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1. 发明专利

JPH06141354A SUBSCRIBER CIRCUIT 失效
公开(公告)号：JPH06141354A
公开(公告)日：1994-05-20
申请号：JP28469192
申请日：1992-10-22
申请人： HITACHI LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： ABE YOSHITAKA , ARITA KAORU , ISHIZAWA AKIRA
IPC分类号： H04M19/00 , H04Q1/56 , H04Q3/42
摘要： PURPOSE:To reduce power consumption by keeping a transmission gain of the subscriber circuit constant independently of the length of a subscriber line and feeding power to a telephone set terminal with a constant current. CONSTITUTION:The subscriber circuit 9 connecting to a terminal equipment via a subscriber line 2 and receiving/outputting a signal is provided with a constant current feeding circuit 3 applying DC constant current feeding and a termination circuit 7 placed between signal input and a signal output to decide the impedance of the subscriber circuit and the termination circuit 7 variably sets the transfer coefficient of itself so that the impedance being the sum of that of the subscriber line and that of the subscriber circuit is a predetermined impedance.

2. 发明专利

JP2001197225A SUBSCRIBER CIRCUIT 失效
公开(公告)号：JP2001197225A
公开(公告)日：2001-07-19
申请号：JP2000006166
申请日：2000-01-11
申请人： HITACHI LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： OTA SHINYA , ARITA KAORU , AKIYAMA KAZUHIKO
IPC分类号： H04M19/00 , H04Q3/42
摘要： PROBLEM TO BE SOLVED: To perform normal power supply and reversed power supply to a subscriber line with an economical configuration and with power consumption reduced. SOLUTION: This circuit consists of a reversing switch 2 and a common power supply 3, and the economically configured common power supply 3 performs normal power supply and reversed power supply to the subscriber terminal 1 through the switch formed by connecting a field-effect transistor for normal power supply that is turned on only in a normal power supply mode and a field-effect transistor for reversed power supply that is turned on only in a reversed power supply mode as a reversed polarity state to each other and also as a confounded state.

3. 发明专利

JP2000083263A EXCHANGE 失效
公开(公告)号：JP2000083263A
公开(公告)日：2000-03-21
申请号：JP25907399
申请日：1999-09-13
申请人： HITACHI LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： ABE YOSHITAKA , ARITA KAORU , ISHIZAWA AKIRA
IPC分类号： H04M19/00 , H04Q3/42
摘要： PROBLEM TO BE SOLVED: To reduce power consumption by keeping a transmission gain of a subscriber circuit constant independently of a length of a subscriber line so as to feed a constant current to a telephone terminal. SOLUTION: A subscriber circuit 9 that connects with a terminal via a subscriber line 2 and that receives/outputs a signal has a constant current feeding circuit 3 that feeds DC power by a constant current, and also it has a termination circuit 7 that is provided between an input and an output of the signal and that decides an impedance of a subscriber circuit. Then the termination circuit 7 variably sets a transfer coefficient of this termination circuit so that the combined impedance of the subscriber line and the subscriber circuit is a predetermined one.

4. 发明专利

JPS6417591A LINE CURRENT DETECTION CIRCUIT 失效
公开(公告)号：JPS6417591A
公开(公告)日：1989-01-20
申请号：JP17280787
申请日：1987-07-13
申请人： HITACHI LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： ARITA KAORU , KITANO JUNJIRO , INABE YASUNOBU
IPC分类号： H04Q3/42
摘要： PURPOSE:To detect a line current with high accuracy by providing a transistor to correct the voltage between the base and the emitter of a voltage-current conversion transistor in a voltage-current conversion circuit. CONSTITUTION:An A-line current IA and a B-line current IB are converted to voltages by resistors RA1, RB1 respectively, and thus voltages VA, VB are generated. The voltage-current converter 1 on the A-side outputs an output current IA2 proportionate to the input voltage VA, while the voltage-current converter 2 on the B-side outputs an output current IB2 proportionate to the input voltage VB. A detection output part 3 for sum current outputs an output voltage VOUT proportionate to the sum current I21 of the currents IA2, IB2. In this case, in the converter 1, the TRQ3 is provided for correcting the VBE of the transistors TRQ4, Q8 for voltage-current conversion, and by correcting the VBE of the TRQ4, Q8, a voltage-current conversion difference is eliminated. In such a way, a highly accurate detection of a current can be executed.

5. 发明专利

JPS62213463A CONSTANT VOLTAGE CONTROL CIRCUIT 失效
公开(公告)号：JPS62213463A
公开(公告)日：1987-09-19
申请号：JP5483586
申请日：1986-03-14
申请人： HITACHI LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： ARITA KAORU , KITANO JUNJIRO , HAYASHI TOSHIO , KIMURA TADAKATSU
IPC分类号： H04M19/00 , G05F1/56
摘要： PURPOSE:To attain the low power consumption and high accuracy of a constant voltage supply control by constituting the feedback loop of constant voltage supply control by a constant voltage control circuit and an existing current mirror. CONSTITUTION:A differential amplifier OP1 in a constant voltage control circuit 5 detects a voltage drop v1 of a low pass filter 4 generated by a current i1 flowing to a resistor R1 and a transistor (TR) ThQ1 and controls a current i2 so as to make the voltage v2 caused by the current i2 flowing to TRs Q3, Q2 and a resistor R2 equal to the voltage v1. Then a voltage drop of the lowpass filter 4 is subjected to voltage/current conversion and fed back to the input of a current mirror A1 to realize the constant voltage feeding characteristic. Since the feedback loop of constant voltage feeding control is constituted by the constant voltage control circuit 5 and the current mirror A1, the circuit acts by a low voltage system and low power consumption is attained.

6. 发明专利

JPH07307815A FEEDER 失效
公开(公告)号：JPH07307815A
公开(公告)日：1995-11-21
申请号：JP9868694
申请日：1994-05-12
申请人： HITACHI LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： ARITA KAORU , KITANO JUNJIRO , YAMANO SEIICHI
IPC分类号： H04M19/00
摘要： PURPOSE:To obtain a feeder capable of being integrated into a semiconductor integrated circuit in which crosstalk to adjacent subscriber lines is suppressed at polarity inversion and the size of the feeder is made small as a whole like a chip. CONSTITUTION:The flowing direction of a speech current from a current feeder circuit including transistors(TRs) Q1, Q2 to subscriber lines L1, L2 depends on the switching of PNPN switches Sl-S4. In the case of the switching (polarity inversion), after the speech current from the current feeder circuit is once transited to zero gradually, the polarity is inverted while outputs from the TRs Q1, Q2 are interrupted, and the current gradually restores to a state in the non-polarity inversion from zero. When the PNPN switches S1-S4 are adopted for the polarity inversion switches, the feeder is formed with a small chip and the entire feeder is integrated into an integrated circuit.

7. 发明专利

JPH0319409A VOLTAGE CURRENT CONVERSIONAL CIRCUIT 失效
公开(公告)号：JPH0319409A
公开(公告)日：1991-01-28
申请号：JP15236289
申请日：1989-06-16
申请人： HITACHI LTD , HITACHI MICROCUMPUTER ENG
发明人： ARITA KAORU , KITANO JUNJIRO
IPC分类号： H03F1/30
摘要： PURPOSE:To improve the power supply noise characteristic by connecting one terminal of phase compensation capacitor to a collector of a transistor(TR), the other terminal to an equivalent ground and connecting an output of a current controlled current source outputting a current proportional to a current flowing to the phase compensation capacitor to a base of the TR so as to apply phase compensation. CONSTITUTION:The circuit consists of an output transistor(TR) Q1, an output current sensing resistor Re, a transconductor amplifier 8, a phase compensation capacitor C, a power supply VEE and a current controlled current source 9. Then the feedback by the phase compensation capacitance C is injected to a base of the output TR Q1 via the current controlled current source 9. Then the current controlled current source 9 outputs a current ic2 proportional to a current ic1 flowing to an input terminal 6, and an input terminal 6 is connected to ground equivalent in terms of AC to make it equivalent that a mirror capacitance CM is connected between an output terminal 1 and ground. Thus, noise of the power supply VEE is prevented from flowing to the output via the mirror capacitance CM and the power noise characteristic is improved.

8. 发明专利

JPH01248779A PICTURE SIGNAL SYSTEM 失效
公开(公告)号：JPH01248779A
公开(公告)日：1989-10-04
申请号：JP7438188
申请日：1988-03-30
申请人： HITACHI LTD , HITACHI MICROCUMPUTER ENG
发明人： ARITA KAORU , KITANO JUNJIRO
IPC分类号： H04N5/928 , H04N5/92 , H04N7/04 , H04N7/045
摘要： PURPOSE:To multiplex an audio signal onto a picture signal while minimizing missing of video information by using the system where the time width such as pulse amplitude modulation is a short time. CONSTITUTION:A 2-input 1-output selector 20 selects either a video signal 61 or an audio signal 63 by using control signals 62, 64. Let the waveform of the audio signal 63 be (e), then a pulse amplitude modulation signal (f) is inserted to the video signal 61 by the control signal 64 to form a waveform (g). Then a multiplex signal 70 between the video signal and the audio signal is recorded from a signal line 4 as a video signal input to a VTR. A control signal 67 is generated similarly as the preceding control signal 64 at reproduction to form a sampling pulse. Thus, the audio signal is multiplexed on the video signal to attain recording and reproduction.

9. 发明专利

JP2003347906A comparator 有权
标题翻译：比较器
公开(公告)号：JP2003347906A
公开(公告)日：2003-12-05
申请号：JP2002154837
申请日：2002-05-29
申请人： Hitachi Electronics Eng Co Ltd , Hitachi Ltd , 日立電子エンジニアリング株式会社 , 株式会社日立製作所
发明人： IMAGAWA KENGO , NAKAJO TOKUO , ARITA KAORU , UMEMURA YOSHIHARU , IMANARI MASAHIRO
IPC分类号： G01R19/165 , G01R31/28 , H03F3/45 , H03K5/08 , H03K5/24
CPC分类号： H03F3/45152 , H03F2203/45472 , H03F2203/45658 , H03F2203/45681 , H03K5/08 , H03K5/2409
摘要： PROBLEM TO BE SOLVED: To provide a comparator circuit operable at high speed in which an input voltage range is made wider than that of a differential amplifier type comparator. SOLUTION: The comparator has a transistor pair normally conductive and is provided with: a switch means comprising a diode pair for switching a current path depending on the magnitude of a voltage level between an input signal and a comparison voltage; and a means for converting a current into a voltage level, which are placed between emitter terminals of the transistor pair. COPYRIGHT: (C)2004,JPO

10. 发明专利

JPH04305718A CONSTANT VOLTAGE CIRCUIT 失效
公开(公告)号：JPH04305718A
公开(公告)日：1992-10-28
申请号：JP7080391
申请日：1991-04-03
申请人： HITACHI LTD , HITACHI MICOM SYST KK
发明人： ARITA KAORU , ABE YOSHITAKA
IPC分类号： G05F3/26
摘要： PURPOSE:To obtain a constant voltage circuit operable even in a state that an input power supply voltage is approximate to an output voltage, stable against load variation and small number of elements. CONSTITUTION:An output transistor(TR) Q11 for controlling a bias current IZ and an output current I0 to a reference voltage source (Zenner diode Z11), a detecting circuit for detecting the bias current IZ flowing into the reference voltage source Z11 and a constant current source I1 for outputting a fixed current are used and the output TR Q11 is controlled so that a detected current I2 becomes the same as the current of the constant current source I1, i.e., the bias current IZ is fixed. Consequently the constant voltage circuit stable for load variation and capable of being driven until the input voltage approaches the output voltage can be obtained by the small number of elements.

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