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11. 发明专利

JPS63302761A DC-DC CONVERTER 失效
公开(公告)号：JPS63302761A
公开(公告)日：1988-12-09
申请号：JP13869187
申请日：1987-06-02
申请人： HITACHI LTD
发明人： KONO NAOFUMI
IPC分类号： H02M3/335
摘要： PURPOSE:To suppress the generation of a leakage inductance, by fitting a first and a second capacitors on a space between the connecting points of the positive and negative poles of a DC power source and a first and a second transformers. CONSTITUTION:A DC-DC converter is provided with a DC power source Vi, a first-a second switching elements Tr1-Tr2, and a first-a second transformers T1-T2. In this case, to a space between the negative pole of the first transformer T1 and the positive pole of the DC power source Vi, and to a space between the positive pole of the second transformer T2 and the negative pole of the DC power source Vi, the same capacitors C1-C2 are respectively connected. By the capacitors C1-C2, the voltage of the DC power source Vi applied to both the transformers T1-T2 is divided. Then, the rectification or the like of the secondary current of the transformers T1-T2 is performed, and the output of DC output voltage V0 is generated. As a result, the ratio of a primary winding to a secondary winding can be suppressed to be diminished, and the generation of a leakage inductance can be suppressed.

12. 发明专利

JPH09149643A DC POWER SUPPLY APPARATUS 失效
公开(公告)号：JPH09149643A
公开(公告)日：1997-06-06
申请号：JP30449395
申请日：1995-11-22
申请人： HITACHI LTD , HITACHI INFORMATION TECHNOLOGY
发明人： SHIMA HIROSHI , OKAWA HIROSHI , KONO NAOFUMI
IPC分类号： H02M7/06 , H02M7/10
摘要： PROBLEM TO BE SOLVED: To utilize various AC input voltages with automatic discrimination by a method wherein an approximately constant DC voltage is supplied to a load connected to a main circuit regardless of the connection of a stepdown transformer. SOLUTION: When the voltage of a commercial power supply 1 is AC 100V, a voltage which is stepped down by a stepdown transformer 2 and rectified and smoothed is applied to voltage dividing resistors 10 and 11, a shunt regulator 18 is turned on in accordance with a ratio between the divided voltages, a control transistor 29 is turned on, a relay contact 23b is closed and, in the positive half cycle period of the AC input of the main circuit, a smoothing capacitor 4 is charged and, in the negative half cycle period, a smoothing capacitor 5 is charged. When the voltage of the commercial power supply 1 is AC 200V, as the rectified and smoothed voltage is doubled, the shunt regulator 18 is turned off, the control transistor 29 is turned off, the relay contact 23b is opened and the smoothing capacitors 4 and 5 which are connected in series are charged. In both the cases, the voltage is full-wave rectified by a load 7 in parallel connection to obtain a required voltage. As a result, a various AC input voltage can be utilized with automatic discrimination.

13. 发明专利

JPH0379949B2 失效
公开(公告)号：JPH0379949B2
公开(公告)日：1991-12-20
申请号：JP4912382
申请日：1982-03-29
申请人： HITACHI LTD
发明人： KONO NAOFUMI
IPC分类号： H02M3/28 , H02J1/10

14. 发明专利

JPH0212781A TERMINAL STRUCTURE AND CONNECTING TERMINAL OF CIRCUIT BOARD 失效
公开(公告)号：JPH0212781A
公开(公告)日：1990-01-17
申请号：JP16372588
申请日：1988-06-30
申请人： HITACHI LTD
发明人： KONO NAOFUMI
IPC分类号： H05K1/14 , H05K3/34
摘要： PURPOSE:To prevent the occurrence of crack in the connecting part of a circuit board and a connecting terminal by disposing and fixing a plurality of connecting terminals onto the circuit board so that each terminal has a flexibility in the disposed direction. CONSTITUTION:A plurality of connecting terminals 2 are disposed so that each terminal has a flexibility in the disposed direction thereof and fixed to a circuit board 1. When the circuit board 1 having the thus disposed connecting terminals 2 is installed to a printed board such as glass epoxy resin, even if the difference of the coefficient of thermal expansion between the circuit board 1 and the printed board causes a relative expansion/contraction according to a temperature change, the stress is absorbed by contracting each connecting terminal 2 in the disposed direction thereof where the influence is most increased. Hence, no crack is caused in the plated part.

15. 发明专利

JPH10295075A POWER-SUPPLY CIRCUIT 失效
公开(公告)号：JPH10295075A
公开(公告)日：1998-11-04
申请号：JP10134497
申请日：1997-04-18
申请人： HITACHI LTD
发明人： KONO NAOFUMI , IMAI TSUTOMU
IPC分类号： G06F1/26 , H02H7/12 , H02M3/28
摘要： PROBLEM TO BE SOLVED: To constitute a power supply for a personal computer, which is low-cost and whose safety is high by a method, wherein two voltage values as reference values at which an overcurrent protective circuit at a switching power supply starts to operate are installed as operating points at the overcurrent protective circuit. SOLUTION: When a voltage generated at a resistor 4 exceeds a reference value expressed by Vref1=Vs ×R3/(R2+R3), a phase control circuit 20 controls the phase width of a control value so as to be narrow, and the output current of a control output terminal 8 is limited. At this time, when output power is small, resistors 26, 29 are selected in such a way that an overcurrent protective circuit functions, and an output is obtained as a small-capacity power supply. When the power supply is turned on in a state that a power-supply control circuit 32 is operable, a light-receiving part 14b is turned on at the same time as with the operation of a main load 33, and a resistor 25 is connected in parallel with the resistor 26. At this time, a reference voltage Vref2 becomes a value which is higher than the reference value Vref1. As a result, when a voltage across the both ends of the resistor 4 does not exceed the reference value Vref2, the overcurrent protective circuit does not function, and a power-supply circuit functions as a large-capacity power supply which is larger than that in conventional cases.

16. 发明专利

JPH05227754A POWER SUPPLY 失效
公开(公告)号：JPH05227754A
公开(公告)日：1993-09-03
申请号：JP2783092
申请日：1992-02-14
申请人： HITACHI LTD
发明人： OMORI TETSUO , MAEDA HIROKAZU , KONO NAOFUMI
IPC分类号： G05F1/10 , H02M7/21
摘要： PURPOSE:To realize substantial increase of power interruption sustaining time by detecting input voltage drop and performing back up with an auxiliary voltage taken out from main output side thereby varying the power interruption sustaining time depending on load power. CONSTITUTION:In the power supply, an AC power supply 1 is rectified through a rectifying circuit 2 and filtered through a capacitor 3 to produce a DC voltage. Upon interruption of AC input voltage under low load current, a rectified voltage and a voltage multiplied through a transformer drop uniformly with a reduction coefficient corresponding to the load current. The voltages drop slowly because of the low load current, but the capacitor voltage drops constantly because current consumption of an auxiliary power supply circuit is scarcely influenced by the magnitude of the load current. When energy is fed to the auxiliary voltage by connecting a diode, auxiliary voltage drop can be positioned at a value equal to the output voltage minus forward voltage drop of diode and a control circuit is prevented from entering into nonoperative state resulting in prolongment of power interruption sustaining time.

17. 发明专利

JPH05227746A CURRENT CONTROL CIRCUIT 失效
公开(公告)号：JPH05227746A
公开(公告)日：1993-09-03
申请号：JP3036892
申请日：1992-02-18
申请人： HITACHI LTD
发明人： KANOUDA TAMAHIKO , SATO MASAYOSHI , ONDA KENICHI , HAGIWARA SHUYA , MIZOGUCHI TETSURO , KONO NAOFUMI , FUJIKAWA KATSUMI , KINO JIRO
IPC分类号： H02M3/28
摘要： PURPOSE:To get a current circuit of low loss suitable for a high frequency switching power source by integrating a power MOSFET and a current detecting circuit on the same semiconductor substrate, and taking out one part of the unit cell of the power MOSFET to the other electrode. CONSTITUTION:For a current control circuit, when a power MOSFET 11 is tuned on, a current circulates from a rectifying smoothing circuit 2 to the primary side of a transformer 4 and a closed loop, and power is supplied to the secondary circuit, and shot diodes 5a and 5b rectify a high frequency AC, and a chock coil 6 and a capacitor 7 smooth it so as to control the voltage supplied to load 8 to be constant. Next, a feeble current equivalent to the cell ratio among a main current flows to a current detecting circuit 13 by connecting only the source electrodes of about 1-0.1% cells to the current detecting circuit 13, among the cells of the power MOSFET 11. This converts it into voltage and inputs it into a peak hold circuit 14, and only while a current flows to the MOSFET 11, it receives the output voltage, and during off, it holds the voltage level that it received at on.

18. 发明专利

JPH0318118A DRIVING CIRCUIT FOR MOSFET 失效
公开(公告)号：JPH0318118A
公开(公告)日：1991-01-25
申请号：JP15038589
申请日：1989-06-15
申请人： HITACHI LTD
发明人： NISHISU KOUJI , FUJIE TOSHIAKI , KONO NAOFUMI
IPC分类号： H03K17/66 , H03K17/687 , H03K17/691
摘要： PURPOSE:To eliminate the limit of an increase in speed based upon transistor(TR) characteristics by speeding up the discharging of an MOSFET gate capacitor to be driven by a simple circuit without using any TR. CONSTITUTION:A TR 2 is turned on and off with rectangular control pulses and the output of a DC power source 22 are converted by the alternate conduction of FETs 3 and 4 connected to PP form into rectangular driving pulse, which is supplied to the connection point between the FETs 3 and 4. The driving pulse is applied to the primary coil of a pulse transformer 11 through capacitors 9 and 10 in the ON state of the FET 4 when rising, but then falls to a voltage clamped by a Zener element 7. When an element 3 is ON, the polarity of the voltage impressed to the primary coil is inverted and a negative voltage clamped by the element 8 is obtained. A voltage applied between the gate and source of an FET rises when the driving control pulse rises and falls, so the gate-source capacity of the FET is charged and discharged speedily to shorten the switching time.

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