JP2002010155A - Integrated circuit for radio terminal and television receiver using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make this television receiver further compact and thin, to reduce the manufacturing costs, and to shorten a designing time by realizing the further integration of a circuit necessary for constituting this television receiver. SOLUTION: Tuners 2 and 3 and at least an electronic volume 4 are integrated on one semiconductor chip 10 in a CMOS structure so that the much more parts of a voice system circuit can be gathered into one chip. Thus, it is possible to reduce the number of parts, and to make this television receiver further compact and thin. Moreover, it is possible to make it unnecessary to separately design or manufacture the tuners 2 and 3 and the electronic volume 4, and it is possible to realize the design and manufacture in a batch on one semiconductor chip 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrated circuit for a radio terminal and a television receiver using the same. For example, a predetermined structure required for receiving and processing a television broadcast is provided on the same semiconductor substrate ( This is suitable for use in a circuit integrated on a chip.

[0002]

2. Description of the Related Art FIG. 4 is a diagram showing a general configuration of a television receiver for receiving an analog television broadcast. In FIG. 4, a radio wave for television broadcast received by an antenna 41 is input to a tuner 42. The tuner 42 generates and outputs an intermediate frequency (IF) signal by mixing the high-frequency television signal input from the antenna 41 with a signal of a local oscillation frequency controlled according to a desired reception frequency.

[0003] The IF signal extracted by the tuner 42 is amplified by an intermediate frequency amplifier (IF amplifier) 43, and then video-detected by a video detection circuit 44 and audio-detected by an audio detection circuit 45. The signal output from the video detection circuit 44 is
6, the image signal is separated into a luminance signal and a chrominance signal, and further subjected to predetermined image signal processing to become an image signal.
It is output to a display device such as T or LCD. The signal output from the audio detection circuit 45 is subjected to processing such as FM demodulation by the audio processing circuit 47 to become an audio signal, and is appropriately amplified and output to a speaker (not shown) or the like.

FIG. 5 is a diagram showing the structure of the tuner 42. In FIG. 5, a high frequency television signal for television broadcast received by an antenna 41 is a band-pass filter (B
The signal is input to one input terminal of a mixer 54 via a PF 51, a high frequency amplifier (RF amplifier) 52, and a band pass filter (BPF) 53. A local oscillation signal having a local oscillation frequency output from a frequency conversion oscillator (VCO) 55 is input to the other input terminal of the mixer 54.

The local oscillation frequency of the signal output from the VCO 55 is controlled by a PLL (Phase Locked Loop) circuit 56.
Is controlled according to the set desired reception frequency. The mixer 54 generates an intermediate frequency (IF) signal by mixing the high-frequency television signal output from the BPF 53 and the local oscillation signal output from the VCO 55, and outputs the intermediate frequency (IF) signal to the IF amplifier 43 in the next stage. Note that the tuner 42 may include the IF amplifier 43 in some cases.

[0006] In recent years, television receivers have begun to start digital broadcasting such as digital satellite broadcasting, terrestrial digital broadcasting, and cable television broadcasting using BS (broadcast satellite) and CS (communication satellite). Therefore, development as a digital television is being advanced at a rapid pace. Among them, the integration of tuners has been promoted, and passive elements such as band-pass filters, RF amplifiers, mixer circuits, etc., which have been realized as external components of semiconductor integrated circuits, are now combined with a PLL circuit which is a digital circuit into one. An LSI integrated on a semiconductor substrate (chip) has also been developed.

[0007]

However, although the integration of tuners has been advanced to some extent as described above, the integration of other functional components necessary for constructing a television receiver is not possible. Was enough. For example, a volume circuit for adjusting the volume of an output sound is still realized by an analog circuit using a bipolar transistor or the like, and the volume is adjusted in an analog manner.

That is, the above-described volume circuit is realized by using, for example, an FM detection circuit. The FM detection circuit includes a phase shift circuit that shifts the phase of the IF signal by 90 degrees at the center frequency, and a multiplication circuit that performs phase detection using the IF signal and the output signal of the phase shift circuit and outputs an FM detection signal. It is comprised including. Then, the F thus configured
The volume was adjusted by passing the IF signal through the M detection circuit and changing the magnitude of the output DC voltage.

Conventionally, the above-mentioned phase shift circuit has been constituted by passive elements such as capacitors and coils, and has been realized as an external component of a semiconductor integrated circuit. Therefore, the number of components has increased, which has been one of the factors that hinder the thinning and miniaturization of the television receiver. In addition, since the number of components is large and the semiconductor substrate on which a tuner or the like is mounted and the printed circuit board on which external components such as a volume circuit are mounted must be separately designed and manufactured, design time and manufacturing time are reduced. There was also a problem that the cost was high.

In addition, since a semiconductor chip on which a tuner or the like is mounted and an external component on which a volume circuit or the like is mounted are manufactured separately, there is a variation in the manufacturing of elements between the semiconductor chip and the external component, resulting in manufacturing. There is also a problem that the performance of a television receiver is not stable.

The present invention has been made in order to solve such a problem, and further aims to further integrate circuits necessary for constituting a radio communication terminal such as a television receiver. It is an object of the present invention to realize a reduction in size and thickness of a device, a reduction in manufacturing cost, and a reduction in design time.

[0012]

A wireless terminal integrated circuit according to the present invention is a wireless terminal integrated circuit in which at least a part of a circuit used for wireless communication is integrated on a semiconductor substrate.
A tuner section that receives a high-frequency signal and performs a predetermined process to output an intermediate frequency signal corresponding to a desired reception frequency, and a volume section that performs level adjustment on the signal processed by the tuner section are the same. It is characterized by being integrated on a semiconductor substrate.

According to another aspect of the present invention, the tuner section and the volume section are both integrated on the same semiconductor substrate by a CMOS circuit. In another aspect of the present invention, the volume section is an electronic volume including a ladder resistor including a plurality of resistors and a switch group including a plurality of switches.

According to another aspect of the present invention, an amplifier for amplifying a signal whose level has been adjusted by the volume section is further integrated on the same semiconductor substrate as the tuner section and the volume section. . Or,
An amplifier for amplifying a signal whose level has been adjusted by the volume section is mounted outside a semiconductor substrate on which the tuner section and the volume section are integrated.

According to another aspect of the present invention, there is provided an integrated circuit for a wireless terminal in which at least a part of a circuit used in wireless communication is integrated on a semiconductor substrate, wherein a predetermined process is performed by receiving a high-frequency signal. A voice-related circuit including a tuner section for outputting an intermediate frequency signal corresponding to a desired reception frequency and a volume section for adjusting the volume of the signal processed by the tuner section is integrated on the same semiconductor substrate. It is characterized by having done.

A television receiver according to the present invention is a television receiver in which at least a part of a circuit used for receiving a television broadcast is integrated on a semiconductor substrate. Integrated by integrating a tuner section that outputs an intermediate frequency signal corresponding to a desired reception frequency by performing the above processing, and a volume section that performs level adjustment on the signal processed by the tuner section on the same semiconductor substrate And a control unit for controlling the entire television receiver including a tuner unit and a volume unit in the integrated circuit, and a bus to which the integrated circuit and the control unit are connected. I do.

In another aspect of the invention, the tuner section and the volume section in the integrated circuit are both CMOs.
It is characterized by being integrated on the same semiconductor substrate by an S circuit. In another aspect of the present invention, the volume section is an electronic volume including a ladder resistor including a plurality of resistors and a switch group including a plurality of switches.

According to another aspect of the present invention, the integrated circuit further includes an amplifier for amplifying the signal whose level has been adjusted by the volume section. Alternatively, an amplifier for amplifying the signal whose level has been adjusted by the volume unit is mounted outside the integrated circuit.

Since the present invention comprises the above technical means, it is possible to integrate not only the tuner section but also at least the tuner section and the volume section into a CMOS structure and to integrate them on one semiconductor substrate. Part 1
Can be combined into chips. In addition, by integrating not only the volume part but also the amplifying part and the like on the same semiconductor substrate by the CMOS structure, almost all of the audio circuits can be integrated into one chip.

According to another feature of the present invention, the amplifying portion, which generates more heat with power consumption, is provided as an external component of the semiconductor chip, thereby suppressing damage to the semiconductor chip or deterioration in performance due to the heat generation. It becomes possible. Further, the semiconductor chip is commonly used irrespective of the size of the television receiver, and only the amplification part of the external component can be used for a large television and a small television.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram illustrating a configuration example of a main part of a television receiver according to the first embodiment. As shown in FIG. 1, the television receiver according to the first embodiment includes an antenna 1 for receiving a television wave, a tuner 2, an intermediate frequency amplifier (IF amplifier) 3, an electronic volume 4, an audio processing circuit 5, Amplifier 6, video processing circuit 7,
It includes a flash memory 11, a RAM 12, a microcomputer (microcomputer) 13, and the like.

The radio wave for television broadcast received by the antenna 1 is input to the tuner 2. The tuner 2 is configured as shown in FIG. 5, and mixes a high-frequency television signal received via the antenna 1 with a signal of a local oscillation frequency controlled according to a set desired reception frequency. To extract an intermediate frequency (IF) signal. The IF signal extracted by the tuner 2 is amplified by the IF amplifier 3. Note that these tuner 2 and IF
The tuner section of the present invention is constituted by the amplifier 3.

The IF signal output from the IF amplifier 3 is subjected to predetermined video signal processing by a video processing circuit 7 for a video, and is converted into a CRT (not shown) as a video signal.
And a display device such as an LCD. On the other hand, the audio is digitally adjusted in volume by the electronic volume 4 and then subjected to predetermined audio signal processing by the audio processing circuit 5. Then, the signal is appropriately amplified by the power amplifier 6 and output to a speaker or the like (not shown).

In the present embodiment, in the television receiver configured as shown in FIG. 1, at least the tuner 2, the IF amplifier 3, the electronic volume 4, the audio processing circuit 5, and the power amplifier 6 which perform at least audio processing. , Are all configured by CMOS circuits, and are mounted on one semiconductor substrate (chip) 10. This semiconductor chip 1
0 and the video processing circuit 7 are connected to the digital bus 14.

The flash memory 11, the RAM 12, and the microcomputer 13 receive digital broadcast waves such as digital satellite broadcasts such as BS and CS, terrestrial digital broadcasts, and cable television broadcasts by the semiconductor chip 10, and transmit the digital broadcast waves to a display device or a speaker. It is provided to perform a series of controls for a process of outputting video and audio. That is,
The flash memory 11, RAM 12, and microcomputer 13 are also connected to the digital bus 14, and control the operations of the semiconductor chip 10 and the video processing circuit 7 described above.

FIG. 2 is a circuit diagram showing a configuration example of the electronic volume 4. As shown in FIG. 2, the electronic volume 4 is a digital circuit composed of a ladder resistor 21 composed of a plurality of resistors R1, R2,... Rn and a switch group 22 composed of a plurality of switches SW1, SW2,. is there. A plurality of switches SW constituting the switch group 22
1, SW2,..., SWn are, for example, constituted by elements having a CMOS structure called transmission gates, respectively.

The switches SW1, S
W2,... SWn ON / OFF is determined by CPU or MP
U and the like, which are controlled according to a control signal given from the microcomputer 13 of FIG.
The sound volume is adjusted digitally depending on which switch is turned on.

As described above, in the present embodiment, F
An electronic volume 4 having a CMOS structure is provided instead of an analog volume having a capacitor, a coil, and the like as in the M detection circuit. In addition to the tuner 2 and the IF amplifier 3, the electronic volume 4, the audio processing circuit 5, and the power amplifier 6 are all integrated on a single semiconductor chip 10 as a CMOS structure. The device can be integrated into a chip, and the number of components can be reduced, so that the device can be further reduced in size and thickness.

Also, when designing and manufacturing an audio system circuit,
Unlike the conventional case, there is no need to separately design and manufacture a semiconductor chip and its external components. Since the semiconductor chip and the external parts can be collectively performed on one semiconductor chip 10, the design time can be significantly reduced, and the manufacturing time can be greatly reduced. Costs can be significantly reduced. In addition, since variations in manufacturing elements in one semiconductor chip 10 can be suppressed, variations in performance of the television receiver can be suppressed.

Further, since the volume of the output sound can be digitally adjusted, not only can the microcomputer 13 select the tuner 2 (select the desired reception frequency), but also the volume can be adjusted by the microcomputer 13. It can be carried out. In the case where the volume is adjusted analogously as in the related art, the output level may change due to an external factor such as temperature.
By adopting the OS structure, the volume of the output sound can be digitally adjusted, and the volume can be controlled stably.

Since the volume can be adjusted by the microcomputer 13, the volume can be easily adjusted by remote operation using a remote controller (not shown). Further, according to the present embodiment, the tuner 2, the IF amplifier 3, the electronic volume 4
Since the common digital bus 14 can be used in the audio processing circuit 5 (data is distributed inside the chip), the circuit configuration can be further simplified, and the size of the device can be further reduced. it can.

Next, a second embodiment of the present invention will be described. FIG. 3 is a diagram illustrating a configuration example of a main part of a television receiver according to the second embodiment. In FIG. 3, components denoted by the same reference numerals as those shown in FIG. 1 have the same functions.

As shown in FIG. 3, the television receiver according to the second embodiment also includes an antenna 1, a tuner 2, an IF amplifier 3, an electronic volume 4, an audio processing circuit 5, and a power amplifier 6 for receiving a television wave. , Video processing circuit 7,
It is configured to include a flash memory 11, a RAM 12, a microcomputer 13, and the like.

However, in the second embodiment, the tuner 2, the IF amplifier 3, the electronic volume 4, and the audio system processing circuit 5 of the audio system circuit for performing audio processing
It is configured by an OS circuit and mounted on one semiconductor chip 30. In the present embodiment, at least the power amplifier 6 is realized as an external component to the semiconductor chip 30.

In this embodiment, the tuner 2 and the IF
In addition to the amplifier 3, the electronic volume 4 and the audio processing circuit 5 also have a CMOS structure and are mounted on one semiconductor chip 30, so that the number of components can be reduced as compared with the related art, and the size of the device can be reduced.・ Thinning can be realized. In addition, effects similar to the effects described in the first embodiment can be achieved in the present embodiment.

Furthermore, in the present embodiment, only the power amplifier 6, which generates more heat with power consumption, is an external component of the semiconductor chip 30, so that damage to the semiconductor chip 30 or deterioration in performance due to heat generation is suppressed. be able to. In addition, it is necessary to use different power amplifiers 6 having different amplification capabilities for a large television receiver having a large display screen and a small television receiver having a small display screen. Can be used irrespective of the size of the television, and only the power amplifier 6 can be used separately for the large television and the small television, which is very efficient in design or manufacture.

In the example of FIG. 3, the tuner 2, the IF amplifier 3, the electronic volume 4, and the audio processing circuit 5 are connected to one.
Tuners 2, I
The F amplifier 3 and the electronic volume 4 may be mounted on a single semiconductor chip, and the remaining audio processing circuit 5 and power amplifier 6 may be provided as external components.

In the examples of FIGS. 1 and 3,
A digital demodulation circuit between the IF amplifier 3 and the electronic volume 4, for example, PSK (Phase
A PSK demodulation circuit or a QAM (Quadrature Amplitude Modulation) demodulation circuit for performing a quadrature amplitude demodulation process is provided.
The demodulation circuit may be mounted on the same semiconductor chip. Further, the present invention can be applied to a television receiver that receives digital broadcasts and a television receiver that receives analog broadcasts.

In each of the above embodiments, the case where the wireless terminal integrated circuit (semiconductor chip) of the present invention is applied to a television receiver has been described. However, the present invention is not limited to this. The present invention can be similarly applied to any device that receives at least an audio signal through communication, performs predetermined processing, and outputs the processed signal. For example, a wireless communication terminal such as a mobile phone or a PHS having an RF filter or the like, an AM
The present invention can be applied to a radio receiver for broadcasting, FM broadcasting, short-wave broadcasting, and the like. In each of the above embodiments,
Although the example in which the semiconductor chip is configured by the CMOS circuit has been described, the semiconductor chip may be configured by a Bi-CMOS circuit.

In addition, each of the above-described embodiments is merely an example of the embodiment for carrying out the present invention, and the technical scope of the present invention should not be interpreted in a limited manner. It must not be. That is, the present invention can be embodied in various forms without departing from the spirit or main features thereof.

[0041]

As described above in detail, according to the present invention, at least the volume section is provided with the CM in addition to the tuner section.
Since the OS structure is adopted and integrated on one semiconductor substrate, more parts of the audio system circuit can be integrated into one chip. Further, since not only the volume section but also the amplification section and the like have a CMOS structure and are integrated on the same semiconductor substrate, almost all of the audio circuits can be integrated into one chip.

As a result, the number of parts can be reduced and the size and thickness of the television receiver can be further reduced. Also, when designing and manufacturing an audio system circuit, it is not necessary to separately design and manufacture the semiconductor chip and its external components, and the design can be performed on one semiconductor chip. It is possible to shorten the production time and to greatly reduce the production cost. Also,
Since the manufacturing variation of the elements in one semiconductor chip is suppressed, the stability of the performance of the television receiver can be improved.

Further, since the volume of the output sound can be digitally adjusted, the volume can be adjusted by the microcomputer in addition to tuning in the tuner section (selection of the desired reception frequency), and the volume can be stabilized. Control. Further, the volume can be easily adjusted by remote control using a remote controller. Further, a common digital bus can be used in various functional circuit units in the integrated chip, so that the circuit configuration can be further simplified and the size of the device can be further reduced.

According to another feature of the present invention, since the amplifying portion that generates more heat with power consumption is an external component of the semiconductor chip, damage to the semiconductor chip or deterioration in performance due to the heat generation can be suppressed. Can be. In addition, the same semiconductor chip can be used in common for both large and small size television receivers, and only the amplifying part of external components can be used separately for large and small televisions, thus improving design or manufacturing efficiency. Can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration example of a main part of a television receiver according to a first embodiment.

FIG. 2 is a diagram illustrating a configuration example of an electronic volume.

FIG. 3 is a diagram illustrating a configuration example of a main part of a television receiver according to a second embodiment.

FIG. 4 is a diagram illustrating a general configuration example of a conventional television receiver.

FIG. 5 is a diagram illustrating a configuration example of a tuner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Antenna 2 Tuner 3 IF amplifier 4 Electronic volume 5 Audio processing circuit 6 Power amplifier 7 Video processing circuit 10 Semiconductor chip 11 Flash memory 12 RAM 13 Microcomputer 14 Digital bus 21 Ladder resistance 22 Switch group 30 Semiconductor chip

 ──────────────────────────────────────────────────の Continued on the front page F term (reference) 5C025 AA24 AA25 AA29 BA27 5C026 DA05 5J098 AA03 AA11 AC05 AC10 AC20 AC27 AD14 AD26 EA01 EA09 5K016 CB09 CB12 5K020 AA02 BB09 DD15 EE04 GG01 LL01 MM11

Claims (11)

[Claims] An integrated circuit for a wireless terminal in which at least a part of a circuit used for wireless communication is integrated on a semiconductor substrate, and which receives a high-frequency signal and performs a predetermined process to correspond to a desired reception frequency. An integrated circuit for a wireless terminal, wherein a tuner section for outputting an intermediate frequency signal and a volume section for adjusting a level of a signal processed by the tuner section are integrated on the same semiconductor substrate. 2. The integrated circuit for a wireless terminal according to claim 1, wherein both the tuner section and the volume section are integrated on the same semiconductor substrate by a CMOS circuit. 3. The integrated radio terminal according to claim 2, wherein the volume section is an electronic volume composed of a ladder resistor composed of a plurality of resistors and a switch group composed of a plurality of switches. circuit. 4. An apparatus according to claim 1, wherein an amplifier for amplifying the signal whose level has been adjusted by said volume section is further integrated on the same semiconductor substrate as said tuner section and said volume section. The wireless terminal integrated circuit according to claim 1. 5. An amplifying section for amplifying a signal whose level has been adjusted by said volume section is mounted outside a semiconductor substrate on which said tuner section and said volume section are integrated. 4. The integrated circuit for a wireless terminal according to claim 3. 6. An integrated circuit for a wireless terminal in which at least a part of a circuit used in wireless communication is integrated on a semiconductor substrate, wherein the integrated circuit for a wireless terminal receives a high-frequency signal and performs predetermined processing to correspond to a desired reception frequency. And a sound circuit including a tuner section for outputting the adjusted intermediate frequency signal and a volume section for adjusting the volume of the signal processed by the tuner section, on a same semiconductor substrate. Integrated circuit for wireless terminals. 7. A television receiver in which at least a part of a circuit used for receiving a television broadcast is integrated on a semiconductor substrate. The television receiver receives a high frequency signal and performs a predetermined process to obtain a desired reception frequency. An integrated circuit in which a tuner section for outputting an intermediate frequency signal corresponding to the above, and a volume section for adjusting the level of the signal processed by the tuner section are integrated on the same semiconductor substrate; and a tuner in the integrated circuit. A television receiver comprising: a control unit that controls the entire television receiver including a unit and a volume unit; and a bus that connects the integrated circuit and the control unit. 8. The television receiver according to claim 7, wherein both the tuner section and the volume section in the integrated circuit are integrated on the same semiconductor substrate by a CMOS circuit. 9. The television receiver according to claim 8, wherein the volume section is an electronic volume composed of a ladder resistor composed of a plurality of resistors and a switch group composed of a plurality of switches. . 10. The integrated circuit according to claim 7, wherein the integrated circuit further integrates an amplifying unit that amplifies a signal whose level has been adjusted by the volume unit. Television receiver. 11. The television according to claim 7, wherein an amplifier for amplifying the signal whose level has been adjusted by the volume unit is mounted outside the integrated circuit. Receiver.