Abstract:
An antenna includes two planar coils that are mechanically disposed face to face and electrically connected in series. The antenna is mounted to a disposable consumer product (for example, a cartridge for use with an electronic cigarette). The antenna is configured to support near field communications with a reader circuit for purposes of authenticating use of the disposable consumer product.
Abstract:
A circuit includes a current controlled oscillator (CCO), and a charge pump circuit boosting a supply voltage to produce a charge pump output voltage at a charge pump output node in response to output from the CCO. A current sensing circuit includes a first resistor coupled between the charge pump output node and an output node, a first transistor having a first conduction terminal coupled to the charge pump output node through a second resistor, and a second conduction terminal coupled to an input of the CCO. A second transistor has a first conduction terminal coupled to the output node, a second conduction terminal coupled to a reference current source, and a control terminal coupled to the control terminal of the first transistor and to the second conduction terminal of the second transistor.
Abstract:
An amplifier stage of an LDO regulator circuit includes an amplifier stage that generates a drive signal in response to a first voltage difference an output voltage of the LDO regulator circuit and a reference voltage. A drive stage having a quiescent current consumption is configured to generate a control signal in response to the drive signal. The control signal is applied to the control terminal of a power transistor. A dropout detector senses whether the LDO regulator circuit is operating in closed loop regulation mode or in open loop dropout mode by sensing a second difference in voltage between the drive signal and the control signal. A quiescent current limiter circuit responds to the sensed second difference by controlling the quiescent current consumption of the drive stage, and in particular limiting current consumption when the LDO regulator circuit is operating in the open loop dropout mode.
Abstract:
A driving circuit for an electric motor including multiple windings includes a sensing circuit to sense motor winding currents. A motor rotation angle signal is generated from the sensed currents and motor control voltages are generated as a function of the motor rotation angle signal. The motor windings are driven with motor drive voltages obtained by injecting into the motor control voltages injection pulses. The sensed currents include both torque components and injection components. The motor rotation angle signal is generated as a function of the injection components of the sensed currents.
Abstract:
Disclosed is a method for testing touch screen displays during manufacture. A touch screen controller (TSC) is packaged, and the analog channels of the TSC are characterized, with resulting data being stored for later use. The TSC is programmed, and the touch screen display and TSC are packaged together. The touch screen display is tested using firmware in the TSC, enabling calculation of the inherent capacitances between force and sense lines of the touch screen display when connected to the TSC during operation. The testing involves, for each force and sense line pair, measuring an output signal generated by a receive channel of the TSC coupled to the sense line of that pair. Based upon the data gathered during characterization, and the signals measured during testing, the capacity of the touch screen display is then calculated.
Abstract:
A driving circuit for an electric motor including multiple windings includes a sensing circuit to sense motor winding currents. A motor rotation angle signal is generated from the sensed currents and motor control voltages are generated as a function of the motor rotation angle signal. The motor windings are driven with motor drive voltages obtained by injecting into the motor control voltages injection pulses. The sensed currents include both torque components and injection components. The motor rotation angle signal is generated as a function of the injection components of the sensed currents.
Abstract:
A voltage regulator is controlled to improve supply voltage rejection by cancelling an alternating component of a supply voltage signal that is capacitively coupled to a high-impedance node within the voltage regulator. This cancellation is done by capacitively coupling an inverted version of the alternating component to the high-impedance node to thereby substantially cancel the alternating component present on the high-impedance node. The high-impedance node may be a high-impedance voltage reference node of the voltage regulator.
Abstract:
A significant reduction of the amplitude of the transient response is obtained by keeping a low dropout regulator circuit in a closed loop condition. This is achieved by manipulation of the reference voltage level when an open loop condition arises due to a falling input voltage. In this case, the reference voltage level is tracked with the input voltage level, keeping the output voltage regulated. As a consequence, the power pass element of the regulator is not forced into the linear region (in the case of a MOSFET) or deep saturation (in the case of a bipolar transistor).
Abstract:
An embodiment of the disclosure relates to a voltage converter for supplying a semiconductor light source and having at least an input terminal connected to a power supply reference, namely an AC mains voltage reference, and an output terminal providing a current signal to said semiconductor light source, the converter being also connected to a voltage reference and comprising at least a step-down block inserted between a switching node and to the output terminal and connected to the voltage reference and an input block connected to the input terminal, as well as to a first input node and to a first output node of a control circuit, in turn connected to the switching node and to the voltage reference. The input block is a pre-regulator input block and comprises at least a switching component connected to the input terminal and to a capacitive block, in turn inserted between a second input node of the control circuit and the voltage reference, such a switching component having a control terminal connected to the first output node.
Abstract:
An electronic amplifier for driving a capacitive load may include first and second differential input terminals to receive an input signal, and first and second differential output terminals to provide a differential output signal. The amplifier may further include a first operational device having first and second differential inputs connected to the first and second differential input terminals, respectively, and an output connected to the first differential output terminal, and a second operational device having first and second differential inputs connected to the first and second differential input terminals, respectively, and an output connected to the second differential output terminal. The first and second operational devices may be operatively configured so that both the first and the second output terminals are at a same reference potential during periods in which a magnitude of differential output signal amplitude decreases.