摘要:
PROBLEM TO BE SOLVED: To suppress current consumption without being easily influenced by element dispersion in manufacturing and without increasing a circuit area.SOLUTION: A power supply circuit 1 includes: a bridge circuit which generates an output voltage to be supplied to a load circuit having an amplifier including a CMOS inverter and generates a current allowed to flow into a first current path and a current allowed to flow into a second current path in accordance with a voltage difference between the output voltage and a predetermined set voltage to be supplied to the load circuit; and a current-current conversion part which generates a current allowed to flow into a third current path to the load circuit in accordance with a different error current between the current allowed to flow into the first current path and the current allowed to flow into the second current path by using an input power supply voltage. The set voltage is voltage to be supplied to the load circuit so as to obtain minimum transconductance of an amplifier capable of performing normal operation.
摘要:
PROBLEM TO BE SOLVED: To compensate for bias changes due to aging and to variations in IC process, power supply voltage, temperature, and/or other phenomena.SOLUTION: An apparatus may include an amplifier and a bias circuit. The amplifier may include at least one transistor coupled to an inductor. The bias circuit may generate at least one bias voltage for the at least one transistor in the amplifier to obtain a target bias current for the amplifier. The bias circuit may generate the at least one bias voltage based on either: a voltage across the inductor in the amplifier; a current through a current mirror formed with one of the at least one transistor in the amplifier; a gate-to-source voltage of one of the at least one transistor in the amplifier; a voltage in a replica circuit replicating the amplifier; or a current applied to the amplifier with a switched mode power supply disabled.
摘要:
PROBLEM TO BE SOLVED: To provide an operational amplifier, an analog arithmetic circuit and an analog-digital converter that have a compact output stage.SOLUTION: The operational amplifier of a folded cascode type includes: a constant current source for outputting a constant current; a differential input stage connected to the constant current source to output part of the output current of the constant current source as a differential current in accordance with a difference between voltages input into an inverting input terminal and a non-inverting input terminal; and the output stage connected in parallel with the differential input stage with respect to the constant current source to output as an output stage current a current remaining after subtracting the differential current from the output current of the constant current source. The output stage satisfies Ka=Iout/Idiff
摘要:
PROBLEM TO BE SOLVED: To provide a high frequency power amplifier apparatus whereby a high efficiency can be realized at a low power and the temperature characteristic can be improved also at the low power. SOLUTION: The high frequency power amplifier apparatus includes: a high frequency power amplifier transistor 2; a bias supply circuit 51 for supplying a bias current to the base of the high frequency power amplifier transistor; and a bias control circuit 52 connected between the base of the high frequency power amplifier transistor and the bias supply circuit, and the bias control circuit is connected to a power supply 32 of the high frequency power amplifier transistor. COPYRIGHT: (C)2007,JPO&INPIT