Abstract: The motor drive circuit 100 supplies a drive current to the motor 2 to drive the motor. Each of the first Hall amplifier HAMP1 to the third Hall amplifier HAMP3 is provided for each phase of the motor 2 and receives a pair of Hall signals from a corresponding phase Hall element to generate each phase sine wave voltage SIN_U, SIN_V and SIN_W by amplifying a difference between the pair of Hall signals. Each of the first PWM comparator PCMP1 to the third PWM comparator PCMP3 is provided for each phase of the motor 2 and compares the corresponding phase sine wave voltage SIN_U, SIN_V and SIN_W, with the periodic voltage Vosc to generate each phase PWM signal PWM_U, PWM_V and PWM_W. The drive unit 10 subjects a phase coil, a target to be driven, to pulse drive by using the pulse modulated signal from the corresponding PWM comparator.

Abstract: An energization signal generating circuit respectively compares back electromotive forces generated in coils of each phase of a motor with a midpoint voltage of each phase, and generates energization signals. A pulse signal generating circuit generates a pulse signal in which duty ratio is controlled according to torque. A ramp signal generating circuit divides, into a plurality of times, a period of a frequency generation signal obtained by synthesizing the energization signals, and, for each divided time unit, generates a ramp signal in which pulse width gradually changes, and which has a frequency the same as the pulse signal. An output circuit supplies a drive current to the coils of each phase, based on the energization signals, the pulse signal, and the ramp signal.

Abstract: A back electromotive detection comparator compares back electromotive voltages Vu to Vw with a common voltage Vn of coils, and generates first rectangular wave signals Pu to Pw. A masking circuit performs masking of the first rectangular wave signals Pu to Pw, and outputs the resultant signals as second rectangular wave signals Mu to Mw. An output circuit supplies a drive current to coils on the basis of the second rectangular wave signals Mu to Mw. A frequency generating circuit generates a frequency generation signal SigFG whose level switches at every edge of the second rectangular wave signals Mu to Mw. A mask signal generating circuit generates a mask signal MSK which is at a high level during an interval multiplied by a coefficient to a pulse width Tp of the frequency generation signal SigFG after level transition of the frequency generation signal SigFG.

Abstract: The motor drive circuit 100 supplies a drive current to the motor 2 to drive the motor. Each of the first Hall amplifier HAMP1 to the third Hall amplifier HAMP3 is provided for each phase of the motor 2 and receives a pair of Hall signals from a corresponding phase Hall element to generate each phase sine wave voltage SIN_U, SIN_V and SIN_W by amplifying a difference between the pair of Hall signals. Each of the first PWM comparator PCMP1 to the third PWM comparator PCMP3 is provided for each phase of the motor 2 and compares the corresponding phase sine wave voltage SIN_U, SIN_V and SIN_W with the periodic voltage Vosc to generate each phase PWM signal PWM_U, PWM_V and PWM_W. The drive unit 10 subjects a phase coil, a target to be driven, to pulse drive by using the pulse modulated signal from the corresponding PWM comparator.

Abstract: A back electromotive detection comparator compares back electromotive voltages Vu to Vw with a common voltage Vn of coils, and generates first rectangular wave signals Pu to Pw. A masking circuit performs masking of the first rectangular wave signals Pu to Pw, and outputs the resultant signals as second rectangular wave signals Mu to Mw. An output circuit supplies a drive current to coils on the basis of the second rectangular wave signals Mu to Mw. A frequency generating circuit generates a frequency generation signal SigFG whose level switches at every edge of the second rectangular wave signals Mu to Mw. A mask signal generating circuit generates a mask signal MSK which is at a high level during an interval multiplied by a coefficient to a pulse width Tp of the frequency generation signal SigFG after level transition of the frequency generation signal SigFG.

Abstract: An energization signal generating circuit respectively compares back electromotive forces generated in coils of each phase of a motor with a midpoint voltage of each phase, and generates energization signals. A pulse signal generating circuit generates a pulse signal in which duty ratio is controlled according to torque. A ramp signal generating circuit divides, into a plurality of times, a period of a frequency generation signal obtained by synthesizing the energization signals, and, for each divided time unit, generates a ramp signal in which pulse width gradually changes, and which has a frequency the same as the pulse signal. An output circuit supplies a drive current to the coils of each phase, based on the energization signals, the pulse signal, and the ramp signal.

Abstract: A method of producing a polarizing plate, including the step of laminating a pair of curled protective sheets onto opposite surfaces of a polarizer respectively so that respective curling directions of the pair of curled protective sheets are reverse to each other, wherein the laminating index of the pair of protective sheets is selected to be not higher than 60 in order to restrain the polarizing plate from being curled.

Abstract: In a load-driving semiconductor device, a part of metal interconnection in a metal interconnection layer is used to form a detecting resistor for detecting an output current, and a resistance-measuring pad for measuring a resistance value of the detecting resistor is provided. The load-driving semiconductor device generates a trimmed reference voltage in accordance with the resistance value of the detecting resistor, and controls drive of a load based on a comparison between the reference voltage and a detected voltage according to a voltage drop of the detecting resistor. Therefore, it is possible to provide a load-driving semiconductor device in which a current-detecting resistor for detecting a current that flows through a load is embedded to reduce space required on a substrate and thus reduce cost, and a current can be detected with high accuracy.

Abstract: A method of producing a polarizing plate, including the step of laminating a pair of curled protective sheets onto opposite surf aces of a polarizer respectively so that respective curling directions of the pair of curled protective sheets are reverse to each other, wherein the laminating index of the pair of protective sheets is selected to be not higher than 60 in order to restrain the polarizing plate from being curled.

Abstract: The present invention provides a process for the production of a semiconductor device comprising a semiconductor element provided on a printed circuit board with a plurality of connecting electrode portions provided interposed therebetween, the gap between said printed circuit board and said semiconductor element being sealed with an underfill resin layer.

Abstract: Described is a process for the fabrication of a semiconductor device, which comprises a step of simultaneously or successively mounting at least one semiconductor element having a connecting electrode portion onto each of both sides of an interconnection circuit substrate through an encapsulating resin layer and a step of connecting said at least one semiconductor element with an interconnection electrode on each of both sides of said interconnection circuit substrate by making use of the adhesive force of said encapsulating resin layer.

Abstract: A method of production of a semiconductor device such as a plastic pin grid array (PPGA) and a plastic ball grid array (PBGA) having a cavity-fill form. In this method, first, a semiconductor element (3) is placed in a cavity (6) formed in a multiple step-like substrate (2). Under this state, a pellet (7), which is in a solid state at a normal temperature, made of an encapsulating resin composition containing specific components, and has specific characteristics, is placed on the semiconductor element (3). Next, the semiconductor device is heated so that the pellet can melt to fill the cavity (6) with the composition, thereby encapsulating the semiconductor device (3). According to the present invention, a semiconductor device having low stress performance and excellent moisture-proof reliability can be efficiently produced.

Abstract: A semiconductor device comprising a semiconductor element encapsulated with a cured resin having at least two secondary differential peaks of linear thermal expansion by a thermomechanical analytical measurement, the interval between the peaks being at least 20.degree. C. The semiconductor device encapsulated with the cured resin does not cause a warp and is excellent in the TCT test characteristics and the cracking resistance.