公开(公告)号：JP2000112543A

公开(公告)日：2000-04-21

申请号：JP27822898

申请日：1998-09-30

Applicant: DENSO CORP

Inventor： UEDA NOBUTADA

IPC: G05F1/56 ,  H03F3/343

Abstract: PROBLEM TO BE SOLVED: To stably supply load currents in response to the temperature difference of a force Tr and a sense Tr. SOLUTION: A current mirror circuit is constituted of a force Tr1 and a sense Tr2, and they are controlled so that each source voltage can be made equal by a feedback amplifier circuit 5 and a control circuit 6. Constant currents are supplied to the sensor Tr2 by a constant current circuit 4, and the constant current circuit 4 is provided with a reference transistor 41 and plural output transistors 42 constituting the current mirror circuit. In this case, the temperature characteristics of the constant currents outputted from the constant current circuit 4 are made opposite to the temperature characteristics of currents running through the force Tr1 so that even when the temperature difference of the force Tr1 and the sensor Tr2 is generated, currents running through the force Tr1 can be made constant.

公开(公告)号：JP2001267898A

公开(公告)日：2001-09-28

申请号：JP2000074144

申请日：2000-03-16

Applicant: DENSO CORP

Inventor： UEDA NOBUTADA

IPC: H02M1/00 ,  H03K17/08 ,  H03K17/695

Abstract: PROBLEM TO BE SOLVED: To provide an inductive load driving circuit which can suppress erroneous detection by a fly back voltage when detecting the overcurrent of a current supplied to an inductive load and in which the damage of a switching means due to overcurrent is difficult to occur. SOLUTION: An inductive load driving circuit 1, when controlling the drive of an inductive load L, compares the respective source potential (first potential V1 and second potential V2) of a first transistor 11 and a second transistor 13, judges the value of a current flowing in the first transistor 11 based on a current flowing in the second transistor 13 and detects overcurrent when the control command signal Sa from a control logic 17 is in a high level. When the control command signal Sa is in a low level, an overcurrent detection stop circuit 31 stops power supply to a second conduction route including the second transistor 13 and the detection of overcurrent is stopped. Thus, the erroneous detection of overcurrent by the fly back voltage can be suppressed.

公开(公告)号：JPH1022800A

公开(公告)日：1998-01-23

申请号：JP17016396

申请日：1996-06-28

Applicant: DENSO CORP

Inventor： UEDA NOBUTADA

IPC: H03K17/08 ,  G05F3/24

Abstract: PROBLEM TO BE SOLVED: To prevent current detection accuracy from being deteriorated against a temperature change in the case that a current is detected by a current mirror circuit. SOLUTION: A power MOS transistor(TR) 3 and a current detection MOS TR 4 are connected in parallel to form a current mirror circuit and 1st and 2nd compensation resistors 5a, 5b are provided to a source and a drain of the current detection MOS TR 4 so that a resistance ratio of a wiring resistor to an ON resistance of the current detection MOS TR 4 is nearly equal to a resistance ratio of a wiring resistor to an ON resistance of the power MOS TR 3.

公开(公告)号：JP2002344297A

公开(公告)日：2002-11-29

申请号：JP2001147714

申请日：2001-05-17

Applicant: DENSO CORP

Inventor： TSUCHIDA MASAHIRO ,  KOYAMA YOSHINORI ,  UEDA NOBUTADA ,  FUJIMOTO YUTAKA

IPC: H03K17/14 ,  H03K17/567

Abstract: PROBLEM TO BE SOLVED: To match conduction time of an electrical load being command to an actual conduction time, regardless of the magnitude of impedance of the electrical load. SOLUTION: A current control circuit 20 controls the gate potential of a transistor Q11, such that a load current IL and a trapezoidal wave signal Sb coincide with each other. When a drive command signal Sa goes to H, the trapezoidal wave signal Sb increases with a constant inclination, and when the transistor Q11 operates in a linear region due to increase of the load current IL, the gate voltage VGS increases abruptly. A saturation state detecting circuit 21 brings a current saturation signal Sc to L, at a moment when the gate voltage VGS exceeds a reference voltage Vr, and in response thereto, a trapezoidal wave generating circuit 19 stops increase of the trapezoidal wave signal Sb and holds the trapezoidal wave signal Sb. When the drive command signal Sa goes to L, the trapezoidal wave signal Sb decreases with a fixed slope, and the load current IL follows up the trapezoidal wave signal Sb and decreases.

公开(公告)号：JPH09290704A

公开(公告)日：1997-11-11

申请号：JP10296896

申请日：1996-04-24

Applicant: DENSO CORP

Inventor： MAYUMI NOBUO ,  UEDA NOBUTADA

IPC: B60R21/16 ,  B60R16/02 ,  B60R16/03 ,  B60R21/01 ,  G01P15/08 ,  H02J9/06 ,  H02M3/07 ,  B60R21/32

Abstract: PROBLEM TO BE SOLVED: To efficiently use a single backup capacitor as an ignition mechanism and an ignition determining mechanism in common and reduce capacity of a boosting circuit so as to miniaturize the boosting circuit by improving a connecting structure between the backup capacitor, the ignition mechanism, and the ignition determination mechanism. SOLUTION: By means of a switch circuit 50, a boosting circuit 30 and a backup capacitor 40 are cut off from an ignition determination mechanism 20 when voltage is normally impressed to the ignition determination mechanism 20 via a diode D2 from a battery Ba, and if impression of voltage from the battery Ba to the ignition determination mechanism 20 is cut off, voltage is impressed from the backup capacitor 40 to the ignition determination mechanism 20 before an impressed voltage to the ignition determination mechanism 20 lowers its operating voltage range.

公开(公告)号：JP2003198350A

公开(公告)日：2003-07-11

申请号：JP2001390431

申请日：2001-12-21

Applicant: DENSO CORP

Inventor： FUKUDA YUTAKA ,  NAKANO TAKASHI ,  UEDA NOBUTADA ,  MIURA SHOJI

IPC: H03K17/08 ,  H03K17/687 ,  H03K19/0175

Abstract: PROBLEM TO BE SOLVED: To provide a load driving circuit which can secure conformity in current waveforms of a MOS transistor when it is switched on/off and the same in a steady state. SOLUTION: A power source +B, a load 1, and a force transistor Qf are connected in series, a sense transistor Qs and a detection resistor Rs are connected in parallel with the force transistor Qf. The force transistor Qf and the sense transistor Qs are turned on and off by a gate drive circuit 2. When a voltage generated across the detection resistor Rs excesses a predetermined value, a transistor 3 limits the current supplied to the load 1. when the transistor Qf, Qs are switched from off to on, or vice-versa, a substrate potential adjustment circuit 4 adjusts the substrate potential of the sense transistor Qs, so that waveform shaping for the current supplied to the sense transistor Qs is performed. COPYRIGHT: (C)2003,JPO

公开(公告)号：JP2001308195A

公开(公告)日：2001-11-02

申请号：JP2000118319

申请日：2000-04-19

Applicant: DENSO CORP

Inventor： KOYAMA YOSHINORI ,  UEDA NOBUTADA ,  FUJIMOTO YUTAKA

IPC: H01L21/822 ,  H01L21/8234 ,  H01L27/04 ,  H01L27/088 ,  H01L29/06 ,  H01L29/417 ,  H01L29/78

Abstract: PROBLEM TO BE SOLVED: To provide a semiconductor device in which current control of a load drive circuit can be carried out with high accuracy. SOLUTION: A substantially square shape is constituted of the drain cells 10 and source cells 11 of a main LDMOS and a sense LDMOS and the drain cells 11 of the sense LDMOS are arranged to pass through both the central part and the corner parts of the substantially square shape. More specifically, they are arranged such that the drain lead wires 13 for the sense LDMOS form one diagonal of the substantially square shape. Consequently, variation in the ON resistance of LDMOS arranged at the corners of the substantially square shape and variation in the ON resistance of LDMOS arranged in the central part of the substantially square shape are averaged and can be taken out as a detection value. Since variations in the ON resistance can be prevented and the current mirror ratio can be prevented from being shifted, current control of a load drive circuit can be carried out with high accuracy.

公开(公告)号：JPH10181519A

公开(公告)日：1998-07-07

申请号：JP3048597

申请日：1997-02-14

Applicant: DENSO CORP

Inventor： UEDA NOBUTADA ,  MAYUMI NOBUO ,  SAITO MITSUHIRO ,  OKUDA KATSUICHI

IPC: B60R21/16 ,  B60R21/01 ,  G05F3/26 ,  B60R21/32

Abstract: PROBLEM TO BE SOLVED: To supply a constant current to a squib without providing a current detecting resistance in a current supply course toward the squib to develop an air bag. SOLUTION: Forth Tr15 is provided in series to a squib, and Sense Tr19 to compose a current mirror circuit with the Forth Tr15 is connected in parallel. Constant current is supplied from a constant current source 20 to the Sense Tr19. A computation amplification circuit 21 controls the gate voltages of the Forth Te15 and of the Sense Tr19 so that the source voltage of the Forth Tr15 an that of the Sense Tr19 may be equal. Thus, in the case where an igniting power transistor 13 has been turned on, the constant current corresponding to the current mirror ratio of the current mirror circuit is supplied from the Forth Tr15 to the squib 11.

公开(公告)号：JP2002168898A

公开(公告)日：2002-06-14

申请号：JP2000369926

申请日：2000-12-05

Applicant: DENSO CORP

Inventor： TSUCHIDA MASAHIRO ,  UEDA NOBUTADA

IPC: G01R31/316 ,  G01R31/00

Abstract: PROBLEM TO BE SOLVED: To provide an inspection method for temperature characteristics of semiconductor device for power source capable of easily and properly conducting product inspection. SOLUTION: The power source IC1 is constituted of a high accuracy power source circuit 2, a memory element 3 and other function circuit 4. For inspecting the temperature characteristics of the power source IC1, the output voltage from the power source IC1 at the maximum temperature (110 deg.C) of the measuring temperature range (-40 deg.C to 110 deg.C) is stored in a memory means. When the output voltage of the power source IC1 at a reference room temperature (25 deg.C) is measured, fluctuation range of output voltage in the measurement temperature range is predicted based on the voltage difference between the output voltage and the output voltage stored in the memory element 3 and between the maximum temperature and the reference room temperature. If the fluctuation range and the output voltage of the reference room temperature fulfill a temperature specification, the power source IC1 judges to be a good product.

公开(公告)号：JP2001267899A

公开(公告)日：2001-09-28

申请号：JP2000074145

申请日：2000-03-16

Applicant: DENSO CORP

Inventor： UEDA NOBUTADA

IPC: G05F1/10 ,  H03K17/08 ,  H03K17/14 ,  H03K17/687

Abstract: PROBLEM TO BE SOLVED: To provide a load driving circuit which can suppress the influence of temperature gradient in IC incorporating a power element for detecting a current. SOLUTION: In the load driving circuit 1, power is supplied from a power line LV to a load LL by controlling the drive of a first transistor 11 and voltages at both ends of a detection resistor 25 are compare with the potential of the positive polarity of a constant voltage power source 29 for detecting overcurrent in the first transistor 11. A correction circuit 47 corrects the potential of the positive polarity of the constant voltage power source 29 to be higher in accordance with a temperature difference between the first transistor 11 and a second transistor 13, which is detected by a temperature difference detection circuit 41. Even if the proportional relation of currents flowing in the first transistor 11 and the second transistor 13, changes due to the temperature difference generated by power consumption, overcurrent in the first transistor 11 can precisely be detected.