摘要:
A portable electronic device such as a mobile telephone is powered by a battery and is arranged to operate in an off-mode, a standby mode and an on-mode of operation. Primary electronic circuitry, operable only during the on-mode, provides the main features of the device. Secondary electronic circuitry is operable during the off-mode, and standby circuitry is operable during the standby mode. A power supply circuit is arranged for coupling to the battery in order to provide power to the electronic device during the on-mode. A secondary power source is arranged to be charged by the power supply circuit during the on-mode and further arranged for providing power to the second electronic circuitry during the off-mode. The secondary power source is further arranged for providing power to the standby circuitry during the standby mode, such that the power supply circuit does not operate during the standby mode.
摘要:
A sample and hold demodulator circuit for use in an automotive immobiliser to recover modulation information from a received modulated carrier signal (V RD ), the circuit comprising: sample and hold means for sampling the received signal to recover the modulation information therein, and control means (214) coupled to the sample and hold means for controlling operation thereof, the control means comprising shift register means (252) for receiving the received signal (V RD ) and for producing at its outputs signals (SAMPLE, SAMPLE2, LATCH) for controlling operation of the sample and hold means. The circuit provides a single IC solution, allowing amplitude and phase demodulation to be performed with a single sample and hold circuit without requiring a dedicated microcontroller or extra interfaces or wires to a main electronic control unit elsewhere in the automobile.
摘要:
A sequence generator 10 for a frequency synthesiser 1,2,3,4,5,10 forming part of a direct modulator comprises an input 10a for receiving an input multibit signal X(z), an output 10c for outputting an output digital signal Y(z) and sequence generation means 10b. The sequence generation means is adapted to produce a noise transfer function which has a minimum value both at the frequency corresponding to the dc component of the input signal and at one or more frequencies away from the frequency corresponding to the dc component of the input signal.
摘要:
A portable electronic device such as a mobile telephone is powered by a battery and is arranged to operate in an off-mode, a standby mode and an on-mode of operation. Primary electronic circuitry, operable only during the on-mode, provides the main features of the device. Secondary electronic circuitry (70) is operable during the off-mode, and standby circuitry (60) is operable during the standby mode. A power supply circuit is arranged for coupling to the battery (5) in order to provide power to the electronic device during the on-mode. A secondary power source (75) is arranged to be charged by the power supply circuit during the on-mode and further arranged for providing power to the second electronic circuitry during the off-mode. The secondary power source is further arranged for providing power to the standby circuitry during the standby mode, such that the power supply circuit does not operate during the standby mode.
摘要:
An insulated gate bipolar transistor having a collector electrode 3, an emitter region 6 and a base region 4 formed between the collector electrode and the emitter region, further including a channel stop region 17 spaced from the emitter region and electrically connected to the collector electrode. The base region 4 includes a first region 4c between the emitter region and the channel stop region and a second region between the first region and the collector electrode, the first region having a higher minority-carrier-lifetime than the second region, whereby the first region provides a conductivity modulated conduction path between the emitter region and the channel stop region when the insulated gate bipolar transistor is reverse biased.
摘要:
A stall detection circuit (50) for a motor having a coil (52) through which a current signal flows comprises measuring circuitry (70) for measuring regularly a time duration (Tr) of a predetermined phase of the current signal through the coil, which is preferably a recirculation phase, comparison circuitry (72) for comparing the measured time durations, and logic circuitry (74) for providing an indication of stall when a comparison result from the comparison circuitry (72) corresponds to a predetermined pattern.
摘要:
A surface mount semiconductor diode device (50) having first (51) and second (53) coplanar contacts comprises a semiconductor element (52) having a first surface electrically mounted on a first member (54) formed of conductive material, which first member (54) has an arm (58) extending in a direction away from the semiconductor element (52) to an end (60) which forms the first contact (51). A cup member (62) formed of conductive material comprises a wall (64) extending from a bottom portion (66) so as to form an opening (68) surrounded by the wall (64). The semiconductor element (52) and first member (54) are mounted within the opening (68) such that a second surface of the semiconductor element (52) is electrically coupled to the bottom portion (66) of the cup member (62) and the end of the arm (58) extends above a top surface (72) of the wall (64). The cup member (62) further comprises a leg portion (74) integral with and extending from the top surface of the wall (64) such that an end (76) of the leg portion (74) is coplanar with the end of the arm, and forms the second contact (53).