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1. 发明专利

JPH01105616A OPTICALLY COUPLED D-A CONVERTER 失效
公开(公告)号：JPH01105616A
公开(公告)日：1989-04-24
申请号：JP26156887
申请日：1987-10-19
申请人： HITACHI LTD , HITACHI VIDEO ENG
发明人： AKAGI TAKATOSHI
IPC分类号： H03M1/74
摘要： PURPOSE:To facilitate the adjustment of a resistor for the fine adjustment of the weighting of a digital signal, and the setting of a resistance value by weighting the digital signal by changing a distance between a light emitting part and a light receiving part for every bit. CONSTITUTION:The digital signal, inputted from terminals 91-94, passes through resistors 31-34 and emits light after being electricity-light converted by the light emitting parts 21-24. The emitted light passes through transparent molded material 51, and reaches the light receiving part, and is light-electricity converted, and outputs an analog signal from the terminal 81, and D-A conversion is completed. The distance between the light receiving part 11 and the light emitting parts 21-24 is changed previously in conformity with a number of bits, and the signal is weighted. Besides, the resistors 31-34 are adjusted by trimming, etc., so as to make the precision of the D-A conversion high. In this case, since the resistance values inserted in series with the light emitting parts come to be approximately equal to each other, the fine adjustment of the resistor and the setting of the resistance value come to be easy.

2. 发明专利

JPH0481823A FILTER COMBINED WITH SURFACE ACOUSTIC WAVE RESONATOR 失效
公开(公告)号：JPH0481823A
公开(公告)日：1992-03-16
申请号：JP19496390
申请日：1990-07-25
申请人： HITACHI LTD , HITACHI VIDEO ENG
发明人： SHIBAGAKI NOBUHIKO , HIKITA MITSUTAKA , TABUCHI TOYOJI , ISOBE ATSUSHI , KIKUKAWA ATSUSHI , SUZUKI KAZUTOSHI , AKAGI TAKATOSHI
IPC分类号： H03H9/145 , G02F1/11 , G02F1/23 , H03H9/25 , H03H9/64
摘要： PURPOSE:To provide the filter of a low loss and high attenuation rate by most adequately setting the relative various size relation of the electrical impedances of the surface acoustic wave resonators of a series arm and parallel arm. CONSTITUTION:The total sum of the reciprocals of the product of the electrode pair number and the electrode finger crossing width of the surface acoustic wave resonator connected to the series arm with respect to a signal route, i.e. the electrical impedance of the series arm is set at >=2.0 times and

3. 发明专利

JPH04132409A SURFACE ACOUSTIC WAVE RESONATOR 失效
公开(公告)号：JPH04132409A
公开(公告)日：1992-05-06
申请号：JP25197590
申请日：1990-09-25
申请人： HITACHI LTD , HITACHI VIDEO ENG
发明人： TABUCHI TOYOJI , HIKITA MITSUTAKA , SHIBAGAKI NOBUHIKO , KIKUKAWA ATSUSHI , AKAGI TAKATOSHI , SUZUKI KAZUTOSHI
IPC分类号： H03H9/145 , H03H9/64
摘要： PURPOSE:To suppress the degradation in the characteristic between attenuation poles by forming a multi-pair transducer of one-aperture surface acoustic wave resonator with the combination of >= two regions with different electrode pitches. CONSTITUTION:This surface acoustic wave transducer consists of plural regions and each region is arranged with plural interdigital electrode pairs continuously at the same pitch and pitches P1, P2 of the interdigital electrode pairs of the adjacent regions are made different. That is, the transducer consists of regions (5-1)-(5-2) in which the electrode finger pitch of the transducer is P1 and regions (6-1)-(6-3) in which the electrode finger pitch of the transducer is P2. In this case, the resonance characteristic of the one-aperture surface acoustic wave resonator in which the multi-pair transducer consists of plural regions whose electrode finger pitch differs has plural attenuation poles corresponding to the plural electrode pitches. Thus, since the resonator composite filter composed of plural one-aperture surface acoustic wave resonators has attenuation poles more then the total number of the one-aperture surface acoustic wave resonators, the frequency difference between the attenuation poles is set small and the degradation in the characteristic between the attenuation poles is suppressed.

4. 发明专利

JPH0472950A RADIO TELEPHONE SET 失效
公开(公告)号：JPH0472950A
公开(公告)日：1992-03-06
申请号：JP18397290
申请日：1990-07-13
申请人： HITACHI LTD , HITACHI VIDEO ENG
发明人： KUROSAWA KAZUHITO , HIKITA MITSUTAKA , TABUCHI TOYOJI , SHIBAGAKI NOBUHIKO , SUZUKI KAZUTOSHI , OTSUKA TOSHIHIRO , AKAGI TAKATOSHI
IPC分类号： H04M1/02 , H01Q1/44
摘要： PURPOSE:To make the radio telephone set main body small to the utmost by adopting the structure for a microphone support member so as to be drawn out of a main body of the radio telephone set and using the drawn-out part as an antenna. CONSTITUTION:An antenna 6 is suspended and projected from a bottom face 1a and a microphone 5 is fitted to the tip of the antenna 6. In the case of talking, a speaker 2 built in the main body 1 is in contact with an ear and the microphone 5 at the tip of the antenna 6 is placed close to a mouth. Thus, even when the size of the main body 1 is made small, a sufficient distance is ensured between the speaker 2 and the microphone 5 and talking quality is kept constant. Moreover, since the support member of the microphone 5 is used as an antenna, it is not required to provide the antenna separately from the support member of the microphone.

5. 发明专利

JPH04253414A BRANCH FILTER USING SURFACE ACOUSTIC WAVE RESONATOR COMPOSITE FILTER 失效
公开(公告)号：JPH04253414A
公开(公告)日：1992-09-09
申请号：JP961591
申请日：1991-01-30
申请人： HITACHI LTD , HITACHI VIDEO & INF SYST
发明人： TABUCHI TOYOJI , HIKITA MITSUTAKA , SHIBAGAKI NOBUHIKO , AKAGI TAKATOSHI , SUZUKI KAZUTOSHI
IPC分类号： H03H9/25 , H03H9/64
摘要： PURPOSE:To reduce energy consumption by deciding the arrangement and connecting method of one-opening surface acoustic wave resonators so that an impedance characteristic on the side or a common terminal can have reactivi ty. CONSTITUTION:With a single antenna 1 as the common terminal, a filter 2 for reception and a filter 3 for transmission are parallelly connected. In this case, the four one-opening surface acoustic wave resonators composed of electrodes 4-1-4-6 or the like and gap capacitors composed of electrode patterns 5-1 and 5-2 are provided and formed on a piezoelectric substrate 7, which can propagate surface acoustic waves, so as to be used as the filter 3 for transmission. Further, acoustic absorbing materials 6-1-6-6 for absorbing the surface acoustic waves and inductances 8-1-8-4 for matching an outside circuit are provided. Moreover, each one-opening surface acoustic wave resonator is composed of an equivalent inductance 11-1, equivalent capacitor 12-1 and electrostatic capacitor 13-1.

6. 发明专利

JPH06236815A HIGH-FREQUENCY CIRCUIT DEVICE AND RADIO APPARATUS 失效
公开(公告)号：JPH06236815A
公开(公告)日：1994-08-23
申请号：JP22685993
申请日：1993-09-13
申请人： HITACHI LTD , HITACHI VIDEO & INF SYST
发明人： SHIBAGAKI NOBUHIKO , HIKITA MITSUTAKA , TABUCHI TOYOJI , AKAGI TAKATOSHI , WAKAMORI SATOSHI , MATSUMOTO TOMOZO
IPC分类号： H01F27/00 , H03H9/145 , H03H9/25 , H04B1/08 , H04B1/38 , H04B1/3822 , H05K1/18 , H01F15/00
摘要： PURPOSE:To provide a high-frequency circuit device wherein it is effective to make an apparatus utilizing the high-frequency circuit device such as a radio apparatus or the like small-sized and its high-frequency characteristic is good. CONSTITUTION:In a high-frequency circuit device which is provided with a package 7 having an airtight space used to house a high-frequency circuit element 8, the high-frequency circuit element 8 is fixed and bonded, via a conductor pattern, to the surface of a board 1 constituting the package 7 and a winding inductance 11 is installed in a hole made in the rear of the board 1.

7. 发明专利

JPH05251987A 失效
公开(公告)号：JPH05251987A
公开(公告)日：1993-09-28
申请号：JP4669192
申请日：1992-03-04
申请人： HITACHI LTD , HITACHI VIDEO & INF SYST
发明人： TABUCHI TOYOJI , HIKITA MITSUTAKA , SHIBAGAKI NOBUHIKO , AKAGI TAKATOSHI , WAKAMORI SATOSHI
IPC分类号： H03H7/38 , H03H9/64
摘要： PURPOSE:To provide a communication use high performance filter having a low loss and a broad band characteristic by solving a problem of impedance mis-matching of the surface acoustic wave resonator composite filter comprising plural surface acoustic wave resonators. CONSTITUTION:An impedance matching circuit 8 including inductive elements 10-1-10-4 is inserted to an electric connecting point in the inside of the surface acoustic wave resonator composite filter. Number of the inserted matching circuits 8 or their location is optionally selected. The selection is optimized by taking the relation of the filter configuration or its characteristic and specification into account. A can type or surface mount type package or the like with a connection terminal to the matching circuit 8 thereto is used for the mount of the surface acoustic wave resonator composite filter having the internal matching circuit 8. Since the matching state in the inside of the filter is improved as a result, the communication use high performance filter having a low loss and a broad band characteristic is realized.

8. 发明专利

JPH0522074A SURFACE ACOUSTIC WAVE RESONATOR, SURFACE ACOUSTIC WAVE RESONATOR COMPOSITE FILTER AND RADIO TRANSMITTER/ RECEIVER 失效
公开(公告)号：JPH0522074A
公开(公告)日：1993-01-29
申请号：JP17123691
申请日：1991-07-11
申请人： HITACHI LTD , HITACHI VIDEO & INF SYST
发明人： TABUCHI TOYOJI , HIKITA MITSUTAKA , SHIBAGAKI NOBUHIKO , AKAGI TAKATOSHI
IPC分类号： H03H9/145 , H03H9/64 , H04B1/40
摘要： PURPOSE:To obtain the surface acoustic wave resonator which can arbitrarily turn a resonance characteristic to a narrow band by electrically parallelly connecting a gap capacitor formed with a thin film electrode on a piezoelectric substrate to the surface acoustic wave resonator. CONSTITUTION:The gap capacitor composed of plane electrodes 19-1 and 19-2 formed on the same piezoelectric substrata as the surface acoustic wave resonator composed of many pairs of interlaced electrodes are electrically parallelly connected by electric wirings 20-1 and 20-2. In this case, the thin film electrode formed on the piezoelectric substrate similarly to the gap capacitor or the wire of Al or the like is used for the electric wirings 20-1 and 20-2. Namely, by electrically parallelly connecting the gap capacitor to the surface acoustic wave resonator, the parallel capacity of the resonator is increased. Therefore, a capacity ratio applied by a ratio between this capacity and the equalizing capacity of the resonator is enlarged, and the resonance characteristic of the narrow band can be realized.

9. 发明专利

JPH04301909A SIGNAL DISTRIBUTOR 失效
公开(公告)号：JPH04301909A
公开(公告)日：1992-10-26
申请号：JP6596791
申请日：1991-03-29
申请人： HITACHI LTD , HITACHI FERRITE LTD , HITACHI VIDEO & INF SYST
发明人： SUZUKI KAZUTOSHI , HIKITA MITSUTAKA , ISHIDA YOSHIKATSU , AKAGI TAKATOSHI , TANAKA SATOSHI
IPC分类号： H03H7/48 , H01P5/16 , H03H7/21
摘要： PURPOSE:To constitute and miniaturize the signal distributor without using any microstrip lines. CONSTITUTION:The twisted lines of insulated cover lines 6 and 6A connected to an input terminal 1 are divided, the lines 6 and 6A are wound around a troidal core 5 more than once from mutually reverse directions, insulated cover line end parts 6-1 and 6A-1 are connected to the input terminal 1, an insulated cover line end part 6-2 is connected to an output terminal 4, and an end part 6A-2 is connected to an output terminal 3. Three insulated cover lines 7, 7A and 7B are twisted and wound around the troidal core more than once, insulated cover line end parts 7-1, 7A-1, 7B-1, 7-2, 7A-2 and 7B-2 are twisted once outside the troidal core, the 7-1 is connected to the output terminal 3, the 7B-1 is connected to an input terminal 2, the 7A-1 is connected to the output terminal 4, and the 7A-2, 7-2 and 7B-2 are connected to a ground conductor. On the other hand, when a signal is inputted to one input terminal, the signals of the mutually same phase component are outputted to the output terminals and when a signal is inputted to the other input terminal, the signals of mutually reverse phase components are outputted to the output terminals.

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