JPH046275Y2 - - Google Patents

Description

[Detailed description of the invention] Technical field to which the invention pertains The present invention relates to an individual selective calling receiver, and more particularly to an individual selective calling receiver having a battery saving function in which the voltage applied to the receiving section is periodically intermittent. .

Description of the Prior Art Conventionally, an individual selective calling receiver having a battery saving function that periodically controls the power supply of the receiving section on and off uses a control signal a output from a decoder section 2 as shown in FIG. The switching transistor 4 was switched, the output of the constant voltage power supply section 5 was turned on and off, and the power supply to the reception section 1 was controlled. Further, in the second conventional example, as shown in FIG. 2, the switching transistor 4 is connected between the battery 6 and the constant voltage power supply section 5, and the power supply to the constant voltage power supply section 5 is controlled. Ta. In these first and second conventional examples, the minimum usable voltage V _BMIN of the battery power source is expressed by the following formula.

V _BMIN = V _OPMIN +V _CE(sat) +V _STBMIN where V _OPMIN is the minimum operating voltage of receiver 1,
V _CE(sat) is the saturation voltage of the switching transistor 4, and V _STBMIN is the minimum voltage drop in the constant voltage power supply section 5.

In the above equation, the usable voltage of the battery is higher than the minimum usable voltage of receiver 1 by V _CE(sat) +V _STBMIN , and for this reason, the battery life is limited in individual selective paging receivers that use batteries as a power source. It has the disadvantage that it becomes shorter. In addition, if the minimum usable voltage of the battery is determined from the viewpoint of battery life, the circuit of the receiving section should be
It must be designed to operate at voltages as low as V _CE(sat) + V _STBMIN . This makes it difficult to design, and the low voltage makes it vulnerable to changes in constants, environment, etc.

In addition, the saturation voltage of the switching transistor 4
In order to reduce V _CE(sat) , a transistor with a small collector resistance, that is, a large size, is required, which is extremely difficult to integrate into an IC, and therefore, a discrete transistor is always required to reduce the chip size. There were flaws.

Purpose of the invention The purpose of the invention is to eliminate unnecessary voltage drops, extend battery life, eliminate the need for discrete transistors, and further reduce power consumption to extend battery life. The aim is to provide the opportunity.

Structure of the invention The present invention connects a constant voltage power supply section between the voltage source and the receiving section, directly controls the voltage section with a control signal for battery saving from the decoder section, and furthermore, connects the constant voltage power supply section between the voltage source and the receiving section. a voltage supply transistor in which a collector/emitter path is inserted in series in the power supply path from the voltage source to the decoder section, a control transistor whose conduction/non-conduction is controlled by the control signal, and this control transistor. means for generating a reference voltage based on the current flowing through the circuit element when the control transistor is turned on, including a circuit element connected between the circuit element and the voltage source; The present invention is characterized in that it comprises means for generating a corresponding feedback voltage, and a differential amplifier that controls the degree of conductivity of the voltage supply transistor based on the reference voltage and the feedback voltage.

According to this configuration, since the switching transistor 4 shown in FIGS. 1 and 2 is omitted, unnecessary voltage drop does not occur and a discrete component such as the transistor is not required. When the control transistor is non-conductive due to the saving control signal, no reference voltage is generated, so no power consumption occurs in the constant voltage power supply unit itself, and the battery life is further extended.

Embodiments Next, embodiments of the present invention will be described with reference to the drawings. A first embodiment is shown in FIG. In FIG. 3, when the battery saving control signal a from the decoder section 2 is High, the control transistor 10 is turned on, current flows through the resistors 11, 12, 16 and the transistors 13, 14, 15, and other Current also flows through the transistor, and the reference voltage V1 is applied to the base of the transistor 19. In the differential amplifier consisting of transistors 17, 18, 19, 20, and 21, the reference voltage V ₁ and the feedback voltage V ₂
The transistors 23 and 24 are controlled by the output of the differential amplifier, and a stabilized output voltage V ₀ is supplied to the receiver 1. In this case, the output voltage V ₀ is set by V ₀ =I ₁ R ₁ +V ₁ .
Next, when the battery saving control signal a from the decoder section 2 is Low, the control transistor 10 is turned off and the reference voltage _V1 becomes O _V. Further, the constant currents I ₀ and I ₁ generated by the transistors 21 and 25 also become O, and the transistor 24 is turned off. Therefore, the output voltage V ₀ becomes O _V and no power is supplied to the receiving section 1 .

In the second embodiment, as shown in FIG. 4, the transistors 21 and 25 in FIG. 3 are replaced with resistors 28 and 29. In this case, the output voltage V ₀ is V ₀ =R ₁ +R ₂ / It is set as R ₂ ×V ₁ .

Effects of the invention As explained above, this invention reduces the number of components and eliminates unnecessary voltage drops by directly controlling the circuit operation of the constant voltage power supply section using the battery saving control signal from the decoder section. , it also has the effect of further reducing power consumption and greatly extending battery life.

[Brief explanation of the drawing]

1 and 2 are circuit diagrams showing the conventional configuration, FIG. 3 is a circuit diagram showing the configuration of the first embodiment, and FIG. 4 is a circuit diagram showing the configuration of the second embodiment. . In the figure, 1... Receiving section, 2... Decoder section, 3... Speaker, 4... Switching transistor, 5... Constant voltage power supply section, 6... Battery,
10...Control transistor, 11, 12, 1
6, 26, 28, 29...Resistance, 13, 14, 1
5, 17, 18, 19, 20, 21, 22, 2
3, 24, 25...transistor, 27...capacitor, a...control signal.

Claims (1)

[Scope of utility model registration request] A voltage source 6, a decoder section 2 that receives power supply from the voltage source 6 and generates a control signal a whose logic level changes periodically, a receiver section 1 that supplies a demodulated signal to the decoder section 2, and the voltage source. 6 and the receiving section 1, the constant voltage power supply section 5 is connected between the receiving section 1 and the receiving section 1, and controls the power supply to the receiving section 1 in response to the control signal a. A voltage supply transistor 24 having a collector-emitter path inserted in series in the power supply path from 6 to the receiving section 1, and a control transistor 10 whose conduction/non-conduction is controlled according to the logic level of the control signal a. and a circuit element 11- connected between this control transistor 10 and the voltage source 6.
means 11 for generating the reference voltage V ₁ based on the current flowing through the circuit element 11-13 when the control transistor 10 is turned on;
-16, means 14, 22, 25 for generating a feedback voltage V ₂ according to the voltage supplied to the receiving section 1;
26; 26, 29; and a differential amplifier 17-23 that controls the conductivity of the voltage supply transistor 24 based on the reference voltage _V1 and the feedback voltage _V2 . .