JPS59127436A - Integrated circuit with mixing function of singing signal - Google Patents

Abstract

PURPOSE:To reduce external attachment parts and terminals in number by applying directly a singing current which is generated by a current generation part controlled by a singing signal to a voice preamplifier part. CONSTITUTION:A signal received by a receptor part 1 is applied to a preamplifier 2 and a decoder part 8, and when the decoder 8 detects a call number, a singing signal (a) is generated. When a singing detection part 11 detects the singing signal (a), singing is stopped for a specific time. When the singing is generated, an input control signal (d) is applied from an input control signal generation part 13 to an input control part 10 to limit the application of the output signal from the reception part 1 to the voice preamplification part 2. On the other hand, when the singing is applied to the singing current generation part 14, a singing current (e) corresponding to the singing signal (a) is generated. This singing current (e) is applied to the output terminal of the voice preamplification part 2 to generate a signal voltage having the same shape with the singing signal (a).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention receives and demodulates a radio modulated wave consisting of a selective call signal and voice information, decodes its own selective call signal, and then notifies the call with a ringing sound for a certain period of time, and then continuously transmits voice information. The present invention relates to an integrated circuit for mixing ringing signals of an individual selective call receiver having a function of transmitting.

Conventionally, in an integrated circuit for mixing sound signals of an individual selection discharge receiver which has a calling function by sound generation and a function of transmitting information by voice, as shown in FIG. The generated sound signal was applied to the pre-audio amplification unit 2 through the coupling capacitor 16, but according to this, when integrating the sound signal into an integrated circuit, the coupling capacitor 16 is required for the sound signal input signal B and external installation. There were drawbacks.

The present invention connects a current source controlled by the sound signal to the output resistor of the pre-sound amplifier without mixing the sound signal with a coupling capacitor, and directly transmits the sound signal to the pre-sound amplifier. An object of the present invention is to provide an integrated circuit for mixing a sound signal, which makes it possible to reduce the number of externally attached parts and the number of terminals.

According to the present invention, the output current of the current generating section consisting of a current source that is intermittently controlled by a sound signal and a resistor that sets the magnitude of the current value of this current source is transmitted to the prefix audio that includes an output resistance. A sound signal mixing integrated circuit is obtained, which is characterized in that it is directly connected to the output point of the amplifier section.

Next, the operating principle of the present invention will be explained using examples. In FIG. 2, the signal received by the receiving section 1 is applied to the pre-audio amplifier section 2 and the decoder section 8, and when the calling number is identified by the decoder section 8, the signal is generated by the ringing signal generating section 9 into a square wave. A sound signal (a) is generated, and this sound signal (a
) is added to the sound current generating section 14 and the sound detection section 11.

When the sound signal (a) is detected by the sound detection section 11, it is added to the sound generation time setting section 12, and after a certain period of time (T1), a sound stop signal (C) is sent to the sound generation time setting section 12. The sound is generated by the sound generating section 9, and the sound stops.

Note that when the sound is generated (T1), the input control signal (d) is applied from the input control signal generation section 13 to the input control section 10,
The output signal from the receiver 1 is restricted from being applied to the preamplifier 2.

On the other hand, when the sound signal (a) is applied to the sound current generating section 14, a sound current (e) corresponding to the sound signal (a) is generated. This sounding current (e) is applied to the output terminal of the preamplifier 2, and a signal voltage having the same shape as the sounding signal (a) is generated there.

In FIG.
After being applied to the inverting section 21 at , it is applied to the base of the current interrupting transistor 23 .

When the inverted sound signal (a) is “Lo”, the current setting resistor 2
2 The voltage generation transistor 24 and the current generation transistor 25 generate a noise current (e) of the magnitude A=(VCC''BE)/R2□ in the collector of the current generation transistor 25.This noise current (e) is applied to the collector of the output transistor 27 of the preamplifier 2, and a sound output voltage of a magnitude of ■A: IAXR26 is generated at this collector. The magnitude of the sound output signal is controlled by the current setting resistor 26. When the inverted sound signal ('1ll) is l-1', the current generation transistor 25 becomes an inactive region. , the sound current (e) becomes 0.Furthermore, the output impedance of the current generating transistor 25 in this case is extremely large;
The operation of the preamplifier 2 is not affected.

Further, the collector potential of the transistor 27 is different when the input control signal (d) is "H" and when it is L. Therefore, by using a differential amplifier in the phase conversion section 3, changes in the DC potential applied to the power amplification sections 4 and 5 at the subsequent stage are eliminated. The waveforms of ta) to te) described above are shown in FIG.

From the above explanation, it is clear that the present invention is capable of applying the sound current generated by the current generating section 14 controlled by the sound signal (a) directly to the preamplifier section 2, thereby achieving an improvement over the conventional example. It is possible to eliminate the coupling capacitor 16 and the large sound output terminal B shown in FIG. is effective.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a conventional embodiment, Fig. 2 is a block diagram showing an embodiment of the present invention, Fig. 3 is a waveform diagram of each part in an embodiment of the present invention, and Fig. 4 is a block diagram showing an embodiment of the present invention. It is an example of a circuit of the sounding current generating section 14 of the invention. In the figure, 1...receiving section, 2...marked pre-sound amplification section, 3...phase conversion section, 4, 5...
... Power amplification section, 6 ... Gain adjustment resistor, 7 ... Bypass capacitor, 8 ...
・Decoder section, 9...Sound signal generation section, 10.
...Input control section, 11... Sound detection section,
12... Sound generation time setting section, 13...
- Input control signal generation section, 14... Sound current generation section, 15... Speaker, 21... Inversion section, 22... Current setting resistor Vessel, 23...
... Transistor for current intermittent, 24 ... Transistor for voltage generation, 25 ... Current. Generation transistor, 26...output load resistance,
27... Output transistor, 28, 29...
... Phase conversion stage transistor, 30 ... Sound signal mixing integrated circuit, (a) ... Sound signal, (
b)... Sound detection signal, (C)... Sound stop signal, (d)... Input control signal, (e)
... Sound current, A ... Audio signal input terminal, B, e ... Sound signal input terminal.

Claims (1)

[Claims] An integrated circuit used in an individual selective call receiver that receives and demodulates a radio modulated wave consisting of a selective call signal and voice information, and when it decodes its own call signal, generates an alarm sound for a certain period of time and continuously broadcasts voice information. , a current generating transistor that is intermittently controlled by an output signal of an external sound signal generating section; a current setting resistor that determines the magnitude of the current of the current generating transistor; and a current setting resistor that determines a voltage by applying the current. 1. An integrated circuit having a sound signal mixing function, characterized in that the integrated circuit has a voltage amplifier including a resistor for producing a sound signal.