There are A, B, C, D four operation buttons and an emission indicator on the remote control panel. The internal transmitter uses imported SAW resonators to stabilize the frequency, the frequency consistency is very good, the stability is extremely high, the frequency stability of the operating frequency is 315MHz is better than 10−5, and there is no need to adjust the frequency point during use. It is especially suitable for radio remote control such as multiple transmitters and receivers. The system is used, but currently the radio remote control module on the market generally still uses an LC oscillator, which has poor stability and consistency. Even if a high-quality fine-tuning capacitor is used, it is difficult to guarantee that the frequency that has been debugged will not occur when the temperature changes and the vibration. Offset, resulting in shortened launch distance.
The receiving module adopts the SMD chip manufacturing process to produce super-regenerate receiving mode. It contains a magnification shaping and decoding circuit and is extremely convenient to use.
1. There is a frequency selective circuit at the input end of the antenna, instead of relying on the frequency selection effect of the 1/4 wavelength antenna. When the control distance is short, it can be cut short or even remove the external antenna 2. The radiation of the receiving circuit itself is extremely small, plus the back side of the circuit module The shielding effect of the grounded copper foil can reduce the leakage of self-oscillation and the intrusion of external interference signals.
3. The receiver uses a high-precision copper core inductor with a skeleton to adjust the frequency to 315M after sealing. Compared with the circuit using adjustable capacitance to adjust the receiving frequency, the temperature, humidity stability, and mechanical vibration resistance are all greatly increased. improve. Adjustable capacitance adjustment accuracy is low, only 3/4 turn adjustment range, and adjustable inductance can be adjusted in multiple turns. After the adjustment of the adjustable capacitance, it cannot be sealed because the proximity or intrusion of various media, regardless of the conductor or the insulator, will cause the capacity of the capacitor to change, which will affect the receiving frequency. In addition, the unadjusted tunable capacitor is displaced between the stator and the rotor when it is subjected to vibration; when the temperature changes, thermal expansion and contraction will change the distance between the stator and the rotor; humidity changes due to changes in the medium to change capacity; Working in a humid environment also changes the capacity due to the oxidation of the stator and the rotor, which will seriously affect the stability of the receiving frequency, and the use of an adjustable inductor can solve these problems because the inductor can be sealed after adjustment. Insulator mounting agent does not change the inductance, and due to the chip technology, even if the vibration is strong, there is no need to worry about the drift of the receiver frequency. The receiving bandwidth of the receiving circuit is about 500KHz, and the center frequency of the product has been adjusted to 315MHz. The trimming inductor on the receiving chip has an adjustable range of about 5 MHz, and should not be easily changed during use to avoid affecting performance.
The receiving module has seven terminals, namely VCC, GND, D1, D2, D3, D4 and VT, where VCC is a 5V power supply terminal, GND is a ground terminal, VT terminal is a decoding effective output terminal, and D1 to D4 are four positions. The data latch output terminal can output a high level of about 4V, and the driving current is 2mA, corresponding to the vertical keys A, B, C, and D on the transmitter.
Principle of operation:
The PT2262 and PT2272 are a pair of COMS-specific coding circuits produced by the Pucheng Company in Taiwan. The oscillation frequency is adjusted by an external resistor. The coded signal generated by the PT2262 is composed of an address code, a data code, and a synchronization code to form a complete code word. After the decoder chip PT2272 receives the signal, the VT pin outputs a high level after its address code is compared twice, and at the same time, the corresponding data pin also outputs a high level. If the sending end keeps pressing the key, the encoding chip also Will launch continuously. When the transmitter does not press the button, the PT2262 does not turn on the power, and its 17-pin is low, so the 315MHz high-frequency transmission circuit does not work. When a button is pressed, the PT2262 is powered and its 17th pin is output. The modulated serial data signal, when the 17-pin is high during the high-frequency transmitter circuit 315MHz start-up and emit high-frequency signals, when the 17-pin low-level period of 315MHz high-frequency emission circuit to stop the oscillation, so high The frequency transmitting circuit is completely controlled by the digital signal output from the 17th pin of the PT2262, so that the amplitude keying (ASK modulation) is performed on the high frequency circuit and the amplitude modulation with a modulation degree of 100% is achieved.
PT2262 and PT2272 coded circuit 1 to 8 feet for the address setting pin, you can choose to hang empty, then connected to the power supply, grounding three states, 3 of the 8th power is 6561, so the address coding is not repeated 6561 group, only PT2262 The address code of PT2272 is the same as that of PT2272. In order to facilitate management, the eight-bit address encoding terminal of PT2262 and PT2272 are all left unconnected. If the user wants to change the address code, only the 1 to 8 pins of PT2262 and PT2272 are required. Set the same can be, for example, the first pin of the transmitter's PT2262 is connected to the positive power supply pin 5, the other pin is floating, then the receiver's PT2272 as long as the first pin is connected to pin 5 is connected to the positive supply, the other pin is floating Pairing reception can be achieved. When both address codes are exactly the same, the corresponding D1 to D4 terminals of the receiver output an interlocking high-level control signal of about 4V, and the VT terminal also outputs a decoded effective high-level signal. The user can increase these signals by one step and can drive relays, power transistors, etc. to perform remote control of the load switch.
PT2262/PT2272 chip usage information to change the remote address encoding method:
The remote controller's encoding and decoding chip provided here is PT2262 and PT2272 (or both SC2262 and SC2272 are fully compatible). Its 1 to 8 pins are address setting pins. Manufacturers are set at the factory to facilitate production management. If you want to use multiple remote controllers in practical use, do not want to interfere with each other, you must set different address codes for different sets of remote controllers. The address pins of the encoding and decoding chips can be selected: three states: floating, grounding, and connecting to the positive power supply. Therefore, the probability of the maximum non-repetition is 3, and the power of 8 is 6561. Therefore, the address coding repetition degree is 6561, as long as the PT2262 is The status of 1 to 8 pins of the PT2272 can be set to the same status to achieve remote control. The remote controllers with different address codes do not interfere with each other. For example, the first pin of the PT2262 of one of the transmitters is grounded, the fifth pin is connected to the positive power supply, and the other pin is floating. Then, the PT2272 of the receiver is also connected to the positive power supply as the first pin is connected to the fifth pin and the other pins are left unconnected. Pairing reception can be achieved.
Application Example 1. Method of making a single-channel latch type remote control switch Use: To open and close an alarm circuit remotely, or to turn the light on and off of a lamp: Press the A button of the remote controller, the alarm circuit The power is on or one lamp is on. After the button is released, it is still on or on. When only one of the buttons B, C, and D on the remote controller is pressed, the power of the alarm circuit is turned off or one of the lamp points is off, the release of the release button is still turned off, or the receiver of the remote circuit consumes power when it is on standby. Only 4 mA, very low power, suitable for some battery-powered or circuit-intensive applications.
2. To make a non-latching type of four-channel remote control switch:
Uses: Used for remote control of some occasions that need jog remote control, can realize up to four ways, such as remote control electric door opening and closing, some with touch switch control of the occasion, such as home appliances on the volume increase, decrease buttons, channels Increase and decrease the button.
The receiving module adopts the SMD chip manufacturing process to produce super-regenerate receiving mode. It contains a magnification shaping and decoding circuit and is extremely convenient to use.
1. There is a frequency selective circuit at the input end of the antenna, instead of relying on the frequency selection effect of the 1/4 wavelength antenna. When the control distance is short, it can be cut short or even remove the external antenna 2. The radiation of the receiving circuit itself is extremely small, plus the back side of the circuit module The shielding effect of the grounded copper foil can reduce the leakage of self-oscillation and the intrusion of external interference signals.
3. The receiver uses a high-precision copper core inductor with a skeleton to adjust the frequency to 315M after sealing. Compared with the circuit using adjustable capacitance to adjust the receiving frequency, the temperature, humidity stability, and mechanical vibration resistance are all greatly increased. improve. Adjustable capacitance adjustment accuracy is low, only 3/4 turn adjustment range, and adjustable inductance can be adjusted in multiple turns. After the adjustment of the adjustable capacitance, it cannot be sealed because the proximity or intrusion of various media, regardless of the conductor or the insulator, will cause the capacity of the capacitor to change, which will affect the receiving frequency. In addition, the unadjusted tunable capacitor is displaced between the stator and the rotor when it is subjected to vibration; when the temperature changes, thermal expansion and contraction will change the distance between the stator and the rotor; humidity changes due to changes in the medium to change capacity; Working in a humid environment also changes the capacity due to the oxidation of the stator and the rotor, which will seriously affect the stability of the receiving frequency, and the use of an adjustable inductor can solve these problems because the inductor can be sealed after adjustment. Insulator mounting agent does not change the inductance, and due to the chip technology, even if the vibration is strong, there is no need to worry about the drift of the receiver frequency. The receiving bandwidth of the receiving circuit is about 500KHz, and the center frequency of the product has been adjusted to 315MHz. The trimming inductor on the receiving chip has an adjustable range of about 5 MHz, and should not be easily changed during use to avoid affecting performance.
The receiving module has seven terminals, namely VCC, GND, D1, D2, D3, D4 and VT, where VCC is a 5V power supply terminal, GND is a ground terminal, VT terminal is a decoding effective output terminal, and D1 to D4 are four positions. The data latch output terminal can output a high level of about 4V, and the driving current is 2mA, corresponding to the vertical keys A, B, C, and D on the transmitter.
Principle of operation:
The PT2262 and PT2272 are a pair of COMS-specific coding circuits produced by the Pucheng Company in Taiwan. The oscillation frequency is adjusted by an external resistor. The coded signal generated by the PT2262 is composed of an address code, a data code, and a synchronization code to form a complete code word. After the decoder chip PT2272 receives the signal, the VT pin outputs a high level after its address code is compared twice, and at the same time, the corresponding data pin also outputs a high level. If the sending end keeps pressing the key, the encoding chip also Will launch continuously. When the transmitter does not press the button, the PT2262 does not turn on the power, and its 17-pin is low, so the 315MHz high-frequency transmission circuit does not work. When a button is pressed, the PT2262 is powered and its 17th pin is output. The modulated serial data signal, when the 17-pin is high during the high-frequency transmitter circuit 315MHz start-up and emit high-frequency signals, when the 17-pin low-level period of 315MHz high-frequency emission circuit to stop the oscillation, so high The frequency transmitting circuit is completely controlled by the digital signal output from the 17th pin of the PT2262, so that the amplitude keying (ASK modulation) is performed on the high frequency circuit and the amplitude modulation with a modulation degree of 100% is achieved.
PT2262 and PT2272 coded circuit 1 to 8 feet for the address setting pin, you can choose to hang empty, then connected to the power supply, grounding three states, 3 of the 8th power is 6561, so the address coding is not repeated 6561 group, only PT2262 The address code of PT2272 is the same as that of PT2272. In order to facilitate management, the eight-bit address encoding terminal of PT2262 and PT2272 are all left unconnected. If the user wants to change the address code, only the 1 to 8 pins of PT2262 and PT2272 are required. Set the same can be, for example, the first pin of the transmitter's PT2262 is connected to the positive power supply pin 5, the other pin is floating, then the receiver's PT2272 as long as the first pin is connected to pin 5 is connected to the positive supply, the other pin is floating Pairing reception can be achieved. When both address codes are exactly the same, the corresponding D1 to D4 terminals of the receiver output an interlocking high-level control signal of about 4V, and the VT terminal also outputs a decoded effective high-level signal. The user can increase these signals by one step and can drive relays, power transistors, etc. to perform remote control of the load switch.
PT2262/PT2272 chip usage information to change the remote address encoding method:
The remote controller's encoding and decoding chip provided here is PT2262 and PT2272 (or both SC2262 and SC2272 are fully compatible). Its 1 to 8 pins are address setting pins. Manufacturers are set at the factory to facilitate production management. If you want to use multiple remote controllers in practical use, do not want to interfere with each other, you must set different address codes for different sets of remote controllers. The address pins of the encoding and decoding chips can be selected: three states: floating, grounding, and connecting to the positive power supply. Therefore, the probability of the maximum non-repetition is 3, and the power of 8 is 6561. Therefore, the address coding repetition degree is 6561, as long as the PT2262 is The status of 1 to 8 pins of the PT2272 can be set to the same status to achieve remote control. The remote controllers with different address codes do not interfere with each other. For example, the first pin of the PT2262 of one of the transmitters is grounded, the fifth pin is connected to the positive power supply, and the other pin is floating. Then, the PT2272 of the receiver is also connected to the positive power supply as the first pin is connected to the fifth pin and the other pins are left unconnected. Pairing reception can be achieved.
Application Example 1. Method of making a single-channel latch type remote control switch Use: To open and close an alarm circuit remotely, or to turn the light on and off of a lamp: Press the A button of the remote controller, the alarm circuit The power is on or one lamp is on. After the button is released, it is still on or on. When only one of the buttons B, C, and D on the remote controller is pressed, the power of the alarm circuit is turned off or one of the lamp points is off, the release of the release button is still turned off, or the receiver of the remote circuit consumes power when it is on standby. Only 4 mA, very low power, suitable for some battery-powered or circuit-intensive applications.
2. To make a non-latching type of four-channel remote control switch:
Uses: Used for remote control of some occasions that need jog remote control, can realize up to four ways, such as remote control electric door opening and closing, some with touch switch control of the occasion, such as home appliances on the volume increase, decrease buttons, channels Increase and decrease the button.