Antenna tuning IC

Abstract

To reduce a current consumption of an antenna tuning IC.SOLUTION: According to an embodiment, an antenna tuning IC contains: a power level detection circuit; a signal level determination circuit; and a current consumption control circuit. The power level detection circuit detects a power level of an antenna wire to which a high-frequency signal received by an antenna is transmitted. The signal level determination circuit determines a signal level detected by the power level detection circuit. The current consumption control circuit generates a switch gate control signal for controlling an ON / OFF operation of a RF switch part, and more reduces a first current consumption generated when the power level is a low input voltage on the basis of the signal level determination circuit than a second current consumption generated when it is in a high input voltage.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to an antenna tuning IC.

Background Art

[0002] An antenna tuning IC is installed near an antenna used for mobile communication or the like, and is used for aperture tuning of the antenna to adjust the antenna to a place with good radio waves by switching a switch.

[0003] Since the antenna tuning IC is installed near the antenna, a high RF breakdown voltage is required, and the current consumption increases for high breakdown voltage operation. In the field of mobile communication, power consumption reduction is essential. For this reason, in the antenna tuning IC installed in the analog front end unit, power consumption reduction is strongly demanded by users.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] An object of the present invention is to reduce the current consumption of an antenna tuning IC.

Means for Solving the Problems

[0006] According to one embodiment, the antenna tuning IC includes a power level detection circuit, a signal level discrimination circuit, and a current consumption control circuit. The power level detection circuit detects the power level of the antenna line through which the high-frequency signal received by the antenna is transmitted. The signal level discrimination circuit determines the signal level detected by the power level detection circuit. The current consumption control circuit generates a switch gate control signal to control the on / off operation of the RF switch section and reduces the first current consumption that occurs when the power level is low input voltage to a second current consumption that occurs when the power level is high input voltage, based on the signal level discrimination circuit. [Brief explanation of the drawing]

[0007] [Figure 1] This is a circuit diagram showing an antenna tuning IC according to the first embodiment. [Figure 2] This is a circuit diagram showing an antenna tuning IC for a comparative example. [Figure 3] A timing chart showing the operation of the antenna tuning IC according to the first embodiment. [Figure 4] This diagram shows the operation of the antenna tuning IC in the comparative example. [Figure 5] This figure shows the change in current consumption of the antenna tuning IC according to the first embodiment. [Figure 6] This is a comparison diagram of the current consumption of the antenna tuning IC according to the first embodiment and the antenna tuning IC of the comparative example. [Figure 7] This is a circuit diagram showing an antenna tuning IC according to the second embodiment. [Figure 8] A timing chart showing the operation of the antenna tuning IC according to the second embodiment. [Figure 9] This is a circuit diagram showing an antenna tuning IC according to the third embodiment. [Figure 10] A timing chart showing the operation of the antenna tuning IC according to the third embodiment. [Figure 11] This is a schematic diagram illustrating a mobile phone communication module equipped with an antenna tuning IC.

[0008] Embodiments of the present invention will be described below with reference to the drawings.

[0009] (First embodiment) First, the antenna tuning IC according to the first embodiment will be described with reference to the drawings. Figure 1 is a circuit diagram showing the antenna tuning IC.

[0010] In the first embodiment, a power level detection circuit for detecting the power level of the antenna wire, a signal level discrimination circuit for determining the detected signal level, an RF switch section equipped with a multi-stage stacked MOS transistor, and a current consumption control circuit that controls the on / off state of the RF switch section and varies the signal level of the switch gate control signal input to the gate of the multi-stage stacked MOS transistor based on the signal level discrimination result are provided, thereby reducing the first current consumption that occurs when the power level of the antenna wire is a low input voltage to a second current consumption that occurs when the power level of the antenna wire is a high input voltage.

[0011] The antenna tuning IC1 is applied to various wireless communication systems. For example, the antenna tuning IC1 is mounted in the analog front end of a mobile phone communication module used in smartphones, mobile phone terminals, etc., as shown in Figure 11. Specifically, the mobile phone communication module 100 includes the antenna tuning IC1, antenna 2, antenna wire 3, analog front end module (AFE module) 20, and RF communication processing unit (BBLSI) 30. The antenna tuning IC1 is also used in mobile terminals, for example.

[0012] Antenna 2 receives high-frequency radio wave signals. Antenna wire 3 transmits the signals received by antenna 2. Antenna tuning IC 1 is located near antenna 2 (between antenna 2 and analog front-end module 20) and is used for antenna aperture tuning, adjusting the antenna to a location with good radio wave reception using a switch. Analog front-end module 20 includes a duplexer 21, a receiver 22, and a transmitter 23. The duplexer 21 is connected to antenna wire 3 and switches between transmitting and receiving wireless communication. The receiver 22 amplifies the received wireless communication signal output from the duplexer 21 and outputs it to the RF communication processing unit (BBLSI) 30. The transmitter 22 amplifies the communication processing signal output from the RF communication processing unit (BBLSI) 30 and outputs it to the duplexer 21. The RF communication processing unit (BBLSI) 30 is a baseband LSI that performs various processes related to transmitting and receiving in RF communication.

[0013] As shown in Figure 1, the antenna tuning IC 1 is connected to the antenna line 3 that transmits the received signal output from the antenna 2 that receives high-frequency radio wave signals. The antenna tuning IC 1 includes a full-wave rectifier circuit 11, a comparator 12, a ring oscillator 13, a boost charge pump circuit / boost regulator 14, a buck charge pump circuit / buck regulator 15, a level shifter 16, and an RF switch section 40.

[0014] The full-wave rectifier circuit 11 (power level detection circuit) receives the received signal from antenna 2 via antenna wire 3. The full-wave rectifier circuit 11 functions as a power level detection circuit that detects the power level (node ​​N1) of antenna wire 3. The full-wave rectifier circuit 11 outputs the absolute value of the input voltage and is also called an absolute value circuit. It has the function of converting the input voltage AC (alternating current voltage) to DC (direct current voltage).

[0015] Comparator 12 (signal level discrimination circuit) receives the output of the full-wave rectifier circuit 11 (the signal at node N2) and the reference voltage Vref, compares them, and outputs a signal obtained by comparison and amplification. Comparator 12 functions as a signal level discrimination circuit that discriminates the signal level of the full-wave rectifier circuit 11. When the output of the full-wave rectifier circuit 11 (the signal at node N2) is smaller than the reference voltage Vref, Comparator 12 outputs a low-level (“L”) signal, and when the output of the full-wave rectifier circuit 11 (the signal at node N2) is larger than the reference voltage Vref, it outputs a high-level (“H”) signal.

[0016] Ring oscillator 13 functions as an oscillator that generates an oscillation signal. Boost charge pump circuit · boost regulator 14 receives the oscillation signal (the signal at node N4) output from ring oscillator 13. The boost charge pump circuit generates a boosted voltage Vp based on the oscillation signal (the output at node N4) that is the output of ring oscillator 13. The boost regulator performs feedback processing on the boosted voltage Vp generated by the boost charge pump circuit to make the boosted voltage Vp a constant value. The boosted voltage Vp is a positive voltage.

[0017] Buck charge pump circuit · buck regulator 15 receives the oscillation signal (the signal at node N4) output from ring oscillator 13 and the output of comparator 12 (the signal at node N3). The buck charge pump circuit generates a buck voltage Vn based on the oscillation signal (the output at node N4) that is the output of ring oscillator 13. The buck regulator performs feedback processing on the buck voltage Vn generated by the buck charge pump circuit to generate two types of buck voltages Vn with different voltage values based on the output of comparator 12 (the signal at node N3). Specifically, when the output of comparator 12 is at a low level (“L”), the buck voltage Vn is set to a first negative voltage. When the output of comparator 12 is at a high level (“H”), the buck voltage Vn is set to a second negative voltage at a deeper level with an absolute value larger than that of the first negative voltage.

[0018] For the boost charge pump circuit (boost circuit) and the buck charge pump circuit (buck circuit), a Dickson type charge pump circuit, a charge pump circuit using a bootstrap gate transfer switch, etc. are used. For the boost regulator and the buck regulator, a switching type DC / DC converter, etc. are used.

[0019] The level shifter 16 inputs the outputs of the boost charge pump circuit - boost regulator 14 (the signal of node N5 (boost voltage Vp)) and the buck charge pump circuit - buck regulator 15 (the signal of node N6 (buck voltage Vn)), generates a level - shifted signal, and outputs it to the RF switch section 40 as the switch gate control signal Ssg1. The switch gate control signal Ssg1 output from the level shifter 16 is set to the boost voltage Vp when it is at a high level and set to the buck voltage Vn when it is at a low level. The RF switch section 40 operates in an on - off manner according to the switch gate control signal Ssg1 output from the level shifter 16.

[0020] The ring oscillator 13, the boost charge pump circuit - boost regulator 14, the buck charge pump circuit - buck regulator 15, and the level shifter 16 function as a current consumption control circuit that controls the on - off of the RF switch section 40 and controls the current consumption of the antenna tuning IC1.

[0021] The RF switch section 40 includes cascaded multi - stage stacked MOSFETs. The RF switch section 40 inputs the switch gate control signal Ssg1 (the signal of node N7) output from the level shifter 16 and operates in an on - off manner based on the switch gate control signal Ssg1. The reason for setting the voltage at the low level of the switch gate control signal Ssg1 to a negative voltage is to ensure the off - state breakdown voltage of the RF switch section 40 when the power level of the antenna line is at a high input voltage.

[0022] Next, the antenna tuning IC of the comparative example will be described with reference to FIG. 2. FIG. 2 is a circuit diagram showing the antenna tuning IC of the comparative example.

[0023] As shown in Figure 2, the comparative example antenna tuning IC 5 includes a ring oscillator 13, a boost charge pump circuit / boost regulator 14, a buck charge pump circuit / buck regulator 15a, a level shifter 16, and an RF switch section 40. The comparative example antenna tuning IC 5 does not have the full-wave rectifier circuit 11 and comparator 12 of the antenna tuning IC 1 of this embodiment. The description of the same components as the antenna tuning IC 1 of this embodiment will be omitted, and only the different components will be described.

[0024] The buck charge pump circuit and buck regulator 15a receive the oscillation signal (signal from node N4) output from the ring oscillator 13. The buck charge pump circuit generates a buck voltage Vn based on the oscillation signal (output from node N4), which is the output of the ring oscillator 13. The buck regulator processes the buck voltage Vn generated by the buck charge pump circuit using feedback to generate a constant buck voltage Vn.

[0025] In the comparative example antenna tuning IC5, the low level of the switch control signal ssg1, which controls the on / off operation of the multi-stage stacked MOS transistors in the RF switch section 40, is set to a step-down voltage Vn, which is a constant negative voltage regardless of the high or low input voltage of the antenna line's power level.

[0026] Next, the operation of the antenna tuning IC will be explained with reference to Figures 3 and 4. Figure 3 is a timing chart showing the operation of the antenna tuning IC of this embodiment. Figure 4 is a diagram showing the operation of the antenna tuning IC of a comparative example. Note that in the timing chart of Figure 3, it is simply shown that the voltage is input to the antenna wire in the order of low input voltage ⇒ high input voltage ⇒ low input voltage.

[0027] As shown in Figure 3, in the antenna tuning IC1, the full-wave rectifier circuit 11 receives the received signal from the antenna wire 3 (node ​​N1) to the antenna 2. The full-wave rectifier circuit 11 detects the power level of the antenna wire 3. The full-wave rectifier circuit 11 outputs a low voltage when the power level of the antenna wire 3 is a low input voltage, and outputs a high voltage when the power level of the antenna wire 3 is a high input voltage.

[0028] The comparator 12 receives the output signal from the full-wave rectifier circuit 11. The comparator 12 outputs a low-level ("L") signal when the output of the full-wave rectifier circuit 11 is below the reference voltage Vref, and outputs a high-level ("H") signal when the output of the full-wave rectifier circuit 11 is above the reference voltage Vref.

[0029] The buck charge pump circuit / buck regulator 15 receives the output signal from the comparator 12. When the output of the comparator 12 is at a low level ("L"), the buck charge pump circuit / buck regulator 15 generates a buck voltage Vn, for example -1.5V, and outputs it to the level shifter 16. When the output of the comparator 12 is at a high level ("H"), the buck charge pump circuit / buck regulator 15 generates a buck voltage Vn, for example -3.0V, and outputs it to the level shifter 16.

[0030] In this embodiment, the antenna tuning IC1 generates a step-down voltage Vn of -1.5V when the power level of the antenna wire 3 is at a low input voltage, and generates a step-down voltage Vn of -3.0V when the power level of the antenna wire 3 is at a high input voltage. The operating current (first operating current) when the step-down voltage Vn of -1.5V is generated by the step-down charge pump circuit and step-down regulator 15 is smaller than the operating current (second operating current) when the step-down voltage Vn of -3.0V is generated by the step-down charge pump circuit and step-down regulator 15 because the capacity of the charge pump can be reduced. As a result, the current consumption of the antenna tuning IC1 when the power level of the antenna wire 3 is at a low input voltage can be reduced compared to the current consumption of the antenna tuning IC1 when the power level of the antenna wire 3 is at a high input voltage.

[0031] In the comparative example antenna tuning IC5, the step-down charge pump circuit / step-down regulator 15a generates a step-down voltage Vn, for example, -3.0V, regardless of the power level of the antenna wire 3.

[0032] Therefore, as shown in Figure 4, the current consumption of the antenna tuning IC 5 remains constant regardless of the output power of antenna 2.

[0033] Next, the current consumption of the antenna tuning IC will be explained with reference to Figures 5 and 6. Figure 5 is a diagram showing the change in current consumption of the antenna tuning IC of this embodiment. Figure 6 is a comparison diagram of the current consumption of the antenna tuning IC of this embodiment and the antenna tuning IC of the comparative example. In Figure 5, the current consumption of the antenna tuning IC of the comparative example is shown with a dashed line.

[0034] As shown in Figure 5, in the antenna tuning IC, the antenna output power changes according to frequency. In the region where the antenna output power is low, the frequency is low, and as the antenna output power increases, the frequency increases, reaching a peak at a certain point and then decreasing. For example, it follows a normal distribution shape.

[0035] In this embodiment, when the output power of the antenna 2 falls below a predetermined detection power level, the step-down charge pump circuit / step-down regulator 15 generates a step-down voltage Vn of -1.5V. Therefore, the current consumption of the antenna tuning IC 1 in this embodiment can be reduced compared to the current consumption of the antenna tuning IC 5 in the comparative example shown by the dashed line.

[0036] As shown in Figure 6, the current consumption generated during the operation of the antenna tuning IC1 of this embodiment can be reduced by, for example, 48% compared to the current consumption generated during the operation of the comparative example antenna tuning IC5. Here, the comparison diagram of the antenna tuning IC current consumption shown in Figure 6 is an example where the detection power level is set to a predetermined value, the frequency distribution of the output power of antenna 2 shows a normal distribution (see Figure 5), and it is installed in a smartphone. The effect of reducing current consumption will differ when the communication frequency and communication frequency are different, such as in mobile phone terminals and mobile telephone terminals.

[0037] As described above, the antenna tuning IC1 of this embodiment is provided with a full-wave rectifier circuit 11, a comparator 12, a ring oscillator 13, a boost charge pump circuit / boost regulator 14, a buck charge pump circuit / buck regulator 15, a level shifter 16, and an RF switch section 40. The full-wave rectifier circuit 11 functions as a power level detection circuit that detects the power level of the antenna wire 3. The comparator 12 functions as a signal level discrimination circuit that determines the signal level detected by the full-wave rectifier circuit 11. The ring oscillator 13, boost charge pump circuit / boost regulator 14, buck charge pump circuit / buck regulator 15, and level shifter 16 function as a current consumption control circuit that controls the on / off operation of the RF switch section 40 and controls the current consumption of the antenna tuning IC1. The step-down charge pump circuit / step-down regulator 15 generates a step-down voltage Vn of -1.5V when the power level of the antenna line 3 is a low input voltage, and generates a step-down voltage Vn of -3.0V when the power level of the antenna line 3 is a high input voltage, based on the discrimination result output from the comparator 12. The level shifter 16 receives the boost voltage Vp, which is a constant voltage generated by the boost charge pump circuit / boost regulator 14, and the step-down voltages Vn of -1.5V and -3.0V generated by the step-down charge pump circuit / step-down regulator 15 as inputs. The level shifter 16 outputs a switch gate control signal Ssg1 to the RF switch unit 40, which is set to the boost voltage Vp when the level is high, to the step-down voltage Vn of -3.0V when the level is low and the power level is a high input voltage, and to the step-down voltage Vn of -1.5V when the level is low and the power level is a low input voltage.

[0038] Therefore, the first current consumption of the antenna tuning IC1 that occurs when the power level is low input voltage can be reduced to the second current consumption of the antenna tuning IC1 that occurs when the power level is high input voltage. Thus, the power consumption of the antenna tuning IC1 can be reduced.

[0039] In this embodiment, the antenna tuning IC1 uses a boost charge pump circuit / boost regulator 14 and a buck charge pump circuit / buck regulator 15, but is not necessarily limited to these. For example, instead of a boost regulator, a comparator that performs boost voltage feedback operation may be used for feedback operation. Instead of a buck regulator, a selector that takes the output of comparator 12 as input and a comparator that performs buck voltage feedback operation may be used for feedback operation.

[0040] (Second embodiment) Next, the antenna tuning IC according to the second embodiment will be described with reference to the drawings. Figure 7 is a circuit diagram showing the antenna tuning IC.

[0041] In the second embodiment, the step-down charge pump circuit is equipped with a standby function to generate two types of step-down voltages different from those in the first embodiment.

[0042] In the following description, components identical to those in the first embodiment are denoted by the same reference numerals, and their descriptions are omitted; only the different components will be described.

[0043] As shown in Figure 7, the antenna tuning IC 1a includes a full-wave rectifier circuit 11, a comparator 12, a ring oscillator 13, a boost charge pump circuit / boost regulator 14, a buck charge pump circuit / buck regulator with standby function 17, a level shifter 16, and an RF switch section 40. The antenna tuning IC 1a is applied to, for example, smartphones, mobile phone terminals, and mobile terminals.

[0044] The buck charge pump circuit with standby function and buck regulator 17 receive the oscillation signal (signal at node N4) output from the ring oscillator 13 and the output of the comparator 12 (signal at node N3). The buck charge pump circuit with standby function switches between active and standby modes based on the output of the comparator 12 (signal at node N3). When active, the output is set to the buck voltage Vn, and when in standby mode, it stops operating and the output becomes the ground potential Vss level. The buck regulator processes the buck voltage Vn generated by the buck charge pump circuit with standby function as feedback, and when the buck charge pump circuit with standby function stops operating, the output becomes the ground potential Vss level.

[0045] The buck charge pump circuit with standby function and buck regulator 17 has its output set to ground potential Vss when the output of comparator 12 is at a low level ("L"). When the output of comparator 12 is at a high level ("H"), its output is set to the buck voltage Vn (second negative voltage).

[0046] The level shifter 16 receives the output of the boost charge pump circuit / boost regulator 14 (signal at node N5 (boost voltage Vp)) and the output of the buck charge pump circuit / buck regulator 17 with standby function (signal at node N6 (buck voltage Vn)), generates a level-shifted signal, and outputs it to the RF switch unit 40 as a switch gate control signal Ssg1. When the switch gate control signal Ssg1 output from the level shifter 16 is high level, it is set to the boost voltage Vp, and when it is low level, it is set to the buck voltage Vn (second negative voltage) or ground potential Vss. The RF switch unit 40 is turned on and off by the switch gate control signal Ssg1 output from the level shifter 16.

[0047] Next, the operation of the antenna tuning IC will be explained with reference to Figure 8. Figure 8 is a timing chart showing the operation of the antenna tuning IC in this embodiment.

[0048] As shown in Figure 8, in the antenna tuning IC1a, the full-wave rectifier circuit 11 receives the received signal from the antenna wire 3 (node ​​N1) to the antenna 2. The full-wave rectifier circuit 11 detects the power level of the antenna wire 3. The full-wave rectifier circuit 11 outputs a low voltage when the power level of the antenna wire 3 is a low input voltage, and outputs a high voltage when the power level of the antenna wire 3 is a high input voltage.

[0049] The comparator 12 receives the output signal from the full-wave rectifier circuit 11. The comparator 12 outputs a low-level ("L") signal when the output of the full-wave rectifier circuit 11 is below the reference voltage Vref, and outputs a high-level ("H") signal when the output of the full-wave rectifier circuit 11 is above the reference voltage Vref.

[0050] The buck charge pump circuit with standby function and buck regulator 17 receives the oscillation signal (signal at node N4) output from the ring oscillator 13 and the output of the comparator 12 (signal at node N3). When the output of the comparator 12 is low level ("L"), the buck charge pump circuit with standby function and buck regulator 17 enters standby mode and stops operating, its output becomes ground potential Vss level, and it outputs a signal at ground potential Vss level to the level shifter 16. When the output of the comparator 12 is high level ("H"), the buck charge pump circuit with standby function and buck regulator 17 enters active mode, generates a buck voltage Vn, for example -3.0V, and outputs it to the level shifter 16.

[0051] Here, the buck charge pump circuit with standby function and buck regulator 17 enters standby mode and stops operating when the output of the comparator 12 is at a low level ("L"), and the buck voltage Vn becomes the ground potential Vss. At this time, since the power level of the antenna wire 3 is small, the RF switch unit 40 can stop operating and be completely turned off even at the ground potential Vss level.

[0052] In the antenna tuning IC1a of this embodiment, when the power level of the antenna wire 3 is a low input voltage, the buck charge pump circuit with standby function and buck regulator 17 stops operating and outputs a buck voltage Vn that is the ground potential Vss. When the power level of the antenna wire 3 is a high input voltage, the buck charge pump circuit with standby function and buck regulator 17 outputs a buck voltage Vn that is -3.0V. The operating current (first operating current) when the buck charge pump circuit with standby function and buck regulator 17 generates the buck voltage Vn that is the ground potential Vss is smaller than the operating current (second operating current) when the buck charge pump circuit with standby function and buck regulator 17 generates the buck voltage Vn that is -3.0V.

[0053] As described above, the antenna tuning IC1a of this embodiment is provided with a full-wave rectifier circuit 11, a comparator 12, a ring oscillator 13, a boost charge pump circuit / boost regulator 14, a buck charge pump circuit / buck regulator with standby function 17, a level shifter 16, and an RF switch unit 40. The full-wave rectifier circuit 11 functions as a power level detection circuit that detects the power level of the antenna wire 3. The comparator 12 functions as a signal level discrimination circuit that determines the signal level detected by the full-wave rectifier circuit 11. The ring oscillator 13, boost charge pump circuit / boost regulator 14, buck charge pump circuit / buck regulator with standby function 17, and level shifter 16 function as a current consumption control circuit that controls the on / off operation of the RF switch unit 40 and controls the current consumption of the antenna tuning IC1a. The standby-function buck charge pump circuit / buck regulator 17 outputs the ground potential Vss when the power level of the antenna line 3 is at a low input voltage, and outputs a buck voltage Vn of -3.0V when the power level of the antenna line 3 is at a high input voltage, based on the determination result output from the comparator 12. The level shifter 16 receives the boost voltage Vp, which is a constant voltage generated by the boost charge pump circuit / boost regulator 14, and the buck voltage Vn of the ground potential Vss generated by the standby-function buck charge pump circuit / buck regulator 17, as well as the buck voltage Vn of -3.0V. The level shifter 16 outputs a switch gate control signal Ssg1 to the RF switch unit 40, which is set to the boost voltage Vp when the level is high, the buck voltage Vn of -3.0V when the level is low and the power level is at a high input voltage, and the buck voltage Vn of the ground potential Vss when the level is low and the power level is at a low input voltage.

[0054] Therefore, the first current consumption of the antenna tuning IC1a that occurs when the power level is low input voltage can be reduced to the second current consumption of the antenna tuning IC1a that occurs when the power level is high input voltage. Thus, the power consumption of the antenna tuning IC1a can be reduced. Note that the effect of reducing current consumption in this embodiment is the same as the effect of reducing current consumption in the first embodiment.

[0055] (Third embodiment) Next, the antenna tuning IC according to the third embodiment will be described with reference to the drawings. Figure 9 is a circuit diagram showing the antenna tuning IC.

[0056] In the third embodiment, the power level of the antenna wire is detected by a directional coupler, and the control unit (controller) determines the detected signal level.

[0057] In the following description, components identical to those in the first embodiment are denoted by the same reference numerals, and their descriptions are omitted; only the different components will be described.

[0058] As shown in Figure 9, the antenna tuning IC1b includes a directional coupler 18, a control unit (controller) 19, a ring oscillator 13, a boost charge pump circuit / boost regulator 14, a buck charge pump circuit / buck regulator with standby function 17, a level shifter 16, and an RF switch unit 40. The antenna tuning IC1b is applied to, for example, smartphones, mobile phone terminals, and mobile terminals.

[0059] The directional coupler 18 is a measuring device inserted into the transmission line, and is a 4-port circuit configured as, for example, a 3-terminal or 4-terminal device. The directional coupler 18 functions as a power level detection circuit that detects the power level (node ​​N1) of the antenna line 3.

[0060] The control unit (controller) 19 receives the signal detected by the directional coupler 18 (the signal from node N8) and generates a control signal Sen according to the power level of the directional coupler 18. The control unit (controller) 19 generates a high-level ("H") control signal Sen when it determines that the power level of the antenna wire 3 is a high input voltage, and generates a low-level ("L") control signal Sen when it determines that the power level of the antenna wire 3 is a low input voltage.

[0061] The buck charge pump circuit with standby function and buck regulator 17 receive the oscillation signal (signal at node N4) output from the ring oscillator 13 and the output of the control unit (controller) 19 (signal at node N9). The buck charge pump circuit with standby function switches between active and standby modes based on the output of the control unit (controller) 19 (signal at node N9). When active, the output is set to the buck voltage Vn, and when in standby mode, it stops operating and the output becomes the ground potential Vss level. The buck regulator processes the buck voltage Vn generated by the buck charge pump circuit with standby function as feedback, and when the buck charge pump circuit with standby function stops operating, the output becomes the ground potential Vss level.

[0062] The buck charge pump circuit with standby function and buck regulator 17 have their output set to ground potential Vss when the output of the control unit (controller) 19 is at a low level ("L"). When the output of the control unit (controller) 19 is at a high level ("H"), the output is set to the buck voltage Vn (second negative voltage).

[0063] The level shifter 16 receives the output of the boost charge pump circuit / boost regulator 14 (signal at node N5 (boost voltage Vp)) and the output of the buck charge pump circuit / buck regulator 17 with standby function (signal at node N6 (buck voltage Vn)), generates a level-shifted signal, and outputs it to the RF switch unit 40 as a switch gate control signal Ssg1. When the switch gate control signal Ssg1 output from the level shifter 16 is high level, it is set to the boost voltage Vp, and when it is low level, it is set to the buck voltage Vn (second negative voltage) or ground potential Vss. The RF switch unit 40 is turned on and off by the switch gate control signal Ssg1 output from the level shifter 16.

[0064] Next, the operation of the antenna tuning IC will be explained with reference to Figure 10. Figure 10 is a timing chart showing the operation of the antenna tuning IC in this embodiment.

[0065] As shown in Figure 10, the antenna tuning IC 1b receives the received signal from antenna wire 3 (node ​​N1) via antenna 2 into the directional coupler 18. The directional coupler 18 detects the power level of antenna wire 3.

[0066] The control unit (controller) 19 receives the output signal from the directional coupler 18 (the signal from node N8). The control unit (controller) 19 outputs a low-level ("L") signal when it determines that the power level of the antenna wire 3 is a low input voltage, and outputs a high-level ("H") signal when it determines that the power level of the antenna wire 3 is a high input voltage.

[0067] The buck charge pump circuit with standby function and buck regulator 17 receives the oscillation signal (signal at node N4) output from the ring oscillator 13 and the output signal (signal at node N9) from the control unit (controller) 19. When the output of the control unit (controller) 19 is at a low level ("L"), the buck charge pump circuit with standby function and buck regulator 17 enters standby mode and stops operating, its output becomes at the ground potential Vss level, and it outputs a signal at the ground potential Vss level to the level shifter 16. When the output of the control unit (controller) 19 is at a high level ("H"), the buck charge pump circuit with standby function and buck regulator 17 enters active mode, generates a buck voltage Vn, for example -3.0V, and outputs it to the level shifter 16.

[0068] Here, the buck charge pump circuit / buck regulator 17 with standby function enters standby mode and stops operating when the output of the control unit (controller) 19 is at a low level ("L"), and the buck voltage Vn becomes the ground potential Vss. At this time, since the power level of the antenna wire 3 is small, the RF switch unit 40 can stop operating and be completely turned off even at the ground potential Vss level.

[0069] In the antenna tuning IC1b of this embodiment, when the power level of the antenna wire 3 is a low input voltage, the buck charge pump circuit with standby function and buck regulator 17 stops operating and outputs a buck voltage Vn that is the ground potential Vss. When the power level of the antenna wire 3 is a high input voltage, the buck charge pump circuit with standby function and buck regulator 17 outputs a buck voltage Vn that is -3.0V. The operating current (first operating current) when the buck charge pump circuit with standby function and buck regulator 17 generates the buck voltage Vn that is the ground potential Vss is smaller than the operating current (second operating current) when the buck charge pump circuit with standby function and buck regulator 17 generates the buck voltage Vn that is -3.0V.

[0070] As described above, the antenna tuning IC1b of the third embodiment is provided with a directional coupler 18, a control unit (controller) 19, a ring oscillator 13, a boost charge pump circuit / boost regulator 14, a buck charge pump circuit / buck regulator with standby function 17, a level shifter 16, and an RF switch unit 40. The directional coupler 18 functions as a power level detection circuit that detects the power level of the antenna wire 3. The control unit (controller) 19 functions as a signal level discrimination circuit that determines the signal level detected by the directional coupler 18. The ring oscillator 13, boost charge pump circuit / boost regulator 14, buck charge pump circuit / buck regulator with standby function 17, and level shifter 16 function as a current consumption control circuit that controls the on / off operation of the RF switch unit 40 and controls the current consumption of the antenna tuning IC1b. The buck charge pump circuit / buck regulator 17 with standby function outputs the ground potential Vss when the power level of the antenna line 3 is a low input voltage, and outputs a buck voltage Vn of -3.0V when the power level of the antenna line 3 is a high input voltage, based on the discrimination result output from the control unit (controller) 19. The level shifter 16 receives the boost voltage Vp, which is a constant voltage generated by the boost charge pump circuit / boost regulator 14, and the buck voltage Vn of the ground potential Vss and the buck voltage Vn of -3.0V generated by the buck charge pump circuit / buck regulator 15 as inputs. The level shifter 16 outputs a switch gate control signal Ssg1 to the RF switch unit 40, which is set to the boost voltage Vp when the level is high, the buck voltage Vn of -3.0V when the level is low and the power level is a high input voltage, and the buck voltage Vn of the ground potential Vss when the level is low and the power level is a low input voltage.

[0071] Therefore, the first current consumption of the antenna tuning IC1b that occurs when the power level is low input voltage can be reduced to the second current consumption of the antenna tuning IC1b that occurs when the power level is high input voltage. Thus, the power consumption of the antenna tuning IC1b can be reduced. Note that the effect of reducing current consumption in this embodiment is the same as the effect of reducing current consumption in the first embodiment.

[0072] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0073] 1, 1a, 1b, 5 Antenna Tuning ICs 2 antennas 3 Antenna wire 11 Full wave rectifier circuit 12 Comparators 13 Ring Oscillator 14. Boost Charge Pump Circuit / Boost Regulator 15, 15a Step-down charge pump circuit / Step-down regulator 16 Level Shifter 17. Step-down charge pump circuit with standby function / Step-down regulator 18 Directional coupler 19. Control Unit (Controller) 20 Analog Front-End Modules 21 Duplexer 22 Receiving section 23 Transmitter 30 RF Communication Processing Unit (BBLSI) 40 RF Switch Section Nodes N1-N9 Sen control signals Ssg1 Switchgate Control Signal Vn Step-down voltage Vout output voltage Vp Boost Voltage Vref Reference Voltage Vss Ground potential

Claims

1. A power level detection circuit that detects the power level of the antenna line through which the high-frequency signal received by the antenna is transmitted, A signal level discrimination circuit that determines the signal level detected by the power level detection circuit, A current consumption control circuit generates a switch gate control signal to control the on / off operation of the RF switch section, and based on the signal level determined by the signal level discrimination circuit, reduces the first current consumption that occurs when the power level is low input voltage to a second current consumption that occurs when the power level is high input voltage. An antenna tuning IC characterized by comprising the following features.

2. The current consumption control circuit sets the voltage of the switch gate control signal at a low level to a first negative voltage or ground potential when the power level is a low input voltage, and to a second negative voltage with a larger absolute value than the first negative voltage when the power level is a high input voltage. The antenna tuning IC described in item 1.

3. The current consumption control circuit includes a step-down charge pump circuit and a step-down regulator. The step-down charge pump circuit and step-down regulator generate the first negative voltage and the second negative voltage based on the determination result of the signal level determination circuit. The antenna tuning IC described in item 2.

4. The current consumption control circuit includes a step-down charge pump circuit with standby function and a step-down regulator. The aforementioned step-down charge pump circuit with standby function and step-down regulator generate the second negative voltage and the ground potential based on the determination result of the signal level determination circuit. The antenna tuning IC described in item 2.

5. The antenna tuning IC according to any one of claims 1 to 4, characterized in that the power level detection circuit uses a full-wave rectifier circuit or a directional coupler.

6. The antenna tuning IC according to any one of claims 1 to 4, characterized in that the signal level discrimination circuit uses a comparator or a controller.

7. The antenna tuning IC according to any one of claims 1 to 4, characterized in that the RF switch section has a multi-stage stacked MOS transistor to which the switch gate control signal is input to the gate.

8. The antenna tuning IC is characterized by being applicable to smartphones, mobile phone terminals, and mobile terminals, as described in any one of claims 1 to 4.

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