Abstract: A multimode radio has: an antenna that transmits and receives calls via radio signals of a plurality of communication modes; receivers that convert the received radio signals to signals for particular communication modes; an incoming call notifying unit having a speaker, display, or vibrator that respectively output a different sound, display content, or vibration according to the current communication mode; and a control unit that controls operations, detects the receiver that has received a call signal, and controls the incoming call notifying unit according to the communication mode set in a currently active receiver. Different notification methods are preassigned for the different communication modes, and when an incoming call to the address of the multimode radio is detected, the communication mode of the detected call is identified and a user is notified of the call by the notification method that corresponds to the identified communication mode.

Abstract: A battery pack for containing a plurality of cells and being attached to an electronic device comprises a plurality of switches for switching connection status of the cells between parallel connection and series connection. In the case of a battery pack containing a first cell and a second cell, the battery pack comprises a first wire for connecting the positive pole of the first cell and the positive pole of the second cell, a second wire for connecting the negative pole of the first cell and the negative pole of the second cell, a third wire for connecting the negative pole of the first cell and the positive pole of the second cell, a first switch for connecting/disconnecting the first wire, a second switch for connecting/disconnecting the second wire, and a third switch for connecting/disconnecting the third wire. The cells are connected in series when high voltage is needed, and in parallel otherwise.

Abstract: A battery pack for containing a plurality of cells and being attached to an electronic device comprises a plurality of switches for switching connection status of the cells between parallel connection and series connection. In the case of a battery pack containing a first cell and a second cell, the battery pack comprises a first wire for connecting the positive pole of the first cell and the positive pole of the second cell, a second wire for connecting the negative pole of the first cell and the negative pole of the second cell, a third wire for connecting the negative pole of the first cell and the positive pole of the second cell, a first switch for connecting/disconnecting the first wire, a second switch for connecting/disconnecting the second wire, and a third switch for connecting/disconnecting the third wire. The cells are connected in series when high voltage is needed, and in parallel otherwise.

Abstract: In a speech control apparatus used in a folding telephone, a rotary switch detects the rotating angle of the hinge of the folding telephone and delivers a control signal indicative of the hinge rotating angle to a speech controller. The speech controller controls the level of the speech signal from a microphone. The speech controller suppresses the noise included in the speech signal based on the control signal. The speech controller suppresses the echo included in the speech signal by generating an echo replica in accordance with the control signal and a radio signal from the communication partner.

Abstract: An input amplifier circuit including a gate circuit for amplifying such as a NAND circuit or a NOR circuit, in which a signal to be amplified is input from a first input terminal and an operating state or an inoperative state is selected by an enable signal input to a second input terminal, and a switch circuit including a resistance part, which is connected between the first input terminal and the output terminal of the NOR circuit and is controlled by the enable signal. A first MOS transistor is connected between a direct current power source and the first input terminal and is controlled by the enable signal and a second MOS transistor is connected between the first input terminal and ground and is controlled by the enable signal. Hence, a time required for raising from the inoperative state up to the operating state is reduced.

Abstract: A saw-tooth waveform signal generating circuit (3) generates a saw-tooth waveform signal d in response to a timing signal b derived from a reference clock a. A voltage comparator (4) slices the saw-tooth waveform signal with a reference voltage to shape the waveform thereof, thereby producing a synthesizer output e having a rectangular waveform. A counter (5) adds or subtracts a predetermined value every time a reference clock arrives. The count of the counter (5) is converted to an analog value by a DAC (6) and then is applied to, for example, the saw-tooth waveform signal generating circuit as a bias. As a result, the voltage for causing the saw-tooth waveform signal to start rising or falling is manipulated to allow the voltage comparator to slice the saw-tooth waveform signal at any desired timing. Hence, a synthesizer output can be produced in any desired phase.

Abstract: For use in a time division multiple access system and comprising a signal processing circuit (14, 15) which is for processing a local signal into a data burst under control by a burst control pulse having a control pulse width (T1), an electronic circuit comprises a control part (12) responsive to a sequence of data signals to produce a data pulse comprising a particular signal (PS) previous to a data time slot (TS) having a time slot width equal to the control pulse width. In addition, the control part produces an additional control pulse in accordance with the data signal sequence. In accordance with the burst control and the additional control pulses, a signal generator (13) processes the data pulse into a processed signal to supply the processed signal as the local signal to the signal processing circuit. Preferably, the additional control pulse has a width (T2) which is equal to that of data pulse.

Abstract: A frequency synthesizer includes three subfrequency synthesizers: a first synthesizer generating a first subfrequency varying in units of a frequency step, a second synthesizer generating a second subfrequency varying in units of a frequency step being N times the first frequency step, and a third synthesizer generating a third subfrequency varying in units of the first frequency step. One output signal is obtained by mixing the first subfrequency and the second subfrequency. A second output signal is obtained by mixing the second subfrequency and the third subfrequency.