Panasonic Corporation

Matsushita Electric Industrial Co., Ltd.

Panasonic Intellectual Property Management Co., Ltd.

Kazuhiro Murata

Naohiko Morota

Yoshihiro Mori

Keita Kawabe

Akihiro Yamamoto

Ryoji Inutsuka

Sakae Kobayashi

Shinzou Eguchi

Koichi Yabuki

Kouichi Yoshida

Koji Suzuki

Takashi Saji

Tetsuji Yamashita

Yoshiyuki Nagai

Kunio Ohe

Tetsuyuki Fukushima

Hideo Sakon

Tatsuya Sakurai

Hiroko Sakimura

A switching power supply apparatus of the present disclosure is a device connection state detection circuit that detects a connection state in a load device connection terminal in a power supply system having the load device connection terminal. The device connection state detection circuit includes a transformer, a switching element, a pulse generator, and a waveform detection circuit. The waveform detection circuit detects a voltage or a current generated in a primary winding wire or a secondary winding wire of the transformer in accordance with operation of a pulse signal, compares the detected voltage or current with a preset reference value, and outputs an output signal in accordance with a comparison result, to an OFF terminal.

Switching power supply apparatus

A switching power supply apparatus includes: an input terminal; an output terminal; a switching element; an input and output converting unit which converts input voltage applied through the switching element into output voltage to supply output power to a load; an output voltage feedback unit which outputs a feedback signal, based on the output voltage; a switch current detecting unit which detects current flowing through the switching element; an oscillating frequency setting unit which sets the switching frequency of the switching element, based on the feedback signal; a peak current setting unit which controls turn-off of the switching element by setting a current threshold such that a switch current peak (i) is constant regardless of a change in the output power and (ii) increases as the input voltage increases; and a switching control unit which controls switching operation of the switching element.

Switching power supply apparatus and semiconductor device

The switching power supply device includes: an input unit which receives an input voltage; a transformer which includes a primary winding and a secondary winding; an output unit which provides an output voltage; a switching element; and a control circuit. The control circuit includes: a Ton measuring unit which measures a secondary-side conduction time period; a frequency control circuit which provides a second signal used for changing an on-frequency of the switching element in order to narrow a difference between the measured secondary-side conduction time period and a reference value; a primary current detecting circuit which detects a primary current; a current comparing circuit which provides a third signal used for turning the switching element off when the detected primary current becomes equal to a threshold value; and an oscillation control circuit which controls on-off switching of the switching element according to the second signal and the third signal.

Switching power supply device having a constant voltage characteristic and semiconductor device

A switching power supply device including: a power transformer including a primary winding, a secondary winding, and an auxiliary winding; a switching element which is connected to the primary winding; an output voltage generation circuit which converts, into a direct-current voltage, a voltage induced in the secondary winding; a secondary-side on-time signal generation circuit which generates a secondary-side on-time signal indicating a secondary-side on-time; and a switching control circuit which controls a switching operation of the switching element so that the second direct-current voltage falls within a specified range, wherein the switching control circuit controls the switching operation so that the direct-current voltage becomes equal to or below an overvoltage specified value when the secondary-side on-time becomes smaller than a set value.

Switching power supply device with a switching control circuit

The switching power supply apparatus includes a transformer including a primary winding, a secondary winding, an auxiliary winding, a switching device connected to the primary winding, an output voltage generation circuit which is connected to the secondary winding and generates an output voltage, and an auxiliary power voltage generation circuit which is connected to the auxiliary winding and generates an auxiliary power voltage. The switching power supply apparatus also includes a control circuit, which operates using the auxiliary power voltage and controls a driver circuit so that an intermittent oscillation is performed when the output voltage is higher than a first output voltage, and which controls a peak of a current flowing through a switching device is lower than a peak in a normal mode, when the auxiliary power voltage is lower than a first auxiliary power voltage in the intermittent oscillation.

At the starting time and an overload time in which the output voltage of the switching power source apparatus is low, if an overcurrent state, in which the ON period of the switching device becomes short and a current not less than the current limit value of the switching device flows through the switching device, occurs, this overcurrent state is detected. The blanking period of a blanking pulse signal is made shorter than the blanking period that is obtained during steady operation, and the ON period of the switching device is made shorter. Hence, the device current flowing through the switching device can be made small in each pulse for the switching operation, and, at the same time, the device current is suppressed from increasing each time a pulse for the switching operation is generated.

Switching control circuit, semiconductor device and switching power source apparatus

A switching power supply circuit, which includes: a switch; a coil serving as an energy transmitting element; and a capacitor serving as an output generation circuit that outputs, as an output voltage, the energy transmitted from the coil. The switching power supply circuit also includes an output voltage detection circuit that generates a detection signal according to the output voltage; a PNP transistor serving as a transmission circuit that outputs a transmission signal according to a value of the detection signal; and a controller that controls the switch according to the transmission signal. The switching power supply circuit further includes a diode serving as a rectifying element connected between the transmission circuit (PNP transistor) and the controller.

Switching power supply circuit

The present invention provides a switching power supply device including a switching element, a control circuit controlling the switching element, a transformer having an auxiliary winding, a potential clamp circuit connected to one of outputs of the transformer, a delay capacitor connected to an output of the potential clamp circuit, a potential detection circuit detecting a potential at the delay capacitor, and an overload protection actuation circuit realizing overload protection. During an overload, the delay capacitor is charged only by ringing of the auxiliary winding, generated immediately after the switching element is turned off, through the potential clamp circuit. Then, the potential detection circuit supplies an actuation signal to a latch stop circuit by detecting that the potential at the delay capacitor rises. The latch stop circuit latches and stops the switching operation of the switching element to realize the overload protection when the actuation signal is fed into the latch stop circuit. Thus, the overload protection can be realized with a sufficient delay time by the relatively small delay capacitor.

Switching power supply device

A plurality of arrangements for detecting an overload of energy supplied to an output part enables selecting latch-off or auto-recovery overload protection by the operation of a switching device. When the drain current peak of the switching device exceeds a predetermined level denoting an overload, the FB pin voltage also rises to latch off, and when the drain current peak then reaches a maximum level, the CC pin voltage drops to a predetermined level and limits the oscillation period of the switching device because output power cannot be increased even if the load increases further. Latch-off overload protection can be applied when the drain current peak exceeding a predetermined level is detected, and auto-recovery overload protection can be applied when the CC pin voltage is detected to drop to a predetermined level.

Switching power supply device, semiconductor device, and control method

A feedback circuit () generates an error amplification signal VEAO for stabilizing an output voltage Vo at the reference voltage. The reference voltage is set beforehand in the feedback circuit (). The peak value of drain current ID passing through a switching element () is controlled by the error amplification signal VEAO and the output voltage Vo is stabilized. Meanwhile, when a load () increases, a reference voltage variable circuit () increases the internal reference voltage of the feedback circuit () based on the error amplification signal VEAO, so that fluctuations in output voltage due to load fluctuations are reduced.

Switching power supply

A power supply regulation circuit is provided which can achieve a preferable constant current drooping characteristic without the need for a constant current control circuit on the secondary side. During a constant current operation, a switching element () is turned on so as to keep constant the on duty of secondary current passing through a secondary winding (B) of a transformer (), so that a constant current drooping characteristic is achieved. Further, at this moment, a current limit dictating the maximum value of drain current (ID) passing through the switching element () is changed between first and second levels during the on time of the switching element such that the drain current (ID) has a constant peak value.

Power supply regulator circuit and semiconductor device

An apparatus and method determine a size of a bonding film for bonding a bonding target having a size which varies due to temperature variation, at an environmental temperature which is different from a temperature during use. The method includes measuring an actual size of the bonding portion of the circuit electrode at the first temperature, comparing the actual size of the bonding portion with a designed size of the bonding portion at the first temperature, and determining a cutting size of the bonding material based on a comparison result and mounting the bonding material over the bonding portion.

Method and apparatus for determining processing size of bonding material

An electronic parts mounting apparatus for divisionally recognizing an electronic part ( ) even when the apparatus is arranged in such that the relative positional relation between a recognition camera ( ) and a nozzle ( ) cannot be varied. The electronic part ( ) is vacuum-clamped by a nozzle ( ), the posture of the nozzle ( ) or the posture of the electronic part ( ) is changed a plurality of times by a rotary driving member ( ), and a part of the electronic part ( ) imaged by the recognition camera ( ) every time the posture of the electronic part ( ) is changed, whereby the part is recognized. Thus, the recognition of the contour of the electronic part ( ) becomes possible, and the electronic part can be mounted accurately on a circuit board by making a positional correction on the basis of the amount of deviation obtained.

Electronic parts mounting apparatus

The invention provides an electronic parts mounting machine and an electronic parts packaging method wherein even when a system does not include driving means, such as an XY robot, for driving a mounting head, there is no possibility of causing a decrease in measurement accuracy or a need to allocate a larger space for the installation and movement of a test unit of a lead misalignment tester. When a lead misalignment test is conducted on each lead of an electronic part, a suction nozzle is rotated and, at the same time, the test unit is moved such that the test point of the test unit scans each lead of the electronic part sucked by the suction nozzle while said test point crosses said lead.

Growing community of inventors

Osaka, Japan

Kazuhiro Murata