摘要:
A method of controlling a phase locked loop in a mobile station and a mobile station of a cellular telecommunications system are provided. The mobile station comprises an integrated phase locked loop for generating output frequencies; a frequency control unit for providing a frequency control word for the phase locked loop, according to which frequency control word an output frequency is generated; and a tuning unit for providing a synchronized tuning word for the phase locked loop, the tuning unit being configured to output the synchronized tuning word to the phase locked loop in synchronization with the output of the frequency control word. The invention reduces the settling time of a mobile station when an operating frequency is changed from one to another.
摘要:
A method of controlling a phase locked loop in a mobile station and a mobile station of a cellular telecommunications system are provided. The mobile station comprises an integrated phase locked loop for generating output frequencies; a frequency control unit for providing a frequency control word for the phase locked loop, according to which frequency control word an output frequency is generated; and a tuning unit for providing a synchronized tuning word for the phase locked loop, the tuning unit being configured to output the synchronized tuning word to the phase locked loop in synchronization with the output of the frequency control word. The invention reduces the settling time of a mobile station when an operating frequency is changed from one to another.
摘要:
A circuit includes a differential amplifier having a first input for coupling to a first terminal of a microphone and a second input for coupling to a first terminal of a component having an impedance value that is substantially equal to an impedance value of the microphone, where a second terminal of the microphone and a second terminal of the component are coupled to circuit ground. The circuit further includes a first resistance having a first node coupled to a source of microphone bias voltage and a second node coupled to the first terminal of the microphone; and a second resistance having a first node coupled to the source of microphone bias voltage and a second node coupled to the first terminal of the component. Operation of the differential amplifier results in attenuating or suppressing common mode noise and interference present in the microphone bias voltage and in the common potential.
摘要:
A method of tuning a station is disclosed, wherein a first pilot signal is applied on a circuit of the station and the resulting output power of the signal circuit is subsequently detected. A second pilot signal is then applied to the circuit and the resulting output power of the circuit is detected. The offset of the circuit is then tuned based on information of the resulting output power detected for the first and second signals. A station that is adapted to implement the method may be tuned by the manufacturer thereof or later after having already been taken into use. The tuning may occur automatically as response to a predefined event.
摘要:
A method of using an integrated circuit with at least one defect, said method comprising the steps of determining the location of one or more defects in said integrated circuit; selecting a program to be stored on said integrated circuit, said program being selected on the basis of the location of said one or more defects; and loading said program onto said integrated circuit.
摘要:
A method of controlling a phase locked loop in a mobile station and a mobile station of a cellular telecommunications system are provided. The mobile station comprises an integrated phase locked loop for generating output frequencies; a frequency control unit for providing a frequency control word for the phase locked loop, according to which frequency control word an output frequency is generated; and a tuning unit for providing a synchronized tuning word for the phase locked loop, the tuning unit being configured to output the synchronized tuning word to the phase locked loop in synchronization with the output of the frequency control word. The invention reduces the settling time of a mobile station when an operating frequency is changed from one to another.
摘要:
A circuit includes a differential amplifier having a first input for coupling to a first terminal of a microphone and a second input for coupling to a first terminal of a component having an impedance value that is substantially equal to an impedance value of the microphone, where a second terminal of the microphone and a second terminal of the component are coupled to circuit ground. The circuit further includes a first resistance having a first node coupled to a source of microphone bias voltage and a second node coupled to the first terminal of the microphone; and a second resistance having a first node coupled to the source of microphone bias voltage and a second node coupled to the first terminal of the component. Operation of the differential amplifier results in attenuating or suppressing common mode noise and interference present in the microphone bias voltage and in the common potential.
摘要:
A method of tuning a station is disclosed, wherein a first pilot signal is applied on a circuit of the station and the resulting output power of the signal circuit is subsequently detected. A second pilot signal is then applied to the circuit and the resulting output power of the circuit is detected. The offset of the circuit is then tuned based on information of the resulting output power detected for the first and second signals. A station that is adapted to implement the method may be tuned by the manufacturer thereof or later after having already been taken into use. The tuning may occur automatically as response to a predefined event.
摘要:
A wireless communications mobile station (10) includes at least one antenna (240) and a RF transceiver (210,220) containing a direct conversion receiver (1) coupled to the antenna. The direct conversion receiver contains a low noise amplifier (3) for amplifying a received RF signal and for outputting the amplified RF signal to a current switching down-conversion mixer (4). The down-conversion mixer has a first input node for receiving the amplified RF signal, a second input node for receiving a local oscillator (LO) signal for mixing with the amplified RF signal and an output node coupled to an input of an operational amplifier forming a low pass filter (5A). In accordance with an aspect of this invention the low pass filter has a low pass pole generated by a resistor R and a capacitor C coupled in parallel in a feedback path of the operational amplifier, where a low pass comer frequency of the low pass filter is inversely proportional to the product of R and C. In a preferred embodiment at least the down-conversion mixer and the low pass filter are implemented as part of an integrated circuit, and the resistor and the capacitor are fabricated within the integrated circuit.
摘要:
A wireless communicator, such as a cellular telephone or personal communicator, includes a power source (e.g., two series connected batteries) providing output voltages VSS, VDD, and V1, where V1=(VDD-VSS)/2. The power source is coupled to a first load for powering the first load with VSS and VDD. The wireless communicator further includes a power source switching unit having first inputs coupled to VSS, VDD and V1, a second input coupled to a MODE signal, and outputs coupled to a second load. The power source switching unit is responsive to a first state of the MODE signal for powering the second load with VSS and V1, and is responsive to a second state of the MODE signal for powering the second load with V1 and VDD. By periodically toggling the MODE signal, such as at a frame rate of the wireless communicator, the power drawn from each battery by the second load is equalized, while providing the second load with a desired lower operating voltage. Also shown is interface circuitry for level shifting signals output from the first load to the second load, and signals output from the second load to the first load. The interface circuitry is also responsive to the state of the MODE signal for accommodating the changes in levels of the second load input/output signals between VSS-V1, and V1-VDD.