JPS62234193A - Driving circuit for light emitting element - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a driving circuit for a light emitting element suitable for use as a reception display in a selective call receiving device.

2. Description of the Related Art Conventional selective call receiving devices use displays such as LEDs that are driven by demodulating the received selective call signal in a radio section and a decoder section and matching it with the own call signal stored in a memory. For example, the decoder section outputs a blinking signal for the LED, and as shown in FIG. LED voltage VB
The voltage was increased to enough voltage to drive the LED 6, and the LED 6 blinked to notify that there was a call.

Problems to be Solved by the Invention However, in the above-mentioned conventional selective call receiving device, when a plurality of individual call numbers are provided and it is desired to display which individual number has been called, the number of drive circuits 1 is Therefore, a plurality of choke coils 5 are required. Therefore, especially for applications where space is extremely limited such as a selective call receiving device, choke coils 5 are required.
There were problems such as not having enough storage space.

The present invention eliminates the drawbacks of the conventional example, and the choke coil 5
It is an object of the present invention to provide a driving circuit for a light emitting element that can drive at least one light emitting element.

Means for Solving the Problems In order to achieve the above object, the present invention aims to boost the power supply voltage and drive output using a flashing signal common to a plurality of individual call numbers when a plurality of light emitting elements are operated in one motion. The light emitting device is configured to selectively light up any one of the plurality of light emitting devices using an identification signal that differs depending on the individual call number.

Accordingly, according to the present invention, as is clear from the above configuration,
It is possible to share a driving circuit for a plurality of light emitting elements, and therefore, it is possible to reduce the number of choke coils, which are large components.

EXAMPLES Below, examples of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 shows a first embodiment, ! 12, ll
b is a light-emitting tie with a plurality of light-emitting elements,
12 to 15 are transistors, 16 to 19 are resistors, 20 is a choke coil 21, an input terminal for blinking signal A, and 22 is an input terminal for identification signal B.

With the above configuration, when the radio section of the selective call receiving device receives the calling number of its own machine, the decoder section outputs the alternating current light emitting diode blinking signal A, which is input to the input terminal 21, and which calling number is received. An identification number B indicating whether or not the user has done so is input to the input terminal 22. The identification number B becomes HI GI-I or LOW corresponding to the two calling numbers.

When a HIGH signal is input, the transistor 15 is turned off because this signal is applied to the base via the resistor 18. Further, the transistor 14 is turned on because a signal inverted by the resistor 17 and the transistor 13 is applied via the resistor 19. On the other hand, in response to a LOW signal, transistor 15 is turned on, and transistor 14 is turned on.
becomes OFF. On the other hand, since the blinking signal A is an alternating current, the power supply voltage (for example, 1
．． 5 V) is switched boosted and amplified and commonly applied to the anodes of the light emitting diodes lla, llb. Therefore, the light emitting diode llb lights up for the HIGH identification signal B1, and the light emitting diode lla lights up for the LOW identification signal.

FIG. 2 shows the configuration of a second embodiment, and the same symbols as in FIG. 1 represent the same names. Reference numeral 21 denotes a two-color light emitting diode, which has a common anode terminal 9 and cathode terminals (a) and (c) which are individually driven by transistors 15 and 14, respectively. In the second embodiment, since two diodes are actually enclosed in - number of light emitting diodes,
This has the advantage that space accuracy is further improved.

In addition, in the above configuration, the boost amplification means is formed by the transistor 12, the choke coil, etc., and the transistors 13 to 1
5 and the like form a selection means. Furthermore, although the above two embodiments both use two light emitting elements, this can be easily expanded to three or more.

Effects of the Invention As is clear from the above embodiments, the present invention, when driving a plurality of light emitting elements corresponding to different individual numbers in a selective call receiving device, inputs a common blinking signal to a transistor to power the transistor. Since the voltage is boosted and applied to the light-emitting display, and one of the plurality of light-emitting elements is selected using an individual identification signal, the choke coil of the drive circuit can also be used, and therefore a single selective call receiving device can be used. This has the advantage that a plurality of light emitting elements can be individually lit for each individual number of the own machine.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a light emitting element driving circuit in a first embodiment of the present invention, FIG. 2 is a block diagram of a second embodiment,
FIG. 3 is a block diagram of a conventional light emitting element driving circuit. 11a, llb... light emitting diode, 12-15
...Transistor, 16-19...Resistor, 20...
・Choke coil, A, B...input terminal. Name of agent: Patent attorney Toshio Nakao (1st person)
Figure υn Figure 2 Figure 3!

Claims (1)

[Claims] When the machine is called by one of the plurality of call numbers unique to the own machine, a common AC blinking signal is input and the power supply voltage is boosted and amplified by a boost amplification means using a choke coil. a selection means for applying a common voltage to a plurality of light emitting elements corresponding to a plurality of calling numbers, and inputting a different identification signal for each of the calling numbers to select a corresponding light emitting element from the plurality of light emitting elements; Drive circuit for light emitting elements.