A driving circuit for a multi-channel EL light source

Abstract

The utility model provides a kind of driving circuit of multi-channel EL light source, including EL light source drive main control circuit and multi-channel EL light source circuit, the input end of EL light source drive main control circuit is connected with 5V constant voltage power supply, the output end of EL light source drive main control circuit is respectively connected with the drive of multi-channel EL light source circuit, EL light source circuit is equipped with EL light source LED1, EL light source circuit can receive external control signal, EL light source drive main control circuit can simultaneously power supply for multi-channel EL light source circuit, each EL light source circuit can control EL light source LED1 in itself circuit according to external control signal control bright and dark, the utility model has the beneficial effect that: it can realize one EL light source drive main control circuit drive multi-channel EL light source luminous, reduce manufacturing cost.

Description

TECHNICAL FIELD

[0001] The utility model relates to circuit technical field, concretely relates to a kind of driving circuit of multiway EL light source. BACKGROUND

[0002] EL light source is a kind of cold light source generated by electric field excitation, also called electric field luminescence. EL light source is through the voltage produced by electric field of two electrodes, and the electron of the electron of the electric field excitation collides with the light center, and causes the transition, change, recombination of electron between energy level, which leads to the light of a physical phenomenon. EL light source has high luminous efficiency, low power consumption, shockproof, and does not need to be maintained. It belongs to cold light source, and the color is very uniform. Compared with the unevenness of ordinary LED backlight, the most obvious advantage of EL light source backlight is that its light can be more evenly distributed on the entire screen. In addition, EL light source is also more energy-saving. The disadvantage of using EL light source is low brightness, short service life (generally 3000-5000h), and slight noise may occur when lighting EL light source.

[0003] EL light source is widely used in backlight, decoration and other fields due to its flat light source characteristics. However, due to its light-emitting characteristics, a specific driving IC is required to generate high-voltage alternating current for driving. Thus, the existing circuit for simultaneously driving multiple EL light sources has high cost, and each EL light source requires a driving circuit and a driving IC, which further leads to high use cost for people and poor use experience. UTILITY MODEL CONTENT

[0004] To solve the problems in the prior art, the utility model provides a kind of driving circuit of multiway EL light source, by being arranged in the driving circuit of multiway EL light source EL light source driving main control circuit and multiple EL light source circuit that cooperate with each other, EL light source driving main control circuit can simultaneously power supply multiple EL light source circuit, and each EL light source circuit can control the light-off of EL light source LED1 in itself circuit according to external control signal, can realize that one EL light source driving main control circuit drives multiple EL light source to emit light, only one EL light source driving IC can control multiple EL light source to emit light, reduce the manufacturing cost of the circuit for driving multiple EL light sources, greatly improve the use experience of user, solve the problem of high manufacturing cost of the circuit for simultaneously driving multiple EL light sources in the prior art.

[0005] This utility model provides a driving circuit for a multi-channel EL light source, including an EL light source driving main control circuit and a multi-channel EL light source circuit. The input terminal of the EL light source driving main control circuit is connected to a 5V constant voltage power supply, and the output terminal of the EL light source driving main control circuit is respectively connected to the driving circuits of the multiple EL light sources. Each EL light source circuit is equipped with an EL light source LED1. The EL light source circuit can receive external control signals, and the EL light source driving main control circuit can simultaneously supply power to the multiple EL light source circuits. Each EL light source circuit can control the lighting of its own EL light source LED1 according to the external control signal.

[0006] This utility model is further improved in that the EL light source driving main control circuit is provided with an EL light source driving chip U1. The EL light source driving chip U1 has 8 pins. The first pin of the EL light source driving chip U1 is connected to a 5V constant voltage power supply. The seventh and eighth pins of the EL light source driving chip U1 are connected to the EL light source circuit driving connection.

[0007] This utility model is further improved by including a field-effect transistor Q1, a field-effect transistor Q2, resistors R5 and R6, a transistor Q3 and Q4, resistors R7 and R8 in the EL light source circuit. The drain of the field-effect transistor Q2 is connected to pin 8 of the EL light source driver chip U1, the source of the field-effect transistor Q2 is connected to the drain of the field-effect transistor Q1, the source of the field-effect transistor Q1 is connected to one end of the EL light source LED1, and the other end of the EL light source LED1 is connected to pin 7 of the EL light source driver chip U1. The gate of transistor Q2 is connected to one end of resistor R5, the other end of resistor R5 is connected to the collector of transistor Q4, the base of transistor Q4 is connected to one end of resistor R7, the gate of field-effect transistor Q1 is connected to one end of resistor R6, the other end of resistor R6 is connected to the collector of transistor Q3, the base of transistor Q3 is connected to one end of resistor R8, the other ends of resistor R7 and resistor R8 can receive external control signals, and the emitters of transistor Q3 and transistor Q4 are grounded.

[0008] In a further improvement of this invention, the EL light source circuit is further provided with diodes D1 and D2. The positive terminal of diode D1 is connected to the drain of the field-effect transistor Q2, the negative terminal of diode D1 is connected to the gate of the field-effect transistor Q2, the negative terminal of diode D2 is connected to the drain of the field-effect transistor Q1, and the positive terminal of diode D2 is connected to the gate of the field-effect transistor Q1.

[0009] This utility model is further improved, and the EL light source driver chip U1 is model HV857MG.

[0010] Compared with the prior art, the beneficial effects of this utility model are: it provides a driving circuit for multiple EL light sources, which is installed in a POS machine. By setting up a cooperating EL light source driving main control circuit and multiple EL light source circuits in the driving circuit for multiple EL light sources, the EL light source driving main control circuit can simultaneously supply power to multiple EL light source circuits. Each EL light source circuit can control the on / off state of its own EL light source LED1 according to external control signals. It can realize that one EL light source driving main control circuit drives multiple EL light sources to emit light. Only one EL light source driving IC is needed to control multiple EL light sources to emit light, which reduces the manufacturing cost of the circuit for driving multiple EL light sources, greatly improves the user experience, and solves the problem of high manufacturing cost of the circuit for simultaneously driving multiple EL light sources in the prior art. Attached Figure Description

[0011] To more clearly illustrate the solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0012] Fig. 1 This is a circuit block diagram of a driving circuit for a multi-channel EL light source according to the present invention.

[0013] Fig. 2 This is a circuit diagram of the EL light source driving main control circuit of this utility model;

[0014] Fig. 3 This is a circuit diagram of the EL light source circuit of this utility model. Detailed Implementation

[0015] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein in the specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this invention are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or accompanying drawings of this invention are used to distinguish different objects, not to describe a particular order.

[0016] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the present invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0017] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0018] like Figs. 1-3 As shown, this utility model provides a driving circuit for a multi-channel EL light source, including an EL light source driving main control circuit and a multi-channel EL light source circuit. The input terminal of the EL light source driving main control circuit is connected to a 5V constant voltage power supply, and the output terminal of the EL light source driving main control circuit is connected to the driving circuits of the multi-channel EL light source circuits. Each EL light source circuit has an EL light source LED1. The EL light source circuit can receive external control signals, and the EL light source driving main control circuit can simultaneously power multiple EL light source circuits. Each EL light source circuit can control the on / off state of its own EL light source LED1 according to the external control signal. In this embodiment, a set of dedicated EL light source driving chips U1 is included to generate + / -90V AC power to drive the EL light source LED1.

[0019] When LED_EN1 is low, the EL light source circuit aims to turn off LED1. When VA is +90V, due to the presence of diode D1, the voltage of VC1 is also approximately +90V. However, transistor Q3 is not conducting at this time, and the voltage of P_1 is basically the same as VC1. Therefore, MOSFET Q1 will not conduct, and the voltage of VC1 will not be transmitted to VD1. There is no significant voltage difference across LED1, so LED1 will not light up. When VA is -90V, due to the presence of diode D1, the voltage of VD1 can be transmitted to VC1. However, due to the presence of diode D1, the voltage of N_1 is basically the same as VA. Therefore, MOSFET Q2 will not conduct, and the voltage of VC1 will not be transmitted to VA. There is no significant voltage difference across LED1, so LED1 will not light up.

[0020] When LED_EN1 is high, the circuit should enable the EL light source LED1 to turn on.

[0021] When VA is +90V, due to the presence of diode D1, the voltage of VC1 is also approximately +90V. At this time, transistor Q3 is conducting, and its collector voltage is 0V. Because of the presence of diode D2 (the Zener diode), the voltage difference between VC1 and P_1 is approximately 10V, the voltage regulated by the Zener diode. MOSFET Q1 is also conducting, so the voltage of VD1 is also approximately +90V. Therefore, there is a high voltage difference across LED1, and LED1 will light up. When VA is -90V, due to the presence of diode D2, the voltage of VD1 can be transmitted to VC1. At this time, transistor Q4 is conducting, and its collector voltage is 0V. Again, due to the presence of diode D1, the voltage difference between N_1 and VA is approximately 10V, the voltage regulated by the Zener diode. MOSFET Q2 is also conducting, so the voltage of VD1 is also approximately -90V. Therefore, there is a high voltage difference across LED1, and LED1 will light up. The LED_EN1 signal can control the on / off state of LED1 in one EL light source circuit. Therefore, multiple LED_ENx signals can be used to control the on / off state of LED1 in multiple EL light source circuits. By managing the switching of each LED_ENx signal and relying on the afterglow effect of the human eye, it is possible to drive multiple EL light sources to independently turn on and off using a single EL light source drive main control circuit.

[0022] like Fig. 2 As shown, the EL light source driver main control circuit includes an EL light source driver chip U1, model HV857MG. The EL light source driver chip U1 has 8 pins. Pin 1 of the EL light source driver chip U1 is connected to a 5V constant voltage power supply. Pins 7 and 8 of the EL light source driver chip U1 are connected to the EL light source circuit driver. In this embodiment, the EL light source driver main control circuit is used to simultaneously power multiple EL light source circuits.

[0023] like Fig. 3As shown, the EL light source circuit also includes field-effect transistors Q1 and Q2, resistors R5 and R6, transistors Q3 and Q4, resistors R7 and R8. The drain of field-effect transistor Q2 is connected to pin 8 of the EL light source driver chip U1, the source of field-effect transistor Q2 is connected to the drain of field-effect transistor Q1, the source of field-effect transistor Q1 is connected to one end of the EL light source LED1, the other end of the EL light source LED1 is connected to pin 7 of the EL light source driver chip U1, the gate of field-effect transistor Q2 is connected to one end of resistor R5, the other end of resistor R5 is connected to the collector of transistor Q4, and the base of transistor Q4 is connected to resistor R7. One end of the resistor is connected to the gate of the field-effect transistor Q1, which is connected to one end of the resistor R6. The other end of the resistor R6 is connected to the collector of the transistor Q3, and the base of the transistor Q3 is connected to one end of the resistor R8. The other ends of the resistors R7 and R8 can receive external control signals. The emitters of transistors Q3 and Q4 are grounded. The EL light source circuit also includes diodes D1 and D2. The anode of diode D1 is connected to the drain of the field-effect transistor Q2, and the cathode of diode D1 is connected to the gate of the field-effect transistor Q2. The cathode of diode D2 is connected to the drain of the field-effect transistor Q1, and the anode of diode D2 is connected to the gate of the field-effect transistor Q1. In this embodiment, each EL light source circuit can control the on / off state of its own EL light source LED1 according to the external control signal.

[0024] As can be seen from the above, this utility model provides a driving circuit for multiple EL light sources, which is installed in a POS machine. By setting up a cooperating EL light source driving main control circuit and multiple EL light source circuits in the driving circuit for multiple EL light sources, the EL light source driving main control circuit can simultaneously supply power to multiple EL light source circuits. Each EL light source circuit can control the on / off state of its own EL light source LED1 according to the external control signal. It can realize that one EL light source driving main control circuit drives multiple EL light sources to emit light. Only one EL light source driving IC is needed to control multiple EL light sources to emit light, which reduces the manufacturing cost of the circuit for driving multiple EL light sources, greatly improves the user experience, and solves the problem of high manufacturing cost of the circuit for simultaneously driving multiple EL light sources in the prior art.

[0025] The specific embodiments described above are preferred embodiments of this utility model, and are not intended to limit the specific scope of this utility model. The scope of this utility model includes but is not limited to the specific embodiments described above. All equivalent changes made in accordance with this utility model are within the protection scope of this utility model.

Claims

1. A driving circuit for a multi-channel EL light source, characterized in that: The system includes an EL light source driving main control circuit and multiple EL light source circuits. The input terminal of the EL light source driving main control circuit is connected to a 5V constant voltage power supply, and the output terminal of the EL light source driving main control circuit is connected to drive multiple EL light source circuits respectively. Each EL light source circuit is equipped with an EL light source LED1. The EL light source circuit can receive external control signals, and the EL light source driving main control circuit can simultaneously supply power to multiple EL light source circuits. Each EL light source circuit can control the on / off state of its own EL light source LED1 according to the external control signal.

2. The driving circuit for the multi-channel EL light source according to claim 1, characterized in that: The EL light source driving main control circuit is equipped with an EL light source driving chip U1. The EL light source driving chip U1 has 8 pins. The first pin of the EL light source driving chip U1 is connected to a 5V constant voltage power supply. The seventh and eighth pins of the EL light source driving chip U1 are connected to the EL light source circuit driving connection.

3. The driving circuit for the multi-channel EL light source according to claim 2, characterized in that: The EL light source circuit also includes field-effect transistors Q1 and Q2, resistors R5 and R6, transistors Q3 and Q4, resistors R7 and R8. The drain of field-effect transistor Q2 is connected to pin 8 of the EL light source driver chip U1, and the source of field-effect transistor Q2 is connected to the drain of field-effect transistor Q1. The source of field-effect transistor Q1 is connected to one end of the EL light source LED1, and the other end of the EL light source LED1 is connected to pin 7 of the EL light source driver chip U1. The gate of field-effect transistor Q2... The base of transistor Q1 is connected to one end of resistor R5, the other end of resistor R5 is connected to the collector of transistor Q4, the base of transistor Q4 is connected to one end of resistor R7, the gate of transistor Q1 is connected to one end of resistor R6, the other end of resistor R6 is connected to the collector of transistor Q3, the base of transistor Q3 is connected to one end of resistor R8, the other ends of resistors R7 and R8 can receive external control signals, and the emitters of transistors Q3 and Q4 are grounded.

4. The driving circuit for the multi-channel EL light source according to claim 3, characterized in that: The EL light source circuit also includes diodes D1 and D2. The anode of diode D1 is connected to the drain of the field-effect transistor Q2, the cathode of diode D1 is connected to the gate of the field-effect transistor Q2, the cathode of diode D2 is connected to the drain of the field-effect transistor Q1, and the anode of diode D2 is connected to the gate of the field-effect transistor Q1.

5. The driving circuit for the multi-channel EL light source according to claim 4, characterized in that: The EL light source driver chip U1 is model HV857MG.

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