Renesas Electronics Corporation

Takeshi Ohtsuki

Minoru Kurosawa

Satoshi Narumi

Akihiro Nakatani

Mitsumasa Murakami

Akihisa Nomura

Aritsune Nagamura

Shunya Yamane

Mamoru Morotomi

Hiromi Takeda

The semiconductor device includes: a current detection circuit configured to detect a current flowing through a three-phase motor by driving of a drive circuit; and a controller configured to control the drive circuit, based on the detected current. The controller is configured to control, when the three-phase motor is stationary, an energization pattern in such a way that a wave detection current sequentially flows from the drive circuit to each phase of the three-phase motor, to obtain, from the wave detection current detected by the current detection circuit, a first, a second and a third interphase current differences, each of which is a difference among wave detection currents flowing in directions opposite to one another, to determine the energization pattern based on a magnitude relationship among the first, the second and the third interphase current differences.

Semiconductor device, motor drive system, and control method thereof

The magnetic pole position of the rotor is estimated with high accuracy at the initial start of a three-phase motor of the sensorless system. Semiconductor device for driving and controlling the three-phase motor of the sensorless system have a detector connected to the three-phase output nodes of the inverter circuit and the virtual neutral point (or neutral point), and detecting a voltage generated in the output node of the non-energized phase of the three-phase. Controller applies the initial drive voltage by the inverter circuit to any two phases of the three-phase motor based on the estimated position of the magnetic pole of the rotor in the stop state. Controller estimates the position of the rotor based on a difference voltage detected by the detector in a driving voltage applying period and a regeneration period immediately after or immediately before the driving voltage applying period.

Semiconductor device, motor drive system, and method of starting motor

An operation part calculates a shake amount of an imaging apparatus in accordance with a first operation system or a second operation system on the basis of an output signal of a sensor detecting an acceleration or angular velocity to determine a camera-shake correction amount correcting the shake amount. The operation part calculates the output signal of the sensor or a value obtained by integrating an integrated signal of the output signal of the sensor as a shake amount. The operation part includes an imperfect integrator. An operation system setting part sets an operation system of the operation part on the basis of the shake amount calculated by the operation part. In the second operation system, the operation system setting part increases a cut-off frequency of the imperfect integrator more than in the first operation system.

Camera controller

An exemplary embodiment of the present invention is an autofocus method that includes moving a focus lens according to an image signal generated from an image of a subject formed by an imaging optical system with a focus lens, obtaining a focus contrast of each of multiple image signals generated in a case of moving a position of the focus lens; and determining a moving direction of the focus lens according to the multiple obtained focus contrasts in response to a focus instruction.

Apparatus, method, and program product for autofocus including a contrast obtaining unit that obtains a focus contrast and a control unit that controls a focus lens according to the focus contrast

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Tokyo, Japan

Takeshi Ohtsuki