CN214376921U - Infrared signal receiving and transmitting circuit, chip and equipment - Google Patents

Abstract

The utility model provides an infrared signal transceiver circuit, it includes infrared diode and circuit function module, and circuit function module is the inside analog circuit of integrated circuit chip, and infrared diode passes through an IO interface and the circuit function module electricity of integrated circuit chip and is connected, and circuit function module is used for receiving inside control signal in order to realize infrared emission function, and be used for with the infrared receiving function is realized in the current signal amplification of infrared diode output. The utility model also provides an integrated circuit chip and infrared signal transceiver. Compared with the prior art, adopt the technical scheme of the utility model the infrared signal transceiver circuit has reduced the parasitic capacitance influence that the full integration exists to make the integrated level of the whole scheme that adopts this circuit high, the learning distance is far away and the learning effect is good.

Description

Infrared signal receiving and transmitting circuit, chip and equipment

Technical Field

The utility model relates to an integrated circuit design field especially relates to an infrared signal transceiver circuit, integrated circuit chip and infrared signal transceiver equipment that are applied to infrared remote controller of agreement self-learning type.

Background

At present, with the increasing variety of remote control equipment, universal remote controllers, intelligent voice remote controllers and Bluetooth remote controllers are increasingly popularized, and particularly, protocol self-learning remote controllers are more and more widely used, such as universal remote controllers, intelligent voice remote controllers and the like. The remote controller has a self-learning function, can receive information of other remote controllers in a learning mode, convert and store the information into the remote controller, and transmit an instruction under a designated key or voice signal, so that the functions of replacing the remote controller, upgrading voice control and the like are realized. The self-learning remote controller needs to have an infrared self-learning function more than a common remote controller, needs to realize infrared signal acquisition and identification, and the traditional scheme adopts an independent infrared receiving device, and an independent infrared receiving head has the function of infrared signal extraction and decoding, and output digital signals can directly enter the remote controller main control IC through an IO port, but the price is expensive. Therefore, the infrared emitting diode is multiplexed to be used as an infrared receiving device, and the realization of the photoelectric conversion of the infrared signal is the mainstream scheme of the self-learning remote controller in recent years.

The infrared signal transceiver circuit of the self-learning remote controller in the related art comprises an infrared emitting diode, a resistor, a power switch tube and a comparator. The infrared signal receiving and transmitting circuit controls the conduction and the disconnection of the infrared emitting diode by using the characteristic that infrared light is generated when the infrared emitting diode flows current, controls the current in the infrared emitting diode by using a power switch tube, is connected with the infrared emitting diode in parallel by using a resistor, and then compares the voltage change on the resistor with a reference signal by using a comparator to realize photoelectric conversion. Specifically, in an infrared emission state, the infrared signal receiving and transmitting circuit realizes electric light conversion; and when the infrared receiving state, the infrared signal receiving and transmitting circuit realizes the light-to-electricity conversion.

However, in the related art, the circuit module of the infrared signal transceiver circuit is generally a discrete circuit, and is not integrated inside one chip, and two independent IO ports are required for communication, so that more peripheral materials are provided in the overall scheme, the performance and index consistency of the circuit is low, the complexity of the PCB circuit is high, and the cost of the circuit scheme is high. When the infrared signal transceiver circuit receives the learning circuit mode, the circuit has the hidden problem that the learning distance is short or the infrared source strength has specific requirements in the learning distance. The infrared emitting diode has a different internal structure than the infrared receiving diode, the photoelectric sensitivity of the infrared emitting diode serving as a receiving tube is far lower than that of the infrared receiving diode, the photoelectric sensitivity of the infrared emitting diode serving as the infrared receiving diode is poorer, and the generated induced photocurrent is smaller. The photocurrent generated by the diode can be greatly reduced due to the increase of the distance of the infrared light source, parasitic capacitance exists in the parasitic capacitance of the infrared emitting diode, an external device or a comparator and the like, infrared self-learning is to monitor and learn infrared signals (32-56KHz) with carrier frequency, and the parasitic capacitance has the attenuation effect on alternating current signals. The rising and falling edges of the electrical signal and even the voltage amplitude are affected.

In addition, the infrared signal receiving and transmitting circuit adopts the resistance voltage and the reference voltage to compare through the comparator, when the infrared light intensity is reached (the distance is short), the resistance flows through larger current, faster voltage change edge and larger voltage amplitude can be generated, and the comparator can accurately convert. When infrared light is strong and weak (a distance is slightly far away), photocurrent is greatly reduced, the existence of parasitic capacitance can enable current flowing through a resistor to become smaller, a slow edge and a small voltage amplitude are generated on the resistor, so that the setting of the voltage value of the reference voltage is directly influenced, if the voltage value of the reference voltage is too low, the voltage cannot be identified by a comparator when the infrared distance is slightly far away, and the voltage value of the reference voltage is too high, and the voltage cannot be pulled up to the voltage value of the reference voltage by a resistor under the carrier frequency due to the attenuation effect of the parasitic capacitance, so that the comparator cannot identify. Therefore, the detection distance and parasitic consideration of the infrared signal transceiving circuit are limited, so that the infrared signal transceiving circuit has high dependency on the intensity of an infrared light source and the signal identification rate of the circuit is low.

Therefore, there is a need to provide a new circuit, chip and device to solve the above problems.

SUMMERY OF THE UTILITY MODEL

Not enough to above prior art, the utility model provides a reduce the parasitic capacitance influence that full integration exists to make the infrared signal transceiver circuit, integrated circuit chip and the infrared signal transceiver equipment that adopt the whole scheme of this circuit high, the learning distance is far away and the learning effect is good.

In order to solve the technical problem, the utility model provides an infrared signal transceiver circuit, infrared signal transceiver circuit includes infrared diode, with the IO interface that infrared diode electricity is connected and through the circuit function module that IO interface and infrared diode electricity are connected, infrared diode is used for receiving the infrared light and converts it into the electric current, or converts the electric current received into the infrared light and launches; the IO interface is a hardware interface of the integrated circuit chip; the circuit function module is an analog circuit in the integrated circuit chip and is used for receiving an internal emission control signal to realize an infrared emission function and converting a current signal output by the infrared diode into a voltage signal to amplify and identify the voltage signal to realize an infrared receiving function.

Preferably, the circuit function module comprises a transmitting circuit module and an infrared receiving circuit module, the transmitting circuit module comprises a switch tube, and the transmitting circuit module is used for receiving an internal transmitting control signal and controlling the switch tube to be switched on or switched off according to the transmitting control signal; the infrared receiving circuit module comprises a first resistor, an in-phase proportional operation module and an analog-to-digital conversion module; the first resistor is used for converting the current generated by the infrared diode into voltage; the in-phase proportion operation module is used for amplifying and outputting the electric signals at two ends of the first resistor; the analog-to-digital conversion module is used for converting the output signal of the in-phase proportion operation module into a digital signal and outputting the digital signal to the internal digital processing module;

the anode or the cathode of the infrared diode is connected to the IO interface; the IO interface is respectively connected to the output end of the transmitting circuit module, the first end of the first resistor and the first input end of the in-phase proportional operation module; the input end of the transmitting circuit module is used as the transmitting control signal input end of the infrared signal transceiving circuit; the second end of the first resistor is connected to the second input end of the in-phase proportion operation module and is used as a reference voltage input end of the infrared signal transceiving circuit; the output end of the in-phase proportion operation module is connected to the input end of the analog-to-digital conversion module; and the output end of the analog-to-digital conversion module is used as the output end of the receiving circuit of the infrared signal transceiving circuit.

Preferably, the infrared diode is a first infrared diode; the transmitting circuit module comprises a second resistor and an NMOS (N-channel metal oxide semiconductor) tube, and the NMOS tube is the switch tube; the in-phase proportional operation module comprises an operational amplifier, a third resistor and a fourth resistor; the anode of the first infrared diode is connected to a power supply voltage, and the cathode of the first infrared diode is connected to the IO interface; the IO interface is respectively connected to the first end of the second resistor, the first end of the first resistor and the positive input end of the operational amplifier; the drain electrode of the NMOS tube is connected to the second end of the second resistor, the source electrode of the NMOS tube is connected to the ground, and the grid electrode of the NMOS tube is used as the emission control signal input end of the infrared signal transceiving circuit; the second end of the first resistor is connected to the first end of the third resistor and is used as the reference voltage input end of the infrared signal transceiving circuit; the second end of the third resistor is respectively connected to the first end of the fourth resistor and the negative input end of the operational amplifier; and the output end of the operational amplifier is respectively connected to the second end of the fourth resistor and the input end of the analog-to-digital conversion module.

Preferably, the analog-to-digital conversion module is an analog-to-digital converter.

Preferably, the infrared diode is a second infrared diode; the transmitting circuit module comprises a fifth resistor and a PMOS (P-channel metal oxide semiconductor) tube, and the PMOS tube is the switch tube; the in-phase proportional operation module comprises an operational amplifier, a third resistor and a fourth resistor; the cathode of the second infrared diode is connected to the ground, and the anode of the second infrared diode is connected to the IO interface; the IO interface is respectively connected to the second end of the fifth resistor, the first end of the first resistor, and the positive input end of the operational amplifier; the drain electrode of the PMOS tube is connected to the first end of the fifth resistor, the source electrode of the PMOS tube is connected to power supply voltage, and the grid electrode of the PMOS tube is used as the emission control signal input end of the infrared signal transceiving circuit; the second end of the first resistor is connected to the first end of the third resistor and is used as the reference voltage input end of the infrared signal transceiving circuit; the second end of the third resistor is respectively connected to the first end of the fourth resistor and the negative input end of the operational amplifier; and the output end of the operational amplifier is respectively connected to the second end of the fourth resistor and the input end of the analog-to-digital conversion module.

Preferably, the analog-to-digital conversion module is an analog-to-digital converter.

The utility model also provides an integrated circuit chip, which is the integrated circuit chip, and the integrated circuit chip also comprises an emission control module and a digital processing module which are respectively and electrically connected with the circuit function module; the emission control module is used for generating the emission control signal; the digital processing module is used for receiving the digital signals generated by the circuit function module and carrying out operation processing on the digital signals.

The utility model also provides an infrared signal transceiver equipment, this equipment includes infrared signal transceiver circuit.

Compared with the prior art, the utility model discloses an infrared signal transceiver circuit, integrated circuit chip and infrared signal transceiver device's technical scheme adopts series connection's infrared diode, IO interface and circuit function module in proper order. Specifically, the infrared diode is electrically connected with the circuit function module through an IO interface, and the circuit function module is used for receiving an internal emission control signal to realize an infrared emission function, and converting a current signal output by the infrared diode into a voltage signal, and then amplifying and identifying the voltage signal to realize an infrared receiving function. The infrared diode is independent of the outside of the integrated circuit chip and is connected through an IO interface, so that the circuit is simple in structure, and the circuit function module is integrated in the integrated circuit chip, so that the integrated circuit chip is few in peripheral materials and easy to use; the circuit of the infrared signal receiving and transmitting circuit reduces the influence of parasitic capacitance existing in full integration, and the whole scheme adopting the circuit has high integration level, long learning distance and good learning effect.

Drawings

The present invention will be described in detail with reference to the accompanying drawings. The foregoing and other aspects of the invention will become more apparent and more readily appreciated from the following detailed description, taken in conjunction with the accompanying drawings. In the drawings:

fig. 1 is a circuit structure diagram of the infrared signal transceiver circuit of the present invention;

fig. 2 is a circuit structure diagram of an infrared signal transceiver circuit according to a first embodiment of the present invention;

fig. 3 is a voltage curve of the first resistor of the infrared signal transceiving circuit of the present invention under different infrared source intensities;

fig. 4 is a voltage curve of the inphase proportion operation module input signal and output signal of the infrared signal transceiving circuit of the present invention;

fig. 5 is a schematic diagram of the analog-to-digital conversion module of the infrared signal transceiving circuit of the present invention sampling an input signal;

fig. 6 is a circuit structure diagram of a second embodiment of the infrared signal transceiver circuit of the present invention.

Detailed Description

The following detailed description of the embodiments of the present invention will be made with reference to the accompanying drawings.

The embodiments/examples set forth herein are specific embodiments of the present invention and are presented for illustrative purposes only, and are not intended to be construed as limitations on the scope of the invention. In addition to the embodiments described herein, those skilled in the art will be able to employ other technical solutions which are obvious based on the disclosure of the claims and the specification of the present application, and these technical solutions include those which make any obvious replacement or modification of the embodiments described herein, and all of which are within the scope of the present invention.

Referring to fig. 1, the present invention provides an infrared signal transceiver circuit 100. The infrared signal receiving and transmitting circuit 100 comprises an infrared diode 1, an IO interface 5 electrically connected with the infrared diode 1 and a circuit function module 8 electrically connected with the infrared diode 1 through the IO interface 5.

The infrared diode 1 is used for receiving infrared light and converting it into current, or converting the received current into infrared light and emitting it.

The IO interface 5 is a hardware interface of the integrated circuit chip.

The circuit function module 8 is an analog circuit inside the integrated circuit chip. The circuit structure is simple due to the arrangement, and the circuit function module 8 is integrated in the integrated circuit chip, so that the peripheral materials of the whole scheme are less, and the use is easy. The circuit function module 8 is used for receiving an internal control signal to realize an infrared emission function, and is used for converting a current signal output by the infrared diode 1 into a voltage signal, amplifying and identifying the voltage signal to realize an infrared receiving function.

The infrared diode 1 is electrically connected to the circuit function module 8 through an IO interface 5 of the integrated circuit chip.

The infrared diode 1 is independent from the outside of the integrated circuit chip by the circuit structure, and only one infrared emitting diode is needed at the periphery of the scheme. Peripheral materials of the integrated circuit chip are saved to the greatest extent in the scheme, and meanwhile, the circuit function module 8 of the integrated circuit chip is electrically connected with the infrared diode 1 through only one IO interface 5. Thereby simplifying the circuit complexity of the PCB and reducing the scheme cost.

The circuit function module 8 comprises a transmitting circuit module 2 and an infrared receiving circuit module 6. The transmitting circuit module 2 and the infrared receiving circuit module 6 realize the switching of the infrared receiving and transmitting functions through the internal configuration of the integrated circuit chip.

The transmitting circuit module 2 comprises a switch tube. The transmitting circuit module 2 is used for receiving an internal transmitting control signal and controlling the switching tube to be switched on or switched off according to the transmitting control signal.

When the infrared signal transceiver circuit is set to an infrared transmitting state, the transmitting circuit module 2 controls the switching tube to be switched on and off; when the infrared signal transceiver circuit is set to an infrared receiving state, the transmitting circuit module 2 controls the switching tube to be cut off.

The infrared receiving circuit module 6 comprises a first resistor R1, an in-phase proportional operation module 3 and an analog-to-digital conversion module 4.

The first resistor R1 is used to convert the current generated by the infrared diode 1 into a voltage. The first resistor R1 is electrically connected to the anode or cathode of the infrared diode 1.

The in-phase proportion operation module 3 is configured to amplify and output an electrical signal at two ends of the first resistor R1. Two ends of the first resistor R1 are electrically connected to two input ends of the in-phase proportional operation module 3, respectively. The in-phase proportion operation module 3 amplifies weak electrical signals at two ends of the first resistor R1, so that the requirement of the circuit on infrared light intensity can be reduced, and the dependence of the infrared signal transceiver circuit 100 on infrared light source intensity is low.

The analog-to-digital conversion module 4 is configured to convert the output signal of the in-phase proportional operation module 3 into a digital signal and output the digital signal to an internal digital processing module.

The circuit structure of the infrared signal transceiving circuit 100 is as follows:

and the anode or the cathode of the infrared diode 1 is connected to the IO interface 5.

The IO interface 5 is respectively connected to the output end of the transmitting circuit module 2, the first end of the first resistor R1, and the first input end of the in-phase proportional operation module 3.

The input end of the transmitting circuit module 2 is used as the transmitting control signal input end TX of the infrared signal transceiving circuit 100.

A second end of the first resistor R1 is connected to a second input end of the in-phase proportional operation module 3, and is used as a reference voltage input end VREF of the infrared signal transceiving circuit 100.

The output end of the in-phase proportion operation module 3 is connected to the input end of the analog-to-digital conversion module 4.

The output end of the analog-to-digital conversion module 4 is used as the receiving circuit output end RX of the infrared signal transceiving circuit.

The transmitting circuit module 2, the first resistor R1, the in-phase proportional operation module 3, and the analog-to-digital conversion module 4 may all be integrated into a main control chip (the integrated circuit chip) of the remote controller. Therefore, the infrared diode 1 is used as a peripheral material of the main control chip, and only one IO interface 5 is reserved in the whole technical scheme, so that the remote control circuit is simple and low in cost. In addition, the infrared signal transceiver circuit 100 may be implemented by a standard CMOS process, but is not limited to the standard CMOS process, such as a BCD process. The infrared signal transceiving circuit 100 can reduce the influence of parasitic capacitance on the attenuation of the photocurrent to voltage conversion process, and improve the signal recognition rate when the infrared source is far away or the infrared source is weak in strength.

To illustrate the circuit principles and advantages of the infrared transceiver circuit 100 in detail, the following two embodiments are described in detail:

(embodiment one)

Referring to fig. 2, fig. 2 is a circuit structure diagram of an infrared signal transceiver circuit according to a first embodiment of the present invention. The first embodiment provides the infrared signal transceiving circuit 200.

The infrared signal transceiving circuit 200 includes an infrared diode 201, a transmitting circuit module 202, a first resistor R1, an in-phase proportional operation module 203, and an analog-to-digital conversion module 204.

In one embodiment of the present invention, the first,

the infrared diode 201 is a first infrared diode D1.

The transmitting circuit module 202 includes a second resistor R2 and an NMOS transistor M1. The NMOS tube M1 is the switch tube.

The in-phase proportional operation module 203 comprises an operational amplifier OP, a third resistor R3 and a fourth resistor R4.

In this embodiment, the analog-to-digital conversion module 204 is an analog-to-digital converter.

The circuit structure of the infrared signal transceiving circuit 200 is as follows:

the anode of the first infrared diode D1 is connected to a power supply voltage VDD, and the cathode of the first infrared diode D1 is connected to the IO interface 5.

The IO interface 5 is respectively connected to the first end of the second resistor R2, the first end of the first resistor, and the positive input end of the operational amplifier OP.

The drain of the NMOS transistor M1 is connected to the second terminal of the second resistor R2. The source of the NMOS transistor M1 is connected to ground GND. The gate of the NMOS transistor M1 is used as the transmission control signal input terminal TX of the infrared signal transceiver circuit 200.

The second end of the first resistor is connected to the first end of the third resistor R3, and serves as the reference voltage input end VREF of the infrared transceiver circuit 200.

A second end of the third resistor R3 is connected to a first end of the fourth resistor R4 and a negative input terminal of the operational amplifier OP, respectively.

The output end of the operational amplifier OP is respectively connected to the second end of the fourth resistor R4 and the input end of the analog-to-digital conversion module 204.

An output end of the analog-to-digital conversion module 204 is used as a receiving circuit output end RX of the infrared signal transceiving circuit 200.

The circuit principle of the infrared signal transceiving circuit 200 is as follows:

the transmitting circuit for infrared transmission of the infrared signal transceiving circuit 200 is composed of the first infrared diode D1, the NMOS transistor M1, and the second resistor R2.

Wherein,

the NMOS transistor M1 meets the current requirement when the first infrared diode D1 is conducted in the forward direction.

The second resistor R2 is a current limiting resistor, may be an actual resistor, or may be replaced by the on-resistance of the NMOS transistor M1. In the transmission mode of the infrared signal transceiver circuit 200, the in-phase proportional operation module 203 is turned off, and the circuit node of the reference voltage input terminal VREF presents a high impedance.

The reference voltage VREF1 needs to have a current driving capability, the first infrared diode D1 and the in-phase proportional operation module 203 need to draw current from the reference voltage input terminal VREF, and the implementation method can adopt strong driving voltages such as LDO output or BUF output.

The receiving circuit for infrared emission of the infrared signal transceiving circuit 200 is composed of an infrared diode 201, a first resistor R1, an in-phase proportional operation module 203, and an analog-to-digital conversion module 204.

The reference voltage VREF1 of the reference voltage input end VREF is lower than the power supply voltage VDD, the voltage difference between the reference voltage VREF1 and the power supply voltage VDD cannot exceed the same-direction conduction voltage drop of the infrared diode 201, and meanwhile the voltage detection output space of the same-phase proportion operation module 203 is required to meet the requirement when the same-phase proportion operation module amplifies an input signal. And at the same time, when the infrared diode 201 is used as an infrared receiving device, the working state of the infrared diode 201 is in a cut-off state.

In the infrared learning mode, the NMOS transistor M1 is in an off state. When no infrared light is irradiated, the reference voltage VREF1 pulls the VIO voltage to the voltage value of the reference voltage VREF1 through the first resistor R1, and the reference voltage VREF1 is used as the DC bias voltage of the in-phase proportional amplifier, at this time, both the positive and negative input voltages of the operational amplifier OP of the in-phase proportional operational module 203 are the voltage value of the reference voltage VREF1, the output voltage of the operational amplifier OP is also the voltage value of the reference voltage VREF1, and the analog-to-digital conversion module 204 converts the output voltage of the in-phase proportional operational module 203 into a digital signal.

The working process is described in detail in the following ideal case (without taking into account non-ideal factors):

when the infrared light irradiates, the cathode of the first infrared diode D1 generates a photocurrent, and the current flows from the inside of the first infrared diode D1 to the anode thereof. The reference voltage VREF1 supplements the same current, which flows through the first resistor R1 and then enters the cathode of the first infrared diode D1, so as to form a current loop. At this time, the voltage at the VIO node where the first resistor R1 and the first infrared diode D1 are connected drops, and the dropped voltage is captured by the in-phase proportional operation module 203.

The in-phase proportion operation module 203 has a fixed gain or an adjustable gain. Providing greater flexibility. If the gain of the in-phase proportional operation module 203 is a, the output end of the in-phase proportional operation module 203 will generate a voltage with a reduced amplitude of a times. Thus, the in-phase scaling module 203 provides signal amplification. The input of the in-phase proportional operation module 203 has a high impedance characteristic, so that the input has the same-direction amplification and no attenuation.

When the infrared light is not irradiated, the photocurrent disappears, and the cathode of the first infrared diode D1 is restored to the voltage value of the voltage reference voltage VREF1 by the reference voltage VREF1 and the first resistor R1. A trip signal is generated at the cathode of the first infrared diode D1. Meanwhile, a jump signal with the same direction and a multiple of input amplitude is generated at the output end of the in-phase proportion operation module 203. The analog-to-digital conversion module 204 converts the voltage output by the in-phase proportional operation module 203 into a digital signal, and the digital signal enters a logic circuit inside the main control chip for subsequent processing such as filtering and storage. The analog-to-digital conversion module 204 realizes sampling and identification of the output voltage of the in-phase proportion operation module 203, and the module does not need special design in a main control chip of the remote controller. The multi-bit analog-to-digital converter can enable the circuit to have longer identification distance and robustness than a single-bit analog-to-digital converter in design consideration. Therefore, the analog-to-digital conversion module 204 has a high degree of recognition of the attenuation of the preceding-stage parasitic capacitance.

It should be noted that the influence of the non-ideal factors on the infrared signal transceiver circuit 200 includes:

the photosensitive characteristic of the first infrared diode D1 is such that the stronger the illumination light, the greater the photocurrent generated, and the closer the infrared source, the greater the photocurrent. By using the first infrared diode D1 as a receiving tube, the photoelectric conversion sensitivity is not as strong as that of a special infrared receiving head, the generated photocurrent is weak, and the influence of parasitic capacitance and noise of other modules is easily caused.

Parasitic capacitance effects: the parasitic capacitor is in open circuit under direct current, and the impedance of the parasitic capacitor is infinite; when an alternating current signal is input, the impedance becomes smaller as the signal frequency becomes larger. The parasitic capacitance is not limited to the parasitic capacitance of the first infrared diode D1 itself, but also includes the parasitic capacitance of the NMOS transistor M1 itself. The infrared light to be processed by the infrared signal transceiver circuit 200 is a carrier signal of 32-56KHz, and the capacitor is no longer infinite impedance under an alternating current signal. During the time when the carrier wave infrared light is irradiated, the capacitor stored charge absorbs the photocurrent, and the voltage amplitude generated by the decrease of the photocurrent of the first resistor R1 decreases. When the infrared light stops irradiating, the capacitor supplements charges to ensure that the voltage of the VIO node cannot be recovered in time.

Referring to fig. 3, fig. 3 is a voltage curve of the first resistor of the infrared signal transceiver circuit according to the present invention under different infrared source intensities. In this case, the voltage amplitude generated at the first resistor R1 becomes smaller when the intensity of the light source is decreased or the distance of the light source is increased. The parasitic capacitance attenuates the magnitude of the voltage across the first resistor R1 and the rate of change of the voltage. W1 is the voltage curve of the first resistor R1 in an ideal case. W2 is the voltage curve of the first resistor R1 under non-ideal conditions.

The in-phase proportional operation module 203 has a high-impedance input characteristic, and does not attenuate photocurrent, the reference voltage VREF1 under internal low noise can isolate power noise interference to a certain extent, meanwhile, the reference voltage VREF1 is also a static operating point of the operational amplifier OP of the CMOS structure, and the conversion voltage of the third resistor R3 to the photocurrent can be responded to in time. The in-phase proportional operation module 203 can amplify the weak electrical signal on the first resistor R1, so as to reduce the requirement for infrared light intensity. It should be noted here that the in-phase proportional operation module 203 amplifies the input signal without difference, and the influence of the parasitic capacitance on the input signal is also amplified by the in-phase proportional operational amplifier.

Referring to fig. 4, fig. 4 is a voltage curve of the inphase proportional operation module input signal and output signal of the infrared signal transceiver circuit of the present invention. W3 is an input signal of the in-phase proportional operation module 203 under the influence of parasitic capacitance, wherein the internal low noise reference voltage VREF 1. W4 is the output signal of the in-phase scaling module 203, wherein the internal low noise reference voltage VREF2 is the amplified reference voltage of the internal low noise reference voltage VREF 1. The conventional comparator scheme in the related art cannot perform the identification of the above signal using a VREF voltage. Because the high and low voltages of the signal after the signal attenuated by the parasitic capacitance is subjected to the same-direction proportional amplification are not determined any more.

Referring to fig. 5, fig. 5 is a schematic diagram of the analog-to-digital conversion module 204 of the infrared signal transceiving circuit 200 according to the present invention sampling an input signal. W5 and W6 are schematic diagrams of the analog-to-digital conversion module 204 sampling the signals W1 and W2 in fig. 3, and the black dots D0 are sampling points of the analog-to-digital conversion circuit. The analog-to-digital conversion module 204 is adopted to receive the output of the in-phase proportion operation module 203, the analog-to-digital conversion module 204 has finer identification degree on the input signal, the characteristic of analog-to-digital conversion is not explained here, and the problem of uncertainty of the signal amplitude after being attenuated by the parasitic capacitance can be solved. The analog-to-digital conversion module 204 converts the output voltage of the in-phase proportion operation module 203 into a digital signal. The values collected by different light source intensities are different, the subsequent algorithm can process and distinguish the values, the in-phase proportional operation module 203 can obtain an initial voltage value in one learning, the lowest voltage value and the highest single voltage value in the conversion and some ascending and descending intermediate voltage values, data are transmitted to the subsequent algorithm circuit of the main control chip of the remote controller for processing, and the simplest processing is that the high and low voltages except the initial voltage in the learning are taken as the high and low levels of the carrier signal. Even if the original signal is attenuated by a large proportion by the capacitor, the original signal can still be identified by a subsequent circuit. The detailed algorithmic logic is not described in detail here.

In summary, the utility model discloses infrared signal transceiver circuit 200 utilizes first infrared diode D1 has designed infrared transmitting circuit and the infrared receiving circuit that can realize on standard CMOS technology the full integration as infrared receiving device. The utility model discloses infrared signal transceiver circuit 200 scheme periphery only needs one first infrared diode D1 can. Peripheral materials are saved to the maximum extent in the scheme, the complexity of a PCB circuit is simplified, and the scheme cost is reduced. In the learning effect, the defects of the existing scheme are optimized and improved by the receiving circuit, the dependence of the scheme on the intensity of the infrared light source is reduced, and the sensitivity and the reliability of the receiving circuit are improved.

(second embodiment)

The second embodiment is basically the same as the first embodiment in circuit structure, and the second embodiment replaces the NMOS transistor of the first embodiment with a PMOS transistor as a switching transistor, and replaces the infrared diode of the infrared emission emitting circuit from being connected to the power voltage to being grounded. While adjusting the voltage value of the reference voltage VREF1 to be slightly larger than the voltage value of the ground reference, it is also necessary to ensure that the voltage value of the reference voltage VREF1 is smaller than the forward conduction voltage of the infrared diode.

Referring to fig. 6, in particular, fig. 6 is a circuit structure diagram of a second embodiment of the infrared signal transceiver circuit of the present invention. The second embodiment provides an infrared signal transceiving circuit 300.

The infrared signal transceiver circuit 200 includes an infrared diode 201, a transmitting circuit module 302, a first resistor R1, an in-phase proportional operation module 303, and an analog-to-digital conversion module 304.

The difference between the second embodiment and the first embodiment is that:

the infrared diode 301 is a second infrared diode D2; the transmitting circuit module 302 includes a fifth resistor R5 and a PMOS transistor M2. The PMOS tube is the switch tube.

Wherein, the circuit connection relationship is different in that:

the cathode of the second infrared diode D2 is connected to ground, and the anode of the second infrared diode D2 is connected to the IO interface 5.

The IO interface 5 is respectively connected to the second end of the fifth resistor R5, the first end of the first resistor R1, and the positive input end of the operational amplifier OP;

the drain of the PMOS transistor is connected to the first end of the fifth resistor, the source of the PMOS transistor is connected to the power supply voltage VDD, and the gate of the PMOS transistor serves as the transmission control signal input terminal TX of the infrared signal transceiver circuit 300.

When the infrared signal transceiving circuit 300 works, when the second infrared diode D2 receives infrared light irradiation, the voltage of the anode of the second infrared diode D2 changes, and the generated induced voltage is greater than the reference voltage VREF 1.

The utility model also provides an integrated circuit chip (not shown). The chip is an integrated circuit chip as described above, and the integrated circuit chip further includes a transmission control module and a digital processing module which are electrically connected to the circuit function module 8, respectively.

The emission control module is used for generating the emission control signal.

The digital processing module is configured to receive the digital signal generated by the circuit function module 8, and perform operation processing on the digital signal.

The utility model also provides an infrared signal transceiver (not shown). The apparatus includes the infrared signal transceiving circuit 100. The infrared signal transceiver is a universal remote controller, an intelligent voice remote controller or a Bluetooth remote controller.

Compared with the prior art, the utility model discloses an infrared signal transceiver circuit, integrated circuit chip and infrared signal transceiver device's technical scheme adopts series connection's infrared diode, IO interface and circuit function module in proper order. Specifically, the infrared diode is electrically connected with the circuit function module through an IO interface, and the circuit function module is used for receiving an internal emission control signal to realize an infrared emission function, and converting a current signal output by the infrared diode into a voltage signal, and then amplifying and identifying the voltage signal to realize an infrared receiving function. The infrared diode is independent of the outside of the integrated circuit chip and is connected through an IO interface, so that the circuit is simple in structure, and the circuit function module is integrated in the integrated circuit chip, so that the integrated circuit chip is few in peripheral materials and easy to use; the circuit of the infrared signal receiving and transmitting circuit reduces the influence of parasitic capacitance existing in full integration, and the whole scheme adopting the circuit has high integration level, long learning distance and good learning effect.

It should be noted that the above-mentioned embodiments described with reference to the drawings are only intended to illustrate the present invention and not to limit the scope of the present invention, and those skilled in the art should understand that modifications or equivalent substitutions made on the present invention without departing from the spirit and scope of the present invention should be included in the scope of the present invention. Furthermore, unless the context indicates otherwise, words that appear in the singular include the plural and vice versa. Additionally, all or a portion of any embodiment may be utilized with all or a portion of any other embodiment, unless stated otherwise.

Claims (8)

1. An infrared signal transceiving circuit is characterized by comprising an infrared diode, an IO interface electrically connected with the infrared diode and a circuit function module electrically connected with the infrared diode through the IO interface, wherein the infrared diode is used for receiving infrared light and converting the infrared light into current or converting the received current into infrared light and transmitting the infrared light; the IO interface is a hardware interface of the integrated circuit chip; the circuit function module is an analog circuit in the integrated circuit chip and is used for receiving an internal emission control signal to realize an infrared emission function and converting a current signal output by the infrared diode into a voltage signal to amplify and identify the voltage signal to realize an infrared receiving function.

2. The infrared signal transceiving circuit of claim 1, wherein the circuit function module comprises a transmitting circuit module and an infrared receiving circuit module,

the transmitting circuit module comprises a switch tube and is used for receiving an internal transmitting control signal and controlling the switch tube to be switched on or switched off according to the transmitting control signal;

the infrared receiving circuit module comprises a first resistor, an in-phase proportional operation module and an analog-to-digital conversion module;

the first resistor is used for converting the current generated by the infrared diode into voltage;

the in-phase proportion operation module is used for amplifying and outputting the electric signals at two ends of the first resistor;

the analog-to-digital conversion module is used for converting the output signal of the in-phase proportion operation module into a digital signal and outputting the digital signal to the internal digital processing module;

wherein,

the anode or the cathode of the infrared diode is connected to the IO interface;

the IO interface is respectively connected to the output end of the transmitting circuit module, the first end of the first resistor and the first input end of the in-phase proportional operation module;

the input end of the transmitting circuit module is used as the transmitting control signal input end of the infrared signal transceiving circuit;

the second end of the first resistor is connected to the second input end of the in-phase proportion operation module and is used as a reference voltage input end of the infrared signal transceiving circuit;

the output end of the in-phase proportion operation module is connected to the input end of the analog-to-digital conversion module;

and the output end of the analog-to-digital conversion module is used as the output end of the receiving circuit of the infrared signal transceiving circuit.

3. The infrared signal transceiving circuit of claim 2, wherein the infrared diode is a first infrared diode; the transmitting circuit module comprises a second resistor and an NMOS (N-channel metal oxide semiconductor) tube, and the NMOS tube is the switch tube; the in-phase proportional operation module comprises an operational amplifier, a third resistor and a fourth resistor; wherein,

the anode of the first infrared diode is connected to a power supply voltage, and the cathode of the first infrared diode is connected to the IO interface;

the IO interface is respectively connected to the first end of the second resistor, the first end of the first resistor and the positive input end of the operational amplifier;

the drain electrode of the NMOS tube is connected to the second end of the second resistor, the source electrode of the NMOS tube is connected to the ground, and the grid electrode of the NMOS tube is used as the emission control signal input end of the infrared signal transceiving circuit;

the second end of the first resistor is connected to the first end of the third resistor and is used as the reference voltage input end of the infrared signal transceiving circuit;

the second end of the third resistor is respectively connected to the first end of the fourth resistor and the negative input end of the operational amplifier;

and the output end of the operational amplifier is respectively connected to the second end of the fourth resistor and the input end of the analog-to-digital conversion module.

4. The infrared signal transceiving circuit of claim 3, wherein the analog-to-digital conversion module is an analog-to-digital converter.

5. The infrared signal transceiving circuit of claim 2, wherein the infrared diode is a second infrared diode; the transmitting circuit module comprises a fifth resistor and a PMOS (P-channel metal oxide semiconductor) tube, and the PMOS tube is the switch tube; the in-phase proportional operation module comprises an operational amplifier, a third resistor and a fourth resistor; wherein,

the cathode of the second infrared diode is connected to the ground, and the anode of the second infrared diode is connected to the IO interface;

the IO interface is respectively connected to the second end of the fifth resistor, the first end of the first resistor, and the positive input end of the operational amplifier;

the drain electrode of the PMOS tube is connected to the first end of the fifth resistor, the source electrode of the PMOS tube is connected to power supply voltage, and the grid electrode of the PMOS tube is used as the emission control signal input end of the infrared signal transceiving circuit;

the second end of the first resistor is connected to the first end of the third resistor and is used as the reference voltage input end of the infrared signal transceiving circuit;

the second end of the third resistor is respectively connected to the first end of the fourth resistor and the negative input end of the operational amplifier;

and the output end of the operational amplifier is respectively connected to the second end of the fourth resistor and the input end of the analog-to-digital conversion module.

6. The infrared signal transceiving circuit of claim 5, wherein the analog-to-digital conversion module is an analog-to-digital converter.

7. An integrated circuit chip, characterized in that the chip is an integrated circuit chip as claimed in claims 1 to 6, said integrated circuit chip further comprising a transmission control module and a digital processing module electrically connected to said circuit function modules, respectively; the emission control module is used for generating the emission control signal; the digital processing module is used for receiving the digital signals generated by the circuit function module and carrying out operation processing on the digital signals.

8. An infrared signal transceiving apparatus, comprising the infrared signal transceiving circuit as claimed in claims 1 to 6.

Images