Panasonic Corporation

Matsushita Electric Industrial Co., Ltd.

Shingo Fukamizu

Yasunori Yamamoto

Shinichi Kuroshima

Hideaki Mori

Yutaka Nabeshima

Hiroki Matsunaga

Katsuhiro Onishi

Makoto Gotou

Susumu Yamamoto

Masaaki Ochi

Shuji Tamaoka

Takashi Katsuyama

A semiconductor integrated circuit relating to one aspect of the present invention includes a power transistor, at least one or more of first metal patterns functioning as a first electrode of the power transistor and at least one or more of second metal patterns functioning as a second electrode of the power transistor formed in an interlayer insulation film on the transistor, at least one or more of first busses electrically connected to a corresponding first metal pattern of the at least one or more of the first metal patterns, a single second bus electrically connected to the at least one or more of second metal patterns, and a contact pad provided to each of the at least one or more of first busses and the single second bus.

Semiconductor integrated circuit providing for wire bonding directly above an active circuit region, and manufacturing method thereof

Problems with accuracy reading position detection signal peaks and minute phase differences in the detection current make motor drive control easily susceptible to differences in motor characteristics. The rotor position is determined based on whether or not a terminal difference voltage, which is the difference voltage between the motor terminal voltage and the pseudo-neutral-point voltage when the motor phases are selectively energized, exceeds a specific threshold value. The phase energized to start the motor is determined based on this determination and the motor is energized accordingly to start. Instead of switching directly from the search step at the initial rotor position to the back-EMF voltage mode, a search and start mode that creates initial rotor speed sufficient to start the motor is executed before entering the back-EMF voltage mode.

Motor drive device and motor drive method

The semiconductor integrated circuit device includes: an active element, an interlayer insulting film, first and second metal patterns made of a first metal layer formed right above the active element, first and second buses made of a second metal layer formed right above the first metal layer, and contact pads provided on the first and second buses. The contact pad has a probe testing region and a bonding region.

Semiconductor integrated circuit device and fabrication method for the same

A motor driving apparatus includes a virtual difference voltage detecting unit operable to detect a difference voltage between a virtual neutral point of a resistor circuit connected in parallel to motor coils and a terminal of a motor coil in non-conduction state, a rotor position detecting unit operable to detect a position of the rotor based on the difference voltage, and a controller operable to control commutation of an inverter based on the rotor position. The motor driving apparatus has a searching start mode for detecting the rotor position and energizes the coils, and a back electromotive voltage feedback mode for controlling commutation based on the back electromotive voltage. In the searching start mode, a rotor position searching process and a rotation start torque applying process are alternately performed.

Motor driving apparatus, motor driving method and disk driving apparatus

A semiconductor integrated circuit includes a power transistor formed on a semiconductor substrate, a plurality of first metal patterns and a plurality of second metal patterns which are formed right above the power transistor and function as a first electrode and as a second electrode of the power transistor, respectively, a plurality of first buses each electrically connected with, of a plurality of first metal patterns, a corresponding first metal pattern, a plurality of second buses each electrically connected with, of a plurality of second metal patterns, a corresponding second metal pattern, wherein one contact pad is provided to each of a plurality of first buses and a plurality of second buses.

Semiconductor integrated circuit and method for manufacturing the same

A motor driving apparatus includes a neutral point difference voltage detecting unit operable to detect a difference voltage between a virtual neutral point of a resistor circuit connected in parallel to motor coils and an actual neutral point which is a common connection point of the motor coils, a rotor position detecting unit operable to detect a position of the rotor based on the difference voltage, and a controller operable to control commutation of an inverter. A rotation start torque applying process applies a rotation start pulse for providing rotation torque to the rotor based on a determined rotor position.

Problems with accuracy reading position detection signal peaks and minute phase differences in the detection current make motor drive control easily susceptible to differences in motor characteristics. The rotor position is determined based on whether or not a neutral point difference voltage, which is the difference voltage between the neutral point voltage and the pseudo-neutral-point voltage when the motor phases are selectively energized, exceeds a specific threshold value. The phase energized to start the motor is determined based on this determination and the motor is energized accordingly to start. Instead of switching directly from the search step at the initial rotor position to the back-EMF voltage mode, a search and start mode that creates initial rotor speed sufficient to start the motor is executed before entering the back-EMF voltage mode.

Motor drive device

Optical disc drives designed for reduced power consumption switch the supply voltage in three stages between first, second, and third power supplies. The reduction in power consumption that is possible in the focusing and tracking drive circuits with three stage switching control is limited. This drive apparatus enables further reductions in power consumption. A drive output tracking signal is generated according to the drive conditions of the focusing or tracking drive circuit. The drive output tracking signal is applied to the drive circuit power supply, and the power supply is controlled according to the drive output tracking signal. A power supply change detector detects sudden changes in the drive output tracking signal, and inputs the detection signal to the DSP controlling the entire system. The DSP determines whether to improve the power supply response by comparison with predetermined conditions, and returns the result to the power supply.

Drive apparatus

A reference signal generation unitgenerates a reference signal VCA representing a limit indicator. Under the control of a PWM control unit, a bridge rectification circuitcontrols the current supplied to a coilto the limit indicator, using a current chopper method. Therewith, the circuitimplements synchronous rectification where transistorsandare brought into conduction when the current supply is stopped, forming a closed circuit with the coil, and a regenerative current circulates in the closed circuit. During a time period when the reference signal is decreasing relatively rapidly, a SR prohibition unitprohibits the transistororfrom being brought into conduction when the current supply is stopped, and thereby the decay of regenerative current is accelerated.

Stepping motor drive device and method

The reference signal generation unitintegrates, in the integration circuit, a staircase signal generated by the staircase generation unit, and thereby generates a reference signal VCTA whose signal level changes continuously over time, and which represents a limit value for the supply current. According to the control of the PWM control unit, the bridge rectification circuitmaintains the coil supply current at the limit value, using a current chopper method. Additionally, when the current supply is stopped, the bridge rectification circuitperforms synchronous rectification, where the transistorsandare brought into conduction, and a regenerative current is circulated in a closed circuit formed with the coil. When the reference signal VCTA decreases relatively fast, the synchronous rectification prohibition unitprohibits one of the transistorsandfrom being brought into conduction when the current supply is stopped.

A reference signal generation unit generates a reference signal VCA showing a current limit value with a staircase waveform. A PWM control unit compares a measurement signal SENA obtained by a coil current measurement unit with the reference signal VCA at intervals of a PWM timing signal generated by a PWM timing signal generation unit, and switches transistors of a bridge rectification circuit ON and OFF according to the comparison, thereby PWM controlling a supply current to a coil. A discharge instruction signal generation unit issues a discharge instruction signal MMCPA when the reference signal VCA decreases. In response, a PWM control unit forms a current path in the bridge rectification circuit to cause a regenerative current to flow back into a power supply and capacitor.

A reference signal generation unit integrates a staircase signal, to produce reference signal VCTA whose waveform has no abrupt changes in level and which shows a current limit value. A PWM reference signal generation unit generates a PWM reference signal. A supply current measurement unit measures a supply current to a coil. A PWM control unit compares reference signal VCTA with the measurement value of the supply current measurement unit in each period of the PWM reference signal, and sets each transistor in a bridge rectification circuit in a conducting state or a nonconducting state according to the comparison result. In this way, the supply current to the coil is controlled to approach the current limit value shown by reference signal VCTA.

In a disk drive apparatus of the present invention, power transistors of a power supplying part execute high-frequency switching operation and form current paths to three-phase windings so as to rotate a disk, a position detecting part produces a position signal which responds with terminal voltages of the three-phase windings, an activation operation part controls active periods of the power transistors in response to an output signal of the position detecting part, a commanding part produces a command signal in response to an output pulse signal of the position detecting part, and a switching operation block produces a switching pulse signal in response to a comparison result of a current detection signal with the command signal. The activation operation part produces a slew-rate switching signal which responds with the switching pulse signal, and causes at least a power transistor of the power supplying part to follow the slew-rate switching signal, thereby executing high-frequency switching of the power transistor in response to the slew-rate switching signal.

Growing community of inventors

Osaka, Japan

Shingo Fukamizu