Electronic equipment synchronously controlling light emission from light emitting devices and audio control
Electronic equipment includes a processing unit which controls light emission from LEDs by referring to music data described in a music file such as a MIDI file. The processing unit controls light emission from the LEDs by detecting the occurrence of sound described in the music file. Light emission from the LEDs may be controlled in accordance with tone data and/or a track number included in the music file. Alternatively, light emission from the LEDs may be controlled in accordance with volume data.
1. Electronic equipment comprising:
a communication processing unit operative to detect an incoming call from outside;
a memory operative to store a music file describing music data;
a CPU operative to request playback of the music file stored in the memory in response to a signal, indicating the detection of an incoming call, from the communication processing unit;
an audio output unit provided with a speaker and a processing unit, the speaker being operative to output sound based on the music file when an instruction for playback is received from the CPU and the processing unit being operative to analyze the music file when an instruction for playback is received from the CPU; and
a light-emitting unit provided with a light-emitting device and a light-emission processing unit operative to control light emission from the light-emitting device in accordance with the result of analysis of the music file by the processing unit, wherein
the light-emitting unit comprises:
a constant-current circuit connected to the light-emitting device in series and operative to drive the light-emitting device with a current set by an instruction from the CPU;
a switch element operative to receive an instruction from the CPU and turn the current generated by the constant-current circuit on and off; and
a pulse width modulation circuit operative to modulate a signal for controlling on and off of the switch element by using pulse width modulation in response to an instruction from the CPU.
2. The electronic equipment according to claim 1 , wherein the light-emission processing unit controls light emission from the light emitting device in accordance with tone data included in the music file.
3. The electronic equipment according to claim 1 , wherein the light-emission processing unit controls light emission from the light emitting device in accordance with a track number included in the music file.
4. The electronic equipment according to claim 1 , wherein the light-emission processing unit controls light emission from the light emitting device in accordance with volume data included in the music file.
5. The electronic equipment according to claim 1 , wherein the constant current circuit comprises:
a transistor;
a resistor which has its one end grounded and the other end connected to the transistor; and
an operational amplifier which has its output terminal connected to a control terminal of the transistor, its non-inverting input fed a reference voltage and its inverting input fed a feedback input of a voltage occurring at the other end of the resistor.
6. The electronic equipment according to claim 5 , wherein the switch element is provided between the control terminal of the transistor and a ground potential.
7. The electronic equipment according to claim 1 , further comprising a boost circuit which supplies a drive voltage to the light emitting device.
8. The electronic equipment according to claim 1 , wherein the light emitting device is a light emitting diode.
9. The electronic equipment according to claim 1 , wherein the music file is described according to the MIDI standard.
10. Electronic equipment comprising:
a communication processing unit operative to detect an incoming call from outside;
a memory operative to store a music file describing music data;
a CPU operative to request playback of the music file stored in the memory in response to a signal, indicating the detection of an incoming call, from the communication processing unit;
an audio output unit provided with a speaker and a processing unit, the speaker being operative to output sound based on the music file when an instruction for playback is received from the CPU and the processing unit being operative to analyze the music file when an instruction for playback is received from the CPU; and
a matrix array of a plurality of scan lines and a plurality of data lines;
a matrix array of a plurality of light emitting devices provided at intersections of the plurality of scan lines and the plurality of data lines;
a drive voltage supplying unit which supplies a drive voltage to the plurality of scan lines sequentially;
a plurality of constant current circuits each of which is provided for a corresponding one of the plurality of data lines and which generates a constant current to feed through the light emitting device connected to the corresponding data line in response to an instruction from the CPU;
a plurality of switch elements each of which is provided for a corresponding one of the plurality of constant current circuits and which turns the current generated by the corresponding constant current circuit to on and off in response to an instruction from the CPU;
a plurality of pulse width modulation circuits each of which is provided for a corresponding one of the plurality of switch elements and which modulates a signal for controlling on and off time of the corresponding switch element by using pulse width modulation in response to an instruction from the CPU.
11. Electronic equipment comprising:
a communication processing unit operative to detect an incoming call from outside;
a memory operative to store a music file describing music data;
a CPU operative to request playback of the music file stored in the memory in response to a signal, indicating the detection of the incoming call, from the communication processing unit;
an audio output unit provided with a speaker and a processing unit, the speaker being operative to output sound based on the music file when an instruction for playback is received from the CPU and the processing unit being operative to analyze the music file when the instruction for playback is received from the CPU; and
a light-emitting unit provided with a light-emitting device and a light-emission processing unit operative to control light emission from the light-emitting device in accordance with a result of analysis of the music file by the processing unit, wherein the light-emitting unit comprises:
a current output terminal connected to the light-emitting device;
a first transistor and a resistor connected in series between the current output terminal and a ground terminal;
an operational amplifier operative to receive a reference voltage at its non-inverting input and receive, at its inverting input, a potential at a node connected to the first transistor and the resistor via a first switch;
a second switch provided between an output terminal of the operational amplifier and the gate of the first transistor;
a second transistor provided between a gate of the first transistor and the ground terminal;
a pulse width modulation circuit operative to output a pulse-width modulated control signal to the gate of the second transistor; and
a configuration circuit operative to output the reference voltage and turn the first and second switches on to generate a current being fed to the light-emitting device when the instruction for playback is received.