q value are necessary (Q = 100 to 1000), and a signal having a voltage amplitude several hundred times as large as the power supply voltage of the chip appears at an intermediate node between L and C. This is because the device has insufficient breakdown voltage.

  In FIG. 10B, the transmission-side chip 20a includes a power transmission circuit 21, a microcomputer 22a, and a data transmission / reception circuit 23. The reception chip 30 a includes a power reception circuit 31, a data transmission / reception circuit 33, and a flash memory 34. The data transmission / reception circuits 23 and 33 transmit and receive data by transmitting fluctuations of radio waves, magnetic fields, electric fields, and the like to the other party using an antenna. According to such a configuration, the microcomputer 22 a can be controlled to store data in the flash memory 34 via the data transmission / reception circuits 23 and 33.

  FIG. 11 is a configuration example of a power transmission apparatus that also performs data communication by modulating a carrier of power to be transmitted and received. In FIG. 11, the transmission-side chip 20 b includes a power transmission circuit 21, a data transmission / reception circuit 23, and a modem 25. The receiving chip 30b includes a power receiving circuit 31, a data transmitting / receiving circuit 33, and a modem 35. The power transmission circuit 21 drives the resonance circuit of the capacitor C1 and the inductor L1 by the power signal modulated by the modem 25, and the power reception circuit 31 receives power from the resonance circuit of the capacitor C2 and the inductor L2. The data transmitting / receiving circuit 33 receives the signal demodulated by the modem 35 from the power signal.

  According to the power transmission device having such a configuration, data can be transmitted between two chips by adding minute amplitude modulation, frequency modulation, phase modulation, or the like to the power applied to the LC resonator. Using this data communication function, it is also possible to control power transmission / reception between two chips (setting of voltage and current, start / stop of power transmission, etc.).

  FIG. 12 shows an example in which data transmission / reception in FIG. 11 is performed using frequency modulation. In FIG. 12, the same reference numerals as those in FIG. The modulator 15 modulates the frequency control signal of the voltage controlled oscillator (VCO) 14 according to the value of the data Data, so that the oscillation frequency of the voltage controlled oscillator 14 changes. On the reception side, data is reproduced by reading a change in frequency or a change in amplitude (transmission efficiency changes as the resonance point shifts, resulting in a change in power on the reception side).

  FIG. 13 is an example in which the data transmission / reception of FIG. 11 is performed using amplitude modulation. In FIG. 13, the same reference numerals as those in FIG. The modulators 15a and 15b change the amplitude of the current supplied to the LC tank by changing the gate voltages of the PMOS transistor Mp and the NMOS transistor Mn that drive the LC tank according to the value of the data Data. The amount of power received by the side circuit changes. This change is read by the receiving side circuit and data is reproduced.

  FIG. 14 shows an example in which a transistor on which the control circuit shown in FIG. 1 and the like are mounted and a SiP (System in Package) are configured using a transistor for driving the LC tank as another chip. In FIG. 14, the transmission-side chip 20c includes a control chip 26, NMOS transistors Mn and PMOS transistors Mp that are power transistors. The NMOS transistor Mn and PMOS transistor Mp that drive the LC resonator need to be high power transistors in order to supply power to the receiving circuit. Since CMOS transistors used in ordinary integrated circuits are not suitable for such high power drive, large power can be efficiently transmitted by separately providing a transistor suitable for high power drive. .

  It should be noted that the disclosures of the aforementioned patent documents and the like are incorporated herein by reference. Within the scope of the entire disclosure (including claims) of the present invention, the embodiments and examples can be changed and adjusted based on the basic technical concept. Various combinations and selections of various disclosed elements are possible within the scope of the claims of the present invention. That is, the present invention of course includes various variations and modifications that could be made by those skilled in the art according to the entire disclosure including the claims and the technical idea.

11 Timing generation circuit 12 Phase comparator 13 Phase difference voltage conversion circuit 14 Voltage controlled oscillator 14a Oscillator 15, 15a, 15b Modulator 20, 20a, 20b, 20c Transmitting chip 21 Power transmission circuit 22, 32 Control microcomputer 22a Microcomputer 23, 33 Data transmission / reception circuit 25, 35 Modulator / demodulator 26 Control chip 30, 30a, 30b Reception side chip 31 Power reception circuit 34 Flash memory C1, C2, Cp Capacitor C1a Variable capacitance capacitor D1, D2 Diode L1, L2 Inductor Mn NMOS transistor Mp PMOS Transistor RL Load resistance V1 Voltage source

Claims (10)

Comprising a resonator between the transmit circuit and the receive circuit, said transmission circuit includes an oscillator, in a non-contact type power transmission device for transmitting to said receiving circuit power from said oscillator,
The oscillator is
It further includes a transmission circuit side resonator composed of a series connection of an inductor and a capacitor,
The transmission circuit includes:
A reference timing signal from the oscillator, via the output node, and output to the transmitting circuit side resonator, a driving dynamic circuit shall be the high impedance between the said output node of the desired period,
A phase comparator for comparing said desired during the period of the phase between the reference timing signal of the signal outputted from the transmitting circuit side resonator phase,
-Out based on the comparison result of the phase comparator, to change the frequency of the oscillator, and a control circuit for matching the frequency of the oscillator and the resonant frequency of the transmitting circuit side resonators,
Is provided on the transmission circuit side.   In a non-contact type power transmission device that includes a resonator between a transmission circuit and a reception circuit, the transmission circuit includes an oscillator, and transmits power from the oscillator to the reception circuit.
  The oscillator is
  It further includes a transmission circuit side resonator composed of a series connection of an inductor and a capacitor,
  The transmission circuit includes:
  A reference timing signal from the oscillator is output to the transmitting circuit side resonator via an output node, and the output node has a high impedance for a desired period; and
  A phase comparator that compares the phase of the signal output from the transmission circuit side resonator and the phase of the reference timing signal during the desired period;
  Based on the comparison result in the phase comparator, the control circuit changes the value of the capacitor of the transmission circuit side resonator, and matches the resonance frequency of the transmission circuit side resonator with the frequency of the oscillator;
  Is provided on the transmission circuit side. The drive circuit is composed of a CMOS circuit composed of a cascade connection of an NMOS transistor and a PMOS transistor. During the desired period, the NMOS transistor and the PMOS transistor are simultaneously turned off, so that the output node becomes high. The power transmission device according to claim 1 , wherein the power transmission device is an impedance . 4. The power transmission according to claim 3 , wherein the driving circuit sets a predetermined period before and after a point in time when a driving current for driving one end of the transmitting circuit side resonator crosses a zero level as the time when the driving circuit is in the off state. apparatus. The power transmission device according to claim 3 , wherein the drive circuit sets a time period during which the drive circuit is intermittently turned off. Comprising a resonator between the transmit circuit and the receive circuit, said transmission circuit includes an oscillator, in a non-contact type power transmission device for transmitting to said receiving circuit power from said oscillator,
Further comprising a configured transmitting circuit side resonator connected in series in the first inductor and the first capacitor,
A drive circuit that outputs a reference timing signal from the oscillator to the transmitting circuit side resonator via an output node, and sets the output node to high impedance for a desired period ;
A receiving circuit side resonator constituted by a series connection of a second inductor, a second capacitor, and a third capacitor;
A load resistor connected in parallel to the third capacitor;
With
The values of the first and second inductors are L ₁ and L ₂ , respectively.
The values of the first, second and third capacitors are C ₁ , C ₂ and C _p , respectively.
When the resonance frequency of the transmission circuit side and the reception circuit side resonance circuit is ω / 2π,

Α satisfying the above is defined such that 0.001 ≦ α ≦ 0.05, and β is within the range of 0.9 ≦ β ≦ 1.1. Power transmission device, characterized in that signals for driving the one end of the transmission circuit side resonator in the power transmission apparatus according is a signal modulated by the data signal in any one of claims 1 to 6. The power transmission device according to claim 7 , further comprising a voltage controlled oscillator that frequency-modulates or phase-modulates the reference timing signal with the data signal. The power transmission device according to claim 7 , further comprising a modulator that amplitude-modulates an output signal of the drive circuit by the data signal between the drive circuit and one end of the transmission circuit side resonator. The semiconductor integrated circuit device including a power transmission device according to any one of claims 1 to 9.

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