CN217087895U - Vehicle-mounted RF circuit - Google Patents

Abstract

The utility model discloses a vehicle-mounted RF circuit, comprising an FD6818 radio frequency chip, an AT32F415RCT type MCU and a peripheral circuit. The peripheral circuit comprises ten resistors, twenty-six capacitors, two inductors, a crystal oscillator chip and two signal terminals ;This circuit adopts FD6818 high-integrated chip transceiver, which integrates functions such as frequency synthesizer and voltage-controlled oscillator, which can directly convert audio signals into RF carrier signals, and can also output RF signals to the mixer to participate in mixing, through AT32F415RCT Model MCU to control FD6818, can get a wider VCO oscillation frequency, used to provide the transmission frequency required for frequency modulation of the vehicle signal transceiver system, and receive the local oscillator frequency signal.

Description

A car RF circuit

technical field

The utility model belongs to the technical field of vehicle signal receiving, in particular to a vehicle RF circuit.

Background technique

The radio frequency (Radio Frequency, RF for short) circuit is a key part in the vehicle signal receiving system, which has a great influence on the performance of the vehicle signal receiving. The existing vehicle-mounted radios require circuits such as voltage-controlled oscillators, phase-locked loops, and amplifiers to generate RF signals, with many components, high cost, and complex design.

SUMMARY OF THE INVENTION

The utility model proposes a vehicle-mounted RF circuit, which adopts FD6818 high-integrated chip transceiver, integrates functions such as a frequency synthesizer and a voltage-controlled oscillator, which can directly convert audio signals into RF carrier signals, and can also output RF signals. Participate in the mixing of the mixer, and control the FD6818 through the AT32F415RCT MCU, which can obtain a wider VCO oscillation frequency, which is used to provide the transmission frequency required for the frequency modulation of the vehicle signal transceiver system, and receive the local oscillator frequency signal.

The purpose of the present utility model can be achieved through the following technical solutions:

A vehicle-mounted RF circuit, the RF circuit includes an FD6818 radio frequency chip, and the FD6818 radio frequency chip includes thirty-two terminals, which are AVDD, SCL, SDA, NC, XI, XO, BUSM in ascending order of terminal numbers. , SCN, AFOUT, NC, MICP, MICN, AVDD, NC , RFIN, NC, NC, RFOUT, NC, NC, NC, BLAS, NC, NC, CPIO7, CPIO6, CPIO5, CPIO4, CPIO3, CPIO2, CPIO1, CPIO0 , also includes AT32F415RCT type MCU and peripheral circuit, the peripheral circuit includes ten resistors, twenty-six capacitors, two inductors, a crystal oscillator chip and two signal terminals, the resistors are R362, R363, R364, R365 , R366, R367, R368, R369, R370, R371, the capacitors are C365, C366, C370, C371, C372, C373, C374, C375, C376, C377, C378, C379, C380, C381, C382, C383, C384, C385, C386, C387, C388, C389, C390, C391, C392, C395, the inductance includes L119 and L120, the crystal oscillator chip includes four terminals, which are VC, GND in ascending order of terminal numbers. , XOUT, SC, the signal terminals include FD6818_AO, FD6818_MI, RF_IN and LO, the first order AVDD and the first order NC terminal are respectively connected with SC terminal, R362, R371, C365, C371, C373, C390, L133 , C388, C392, C387, C391, C395 one end and the second order AVDD terminal, the eighth order NC, the ninth order NC terminal are electrically connected, and the other end of the R362 is electrically connected to the VC terminal, R363 and C366 one end respectively , the other end of the R371 is electrically connected to the BUSM terminal, the other end of the L133 is electrically connected to one end of the C380 and the 3.3V power supply, and the SCL, SDA, SCN, CPIO7, CPIO6 are respectively connected to R365 and C381, R368 and C383, One end of R364 and C382, R367 and C385, R366 and C371 are electrically connected, and the other ends of the R365, R368, R364, R367 and R366 are respectively connected with the PB9, PB8, PB3/JTDO, PC0/ADC012-10, PC0 of the MCU respectively. /ADC012-11 terminal is electrically connected, the XI terminal is electrically connected to one end of C372 and C376 respectively, the other end of the C372 is electrically connected to the XOUT terminal, the XO terminal is electrically connected to C377, the AFOU The T terminal is electrically connected to one end of C375 and C378 respectively, the other end of C375 is electrically connected to one end of R370, the other end of R370 is electrically connected to one end of C370 and the signal terminal of FC6818_AO respectively, and the MICP terminal is electrically connected to one end of C374 and C379 respectively , the other end of the C374 is electrically connected to one end of the R369, the other end of the R369 is electrically connected to the FC6818_MI signal terminal, the MICN terminal is electrically connected to one end of the C384, the RFIN terminal is electrically connected to one end of the L119 and L120 respectively, the L120 The other end is electrically connected to one end of the C389, the other end of the C389 is electrically connected to the RF_IN signal end, the RFOUT terminal is electrically connected to one end of the C386, the other end of the C386 is electrically connected to the signal end LO, the R363, L119, C365, The other ends of C366, C370, C371, C373, C376, C377, C378, C379, C380, C381, C382, C383, C384, C385, C387, C388, C390, C391, C392, and C395 are all grounded.

Further, the R362 and R363 are 22K ohms, the R364, R365, R366, R367, R368 and R369 are 1K ohms, the R370 is 4K7 ohms, and the R371 is 47K ohms.

Further, the crystal oscillator chip is CR105.

Further, the C365, C385 and C386 are all 470P, C366 is 103P, C370 is 220P, C371, C372, C387 and C388 are all 10P, C375, C392 and C395 are all 104P, C374 is 475P, C389 and C391 are 102P, C384 is 10Uf/6V, C373, C376, C377, C378, C379, C380, C381, C382, C383 and C390 are all NC (not used).

Further, the L119 and L120 are both winding inductances, which are used for matching frequencies. Different receiving frequencies can use different inductances, wherein L119 is 1UH, L120 is 6.8UH, and L133 is a magnetic bead inductance. The model is PZ1608D101- 2R0TF.

The utility model has the following beneficial effects due to the adoption of the above scheme:

The utility model proposes a vehicle-mounted RF circuit, which adopts the FD-6818 high-integrated chip transceiver, and controls the FD6818 through an AT32F415RCT MCU, which can obtain a wide VCO oscillation frequency, which is used to provide the vehicle-mounted signal transceiver system. The RF circuit has a wide frequency range and good stability.

Description of drawings

Fig. 1 is the circuit diagram of the utility model;

Figure 2 shows the MCU wiring diagram.

Detailed ways

The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the implementations. example. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work, any modifications, equivalent replacements, improvements, etc., shall be included in the protection of the present invention. within the range.

A vehicle-mounted RF circuit, as shown in Figure 1, a vehicle-mounted RF circuit, the RF circuit includes an FD6818 radio frequency chip, and the FD6818 radio frequency chip includes thirty-two terminals, which are AVDD in ascending order of terminal numbers. , SCL, SDA, NC, XI, XO, BUSM, SCN, AFOUT, NC, MICP, MICN, AVDD, NC , RFIN, NC, NC, RFOUT, NC, NC, NC, BLAS, NC, NC, CPIO7, CPIO6 , CPIO5, CPIO4, CPIO3, CPIO2, CPIO1, CPIO0; as shown in Figure 2, it also includes AT32F415RCT MCU and peripheral circuits, the peripheral circuits include ten resistors, twenty-six capacitors, two inductors, and a crystal oscillator chip and two signal terminals, the resistors are R362, R363, R364, R365, R366, R367, R368, R369, R370, R371, and the capacitors are C365, C366, C370, C371, C372, C373, C374, C375, C376, C377, C378, C379, C380, C381, C382, C383, C384, C385, C386, C387, C388, C389, C390, C391, C392, C395, the inductance includes L119 and L120, the crystal oscillator chip It includes four terminals, which are VC, GND, XOUT, SC in ascending order of terminal numbers. The signal terminals include FD6818_AO, FD6818_MI, RF_IN and LO. The first order AVDD and the first order NC terminal Connect to SC terminal, R362, R371, C365, C371, C373, C390, L133, C388, C392, C387, C391, C395 and the second order AVDD terminal, eighth order NC, ninth order NC terminal respectively. connection, the other end of the R362 is electrically connected to the VC terminal, R363 and C366 respectively, the other end of the R371 is electrically connected to the BUSM terminal, the other end of the L133 is electrically connected to one end of the C380 and the 3.3V power supply, the SCL, SDA, SCN, CPIO7, CPIO6 are electrically connected to one end of R365 and C381, R368 and C383, R364 and C382, R367 and C385, R366 and C371 respectively, and the other end of said R365, R368, R364, R367 and R366 are respectively connected to the The PB9, PB8, PB3/JTDO, PC0/ADC012-10, PC0/ADC012-11 terminals of the MCU are electrically connected, the XI terminal is electrically connected to one end of C372 and C376, and the other end of the C372 is electrically connected to the XOUT terminal, The XO terminal is electrically connected to C377, the AFOUT terminal is electrically connected to one end of C375 and C378, the other end of C375 is electrically connected to one end of R370, and the other end of R370 is electrically connected to one end of C370 and the signal terminal of FC6818_AO, respectively. The MICP terminal is electrically connected to one end of C374 and C379, the other end of the C374 is electrically connected to one end of R369, the other end of the R369 is electrically connected to the FC6818_MI signal terminal, the MICN terminal is electrically connected to one end of C384, and the RFIN terminals are respectively It is electrically connected to one end of L119 and L120, the other end of L120 is electrically connected to one end of C389, the other end of C389 is electrically connected to the RF_IN signal terminal, the RFOUT terminal is electrically connected to one end of C386, and the other end of C386 is electrically connected to the signal terminal LO Electrical connection, the R363, L119, C365, C366, C370, C371, C373, C376, C377, C378, C379, C380, C381, C382, C383, C384, C385, C387, C388, C390, C391, C392, C395 The other ends are grounded.

The R362 and R363 are both 22K ohms, the R364, R365, R366, R367, R368 and R369 are 1K ohms, the R370 is 4K7 ohms, and the R371 is 47K ohms.

The crystal oscillator chip is CR105.

C365, C385 and C386 are all 470P, C366 is 103P, C370 is 220P, C371, C372, C387 and C388 are all 10P, C375, C392 and C395 are all 104P, C374 is 475P, C389 and C391 are 102P, C384 10Uf/6V, C373, C376, C377, C378, C379, C380, C381, C382, C383 and C390 are all NC (not used).

The L119 and L120 are both winding inductances, which are used to match frequencies. Different receiving frequencies can use different inductances. Among them, L119 is 1UH, L120 is 6.8UH, and L133 is a magnetic bead inductance. The model is PZ1608D101-2R0TF.

Claims (5)

1. An on-vehicle RF circuit, the RF circuit includes FD6818 radio frequency chip, the FD6818 radio frequency chip includes thirty-two terminals, AVDD, SCL, SDA, NC, XI, XO, BUSM, SCN, AFOUT, NC, MICP, MICN, AVDD, NC, RFIN, NC, RFOUT, NC, BLAS, NC, CPIO7, CPIO6, CPIO5, CPIO4, CPIO3, CPIO2, CPIO1, CPIO0 according to terminal number in turn from small to large, characterized in that, the on-vehicle RF circuit also includes AT32F415RCT type MCU and peripheral circuit, the peripheral circuit includes ten resistors, twenty-six capacitors, two inductors, a crystal oscillator chip and two signal terminals, the resistors are R362, R363, R367, R364, R365, R366, R385, R368, R371, R376, R365, R375, C382, C380C, C382C, C380C, C383C, C382C, C383C, C383C, C371, C383, C371, NC, C371, NC, CPIO 371, NC, CPIO, NC, c392 and C395, the inductor comprises L119 and L120, the crystal oscillator chip comprises four terminals, the numbers of the terminals are respectively VC, GND, XOUT and SC IN sequence from small to large, the signal terminal comprises FD6818_ AO, FD6818_ MI, RF _ IN and LO, the first cis-position AVDD and first cis-position NC terminals are respectively and electrically connected with an SC terminal, R362, R371, C365, C371, C373, C390, L133, C388, C392, C387, C391 and C395 end, a second cis-position AVDD terminal, an eighth cis-position NC and a ninth cis-position NC terminal, the other end of the R362 is respectively and electrically connected with a VC terminal, one ends of R363 and C366, the other end of the R371 is electrically connected with an M terminal, the other end of the L133 is respectively and electrically connected with a C380 end and a 3.3V power supply, the SDA, CPI, PB, SCN, O7 and PB 6 are respectively and C366, the other ends of R366, R368, C368, SCIR 383, R382 and R383 are respectively and R9, the other ends of the SCIR 366, C366, SCIR 367 and PB 14, C366, C368, SCL 364 and R383 are respectively and R382, R383 are respectively and R9 IN sequence, PB8, PB3/JTDO, PC0/ADC012-10, PC0/ADC012-11 terminals, the XI terminal is electrically connected with C372 and C376 ends respectively, the other end of C372 is electrically connected with XOUT terminal, the XO terminal is electrically connected with C377, the AFOUT terminal is electrically connected with C375 and C378 ends respectively, the other end of C375 is electrically connected with R370 end, the other end of R370 is electrically connected with C370 end and FC6818_ AO signal end respectively, the MICP terminal is electrically connected with C374 and C379 ends respectively, the other end of C369 is electrically connected with R369 end, the other end of R369 is electrically connected with FC6818_ MI signal end, the MICN terminal is electrically connected with C384 end, the RFIN terminal is electrically connected with L119 and L120 end respectively, the other end of L120 is electrically connected with C389 end, the other end of C389 is electrically connected with RF _ IN signal end, the RFOUT terminal is electrically connected with C386 end, the other end of C LO end is electrically connected with signal end, The other ends of the R363, the L119, the C365, the C366, the C370, the C371, the C373, the C376, the C377, the C378, the C379, the C380, the C381, the C382, the C383, the C384, the C385, the C387, the C388, the C390, the C391, the C392 and the C395 are all grounded.

2. The on-board RF circuit of claim 1, wherein R362 and R363 are each 22K, R364, R365, R366, R367, R368, and R369 are each 1K, R370 is 4K7 ohms, and R371 is 47K.

3. The on-board RF circuit of claim 1, wherein the crystal oscillator chip is CR 105.

4. The in-vehicle RF circuit of claim 1, wherein C365, C385 and C386 are all 470P, C366 is 103P, C370 is 220P, C371, C372, C387 and C388 are all 10P, C375, C392 and C395 are all 104P, C374 is 475P, C389 and C391 are 102P, C384 is 10Uf/6V, and C373, C376, C377, C378, C379, C380, C381, C382, C383 and C390 are all NC.

5. The on-board RF circuit of claim 1, wherein each of L119 and L120 is a wire-wound inductor for matching frequencies, different receiving frequencies can use different inductances, and L133 is a bead inductor of model PZ1608D101-2R0 TF.

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