CN207200689U - A kind of digital intercom chip and digital intercom equipment - Google Patents
A kind of digital intercom chip and digital intercom equipment Download PDFInfo
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- CN207200689U CN207200689U CN201720608646.7U CN201720608646U CN207200689U CN 207200689 U CN207200689 U CN 207200689U CN 201720608646 U CN201720608646 U CN 201720608646U CN 207200689 U CN207200689 U CN 207200689U
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Abstract
The utility model provides a kind of integrated talkback chip and digital intercom equipment, and its main control unit, voice signal codec unit, sound output amplifier unit, microphone amplifying circuit unit, PMU, memory cell, radio frequency baseband unit, RF transceiver unit, safe digital card driver element and communication bus are integrated on one chip by system level chip technology；So one single chip can realizes digital communication functions and the expanded function of safe digital card, based on this, the circuit of very little is used using the equipment can of the chip, solves the problems, such as to be unfavorable for device miniaturization caused by the receiver circuit complexity of existing digital handset.
Description
Technical field
It the utility model is related to digital intercom field, more particularly to a kind of digital intercom chip and digital intercom equipment.
Background technology
ETSI in order to meet the low and middle-end of European Countries specialty and commercial user to mobile communication
Need, DMR digital mobile radio system standard ETSI TS 102 361 are proposed in April, 2005, DMR is adjusted using 4FSK
System, channel spacing 12.5kHz, transmission rate 9.6kbps, multi-access mode are double time slot tdmas, speech encoding rate 3.6kbps.,
DMR digital mobile radio systems are applied to the industries such as public utilities, school, hospital, hotel, animal husbandry.Existing DMR intercoms
The traditional superhet double conversion scheme of receiver generally use, due to containing bulky crystal filter in circuit
And ceramic filter, cause the circuit complexity cost of digital intercom equipment high, be unfavorable for device miniaturization.
Utility model content
The utility model provides a kind of digital intercom chip and digital intercom equipment, to solve existing digital handset
The problem of receiver circuit complexity.
The utility model provides a kind of integrated talkback chip, including：Main control unit, voice signal codec unit, sound
Frequency output power amplifier unit, microphone amplifying circuit unit, PMU, memory cell, radio frequency baseband unit,
RF transceiver unit, safe digital card driver element and the communication bus for connecting each unit；Sound output amplifier
Unit is used for exports audio signal；Microphone amplifying circuit unit is used to receive audio signal；Safe digital card driver element base
In bus marco rule, communicated with extraneous safe digital card；Main control unit is used to control each device in integrated talkback chip
Work；RF transceiver unit is used to baseband signal being adjusted to high frequency carrier or base band letter is demodulated from high frequency carrier
Number, radio frequency baseband unit is used for the debugging demodulation for carrying out baseband signal；PMU is used to external voltage being converted to it
His chip internal component required voltage；Main control unit, voice signal codec unit, sound output amplifier unit,
Microphone amplifying circuit unit, PMU, memory cell, radio frequency baseband unit, RF transceiver unit, safe number
Code card driver element and communication bus are integrated on one chip by system level chip technology.
Further, main control unit includes first microprocessor unit and the first digital signal processing unit, radio frequency baseband
Unit includes the second microprocessor unit and the second digital signal processing unit.
Further, first microprocessor unit and/or the second microprocessor unit are 32 reduced instruction microcontroller lists
Member；First digital signal processing unit and/or the second digital signal processing unit are 16 bit stream pipeline type Digital Signal Processing lists
Member.
Further, voice signal codec unit is 16 voice signal codec units.
Further, memory cell is including at least one in PSRAM memory cells and FLASH memory unit.
Further, integrated talkback chip also includes FM fm broadcast receiver units, FM fm broadcast receiver units
For receiving FM fm broadcast signals；FM fm broadcast receivers unit is integrated in pairs by system level chip technology
Say in chip.
Further, integrated talkback chip also includes bluetooth radio receiver/transmitter unit, and bluetooth radio receives hair
Penetrate machine unit and be used for bluetooth；Bluetooth radio receiver/transmitter unit is integrated in by system level chip technology
In integrated talkback chip.
Further, PMU is used to 3.2V-4.2V external voltage being converted to digital signal processing unit
And the 1.4V voltages that memory cell needs, and voice signal codec unit, sound output amplifier unit, Mike
The 2.4V voltages that wind amplifier circuit unit, microprocessor unit and radio frequency mobile radio receiver transmitter unit need.
Corresponding, the utility model provides a kind of digital intercom equipment, including safe digital card, and the utility model
The integrated talkback chip of offer, safe digital card electrically connect with integrated talkback chip secure digital card driver element.
Further, digital intercom equipment also includes power amplifier, power amplifier and penetrating in integrated talkback chip
Frequency transceiver unit connects, for carrying out power amplification to the output signal of RF transceiver unit.
The beneficial effects of the utility model：
The utility model provides a kind of new integrated talkback chip and digital intercom equipment, and it includes main control unit, words
Sound signal codec unit, sound output amplifier unit, microphone amplifying circuit unit, PMU, storage
Device unit, radio frequency baseband unit, RF transceiver unit, safe digital card driver element and connect each unit communication it is total
Line；Sound output amplifier unit is used for exports audio signal；Microphone amplifying circuit unit is used to receive audio signal；
Safe digital card driver element is based on bus marco rule, is communicated with extraneous safe digital card；Main control unit is used to control
The work of each device in integrated talkback chip；RF transceiver unit is used to baseband signal being adjusted to high frequency carrier or from height
Baseband signal is demodulated in frequency carrier wave, radio frequency baseband unit is used for the debugging demodulation for carrying out baseband signal；PMU is used
In external voltage is converted into other chip internal component required voltages；Main control unit, voice signal codec unit, audio
Output power amplifier unit, microphone amplifying circuit unit, PMU, memory cell, radio frequency baseband unit, penetrate
Frequency transceiver unit, safe digital card driver element and communication bus are integrated in a piece of by system level chip technology
On chip；So one single chip can realizes digital communication functions and the expanded function of safe digital card, based on this, uses
The equipment can of the chip uses the circuit of very little, solve existing digital handset receiver circuit it is complicated caused by not
The problem of beneficial to device miniaturization.
Brief description of the drawings
Fig. 1 is a kind of structural representation for the integrated talkback chip that the utility model first embodiment provides；
Fig. 2 is another structural representation for the integrated talkback chip that the utility model first embodiment provides；
Fig. 3 is the circuit connection diagram for the existing digital handset that the utility model second embodiment is related to；
Fig. 4 is the structural representation for the integrated talkback chip that the utility model second embodiment provides；
Fig. 5 is the circuit connection diagram for the integrated talkback chip that the utility model second embodiment provides.
Embodiment
The further annotation explanation of output is now done to the utility model by way of embodiment combination accompanying drawing.
First embodiment：
Fig. 1 is the structural representation for the digital intercom chip that the utility model first embodiment provides, as shown in Figure 1,
In the present embodiment, digital intercom chip provided by the utility model includes：Main control unit 11, voice signal codec unit 12,
Sound output amplifier unit 13, microphone amplifying circuit unit 14, radio frequency baseband unit 15, PMU 16,
Memory cell 17, RF transceiver unit 18, safe digital card driver element 19 and the unshowned connection each units of Fig. 1
Communication bus；RF transceiver unit 18 is used to baseband signal is adjusted into high frequency carrier or demodulates base from high frequency carrier
Band signal, radio frequency baseband unit 15 are used for the debugging demodulation for carrying out baseband signal；Sound output amplifier unit 13 is used for
Exports audio signal；Microphone amplifying circuit unit 14 is used to receive audio signal；Safe digital card driver element 19 is based on total
Line traffic control rule, is communicated with extraneous safe digital card；Main control unit 11 is used to control each device in integrated talkback chip
Work；PMU 16 is used to external voltage being converted to other chip internal component required voltages；Main control unit 11,
Voice signal codec unit 12, sound output amplifier unit 13, microphone amplifying circuit unit 14, radio frequency baseband list
Member 15, PMU 16, memory cell 17, RF transceiver unit 18, safe digital card driver element 19 and company
The communication bus for connecing each unit is integrated on one chip by system level chip technology.
As shown in Fig. 2 in certain embodiments, the main control unit 11 in above-described embodiment includes first microprocessor unit
111 and first digital signal processing unit 112, radio frequency baseband unit 15 include the second microprocessor unit 151 and the second numeral
Signal processing unit 152.
As shown in figure 3, in certain embodiments, the first microprocessor unit 111 and/or second in above-described embodiment is micro-
Processor unit 151 is 32 reduced instruction micro-control units.
As shown in figure 3, in certain embodiments, the first digital signal processing unit 112 in above-described embodiment and/or
Two digital signal processing unit 152 is 16 bit stream pipeline type digital signal processing units.
As shown in figure 3, in certain embodiments, the voice signal codec unit in above-described embodiment is believed for 16 speeches
Number codec unit.
As shown in Fig. 2 in certain embodiments, the memory cell 17 in above-described embodiment includes PSRAM memory lists
It is at least one in member 171 and FLASH memory unit 172.
In certain embodiments, the safe digital card driver element in above-described embodiment is SD (Secure Digital
Memory Card, safe digital card) 1.1 versions driver, so can compatible more multi version SD card.
As shown in figure 4, in certain embodiments, the integrated talkback chip in above-described embodiment also connects including FM frequency modulation broadcastings
Receipts machine unit, FM fm broadcast receivers unit are used to receive FM fm broadcast signals；FM fm broadcast receiver units pass through
System level chip technology is integrated in integrated talkback chip.
As shown in figure 4, in certain embodiments, the integrated talkback chip in above-described embodiment also connects including bluetooth radio
Receiver/transmitter unit, bluetooth radio receiver/transmitter unit are used for bluetooth；Bluetooth radio receiver/transmitter list
Member is integrated in integrated talkback chip by system level chip technology.
In certain embodiments, the PMU in above-described embodiment is used to turn 3.2V-4.2V external voltage
It is changed to the 1.4V voltages that digital signal processing unit and memory cell need, and voice signal codec unit, audio are defeated
Go out Power Amplifier Unit, microphone amplifying circuit unit, microprocessor unit and radio frequency mobile radio receiver emitter
The 2.4V voltages that unit needs.
Corresponding, the utility model provides a kind of digital intercom equipment, including safe digital card, and the utility model
The integrated talkback chip of offer, safe digital card electrically connect with integrated talkback chip secure digital card driver element.
In certain embodiments, the digital intercom equipment in above-described embodiment also includes power amplifier, power amplifier
It is connected with the RF transceiver unit in integrated talkback chip, is put for carrying out power to the output signal of RF transceiver unit
Greatly.
The utility model provides a kind of new integrated talkback chip and digital intercom equipment, and it includes main control unit, words
Sound signal codec unit, sound output amplifier unit, microphone amplifying circuit unit, PMU, storage
Device unit, radio frequency baseband unit, RF transceiver unit, safe digital card driver element and connect each unit communication it is total
Line；Sound output amplifier unit is used for exports audio signal；Microphone amplifying circuit unit is used to receive audio signal；
Safe digital card driver element is based on bus marco rule, is communicated with extraneous safe digital card；Main control unit is used to control
The work of each device in integrated talkback chip；RF transceiver unit is used to baseband signal being adjusted to high frequency carrier or from height
Baseband signal is demodulated in frequency carrier wave, radio frequency baseband unit is used for the debugging demodulation for carrying out baseband signal；PMU is used
In external voltage is converted into other chip internal component required voltages；Main control unit, voice signal codec unit, audio
Output power amplifier unit, microphone amplifying circuit unit, PMU, memory cell, radio frequency baseband unit, penetrate
Frequency transceiver unit, safe digital card driver element and communication bus are integrated in a piece of by system level chip technology
On chip；So one single chip can realizes digital communication functions and the expanded function of safe digital card, based on this, uses
The equipment can of the chip uses the circuit of very little, solve existing digital handset receiver circuit it is complicated caused by not
The problem of beneficial to device miniaturization.
Further annotation explanation is done to the utility model in conjunction with concrete application scene.
Second embodiment：
The circuit for the digital handset that the present embodiment is related to is as shown in figure 3, it includes：LNA low-noise amplifiers 31, mixing
Device 32, adjustable I/Q signal amplifier 33, ADC analog and digital signals converter 34, DSP 35 and DAC numerals
Analog signal converter 36.
At work, the rf frequency modulated signal that antenna receives is very faint, will be defeated by low-noise amplifier 31
Enter signal and be amplified to suitable amplitude to go frequency mixer 32 to be mixed with the local oscillator in chip, it is unwanted to filter out some
Noise signal produces base band I/Q signal, and the working frequency of local oscillator is related to the working frequency of setting contents of channel, Ke Yi
100MHz is set between 1000MHz.Signal is amplified to suitable amplitude through variable gain amplifier 33 and passes through a/d converter again
34 become data signal, wherein also synchronous comprising signal, the processing of 12.5KHz LPFs etc..Data are sent to DSP Processor 35
It is middle to carry out various data processings, such as：The error-detection error-correction of digital signal, the compression of voice signal and decompression are received, DMR intercoms are empty
Middle interface protocol etc., meet the requirement of the European standards of DMR digital mobile radio systems standard ETSI TS 102 361, can be simultaneous
Hold every other DMR intercoms, the communication apparatus such as base station and intermediate station, the data after DSP is handled reach DAC digital simulations letter
Number converter 36 is converted into analog signal output to loudspeaker；Similarly, the microphone signal of speech enters ADC analog and digital signals and turned
Parallel operation, data signal is converted into, brewed DMR hairs are synthesized through DSP and with local oscillator VCO modulation
Penetrate machine signal.
From the figure 3, it may be seen that circuit in existing digital handset it is complicated, it is necessary to set independent microprocessor unit MCU,
DSP etc., circuit realiration is complicated, and equipment cost is high.
For this problem, a kind of monolithic SOC DMR digital mobile radio systems are present embodiments provided, it is tied
As shown in figure 4, being integrated with the devices such as radio-frequency transmitter emitter, MCU, DSP, it is specifically included composition：Radio frequency baseband unit
401st, 16 voice signal codec units 402, FM fm broadcast receivers unit 403, bluetooth (Bluetooth) radio connect
Receiver/transmitter unit 404, sound output amplifier unit 405, microphone amplifying circuit unit 406, main control unit 407,
Power management (PMU) unit 408,16MB PSRAM memory cells 409,16MB FLASH memories unit 410 and radio frequency are received
Send out device unit 411；In actual applications, RF transceiver unit 411 realizes the circuit function of circuit in dotted line frame in Fig. 3.
Specifically, the internal circuit diagram for the integrated talkback chip that the present embodiment provides is as shown in figure 5, it includes：
2 CPU, are defined as XCPU and BCPU；
2 DSP, are defined as DSP1 and DSP2；
Radio frequency chip is defined as RF Transceiver；
Wherein, BCPU and DSP2 belongs to radio frequency baseband unit, and radio frequency baseband unit can realize the debugging solution of baseband signal
To adjust, the modulation and demodulation algorithm in communication system is more, such as：FSK,4FSK,GFSK,PFSK；Conventional algorithm is 4FSK；
RF Transceiver belong to RF transceiver, and baseband signal is modulated to high frequency by RF Transceiver and carried
Ripple, or high frequency carrier demodulate baseband signal by RF Transceiver；
XCPU and DSP1 belongs to main control unit, and main control unit can connect conventional peripheral hardware, such as：Keyboard, LCD display,
Microphone, loudspeaker, sensors etc., main control unit realize major function logic and basic service function；
Main control unit is connected with Base Band Unit with SYS APB buses.
Communication data interface includes RTC interface, TIMER interfaces, DA interfaces, A D interface, CAM interfaces, LCD interfaces, KPD and connect
Mouth, I2C interface, SPI interface, UART interface, USB2.0 interfaces, LED drive interface, PWM interfaces, SD/MMC interfaces, GPIO connect
At least one of mouth, I2S interfaces.
The data emission process that this chip is related to is：Initial data is passed to Base Band Unit, Base Band Unit by main control unit
Initial data is converted to 4FSK signals, 4FSK signals are modulated to high frequency carrier by RF Transceiver and launched.This
The DRP data reception process that chip is related to is：High-frequency signal demodulates 4FSK signals, Base Band Unit handle by RF Transceiver
4FSK signals revert to original data, then are transferred to main control unit.
In actual applications, the RF signal strength of RF Transceiver devices output is limited, to adapt to 1W, 2W, 4W,
5W communication systems meet spy, it is necessary to which the high-frequency signal of output is amplified to specified intensity range with PA (power amplifying device) devices
Determine the requirement of communication system.
The chip that the present embodiment provides can realize digital communication system, and the system has high reliability and the spy such as at a distance
Property, communication function covers wired and wireless telecommunication system.Workable communication scenes are such as：DMR,PDT,Tetra,Astro,
GoTa, iDEN, IoT etc..
The chip that the present embodiment provides can be communicated with the SD card in the external world, realize the Function Extension based on SD card, such as
Extension of memory space etc..
In summary, by implementation of the present utility model, following beneficial effect at least be present：
The utility model provides a kind of new integrated talkback chip and digital intercom equipment, and it includes main control unit, words
Sound signal codec unit, sound output amplifier unit, microphone amplifying circuit unit, PMU, storage
Device unit, radio frequency baseband unit, RF transceiver unit, safe digital card driver element and connect each unit communication it is total
Line；Sound output amplifier unit is used for exports audio signal；Microphone amplifying circuit unit is used to receive audio signal；
Safe digital card driver element is based on bus marco rule, is communicated with extraneous safe digital card；Main control unit is used to control
The work of each device in integrated talkback chip；RF transceiver unit is used to baseband signal being adjusted to high frequency carrier or from height
Baseband signal is demodulated in frequency carrier wave, radio frequency baseband unit is used for the debugging demodulation for carrying out baseband signal；PMU is used
In external voltage is converted into other chip internal component required voltages；Main control unit, voice signal codec unit, audio
Output power amplifier unit, microphone amplifying circuit unit, PMU, memory cell, radio frequency baseband unit, penetrate
Frequency transceiver unit, safe digital card driver element and communication bus are integrated in a piece of by system level chip technology
On chip；So one single chip can realizes digital communication functions and the expanded function of safe digital card, based on this, uses
The equipment can of the chip uses the circuit of very little, solve existing digital handset receiver circuit it is complicated caused by not
The problem of beneficial to device miniaturization.
It the above is only specific embodiment of the present utility model, any formal limit not done to the utility model
System, every any simple modification, equivalent variations, combination made according to the technical essence of the utility model to embodiment of above
Or modify, still fall within the protection domain of technical solutions of the utility model.
Claims (10)
- A kind of 1. integrated talkback chip, it is characterised in that including：Main control unit, voice signal codec unit, audio output work( Rate amplifier unit, microphone amplifying circuit unit, PMU, memory cell, radio frequency baseband unit, radio-frequency receiving-transmitting Device unit, safe digital card driver element and the communication bus for connecting each unit；The sound output amplifier unit For exports audio signal；The microphone amplifying circuit unit is used to receive audio signal；The safe digital card driving is single Member is communicated based on bus marco rule with extraneous safe digital card；The main control unit is used to control the integrated talkback The work of each device in chip；The RF transceiver unit is used to baseband signal being adjusted to high frequency carrier or carried from high frequency Baseband signal is demodulated in ripple, the radio frequency baseband unit is used for the debugging demodulation for carrying out baseband signal；The power management list Member is used to external voltage being converted to other chip internal component required voltages；The main control unit, voice signal encoding and decoding Unit, sound output amplifier unit, microphone amplifying circuit unit, PMU, memory cell, radio frequency base Tape cell, RF transceiver unit, safe digital card driver element and communication bus pass through system level chip technology collection Into on one chip.
- 2. integrated talkback chip as claimed in claim 1, it is characterised in that the main control unit includes first microprocessor list Member and the first digital signal processing unit, the radio frequency baseband unit are included at the second microprocessor unit and the second data signal Manage unit.
- 3. integrated talkback chip as claimed in claim 2, it is characterised in that the first microprocessor unit and/or described Second microprocessor unit is 32 reduced instruction micro-control units；First digital signal processing unit and/or the second number Word signal processing unit is 16 bit stream pipeline type digital signal processing units.
- 4. integrated talkback chip as claimed in claim 1, it is characterised in that the voice signal codec unit is 16 words Sound signal codec unit.
- 5. integrated talkback chip as claimed in claim 1, it is characterised in that the memory cell includes PSRAM memories It is at least one in unit and FLASH memory unit.
- 6. integrated talkback chip as claimed in claim 1, it is characterised in that it is wide that the integrated talkback chip also includes FM frequency modulation Receiver unit is broadcast, the FM fm broadcast receivers unit is used to receive FM fm broadcast signals；The FM frequency modulation broadcastings connect Receipts machine unit is integrated in the integrated talkback chip by system level chip technology.
- 7. integrated talkback chip as claimed in claim 1, it is characterised in that it is wireless that the integrated talkback chip also includes bluetooth Electric receiver/transmitter unit, the bluetooth radio receiver/transmitter unit are used for bluetooth；The bluetooth radio Receiver/transmitter unit is integrated in the integrated talkback chip by system level chip technology.
- 8. the integrated talkback chip as described in any one of claim 1 to 7, it is characterised in that the PMU is used for 3.2V-4.2V external voltage is converted to the 1.4V electricity of the digital signal processing unit and memory cell needs Pressure, and the voice signal codec unit, sound output amplifier unit, microphone amplifying circuit unit, Wei Chu Manage the 2.4V voltages that device unit and radio frequency mobile radio receiver transmitter unit need.
- A kind of 9. digital intercom equipment, it is characterised in that including：Safe digital card, and such as any one of claim 1 to 8 institute The integrated talkback chip stated, the safe digital card electrically connect with the integrated talkback chip secure digital card driver element.
- 10. digital intercom equipment as claimed in claim 9, it is characterised in that also including power amplifier, the power amplification Device is connected with the RF transceiver unit in the integrated talkback chip, for the output signal to the RF transceiver unit Carry out power amplification.
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| CN201720608646.7U CN207200689U (en) | 2017-05-26 | 2017-05-26 | A kind of digital intercom chip and digital intercom equipment |
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| CN201720608646.7U CN207200689U (en) | 2017-05-26 | 2017-05-26 | A kind of digital intercom chip and digital intercom equipment |
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| CN207200689U true CN207200689U (en) | 2018-04-06 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111147098A (en) * | 2018-10-16 | 2020-05-12 | 力同科技股份有限公司 | Integrated intercom system chip and intercom |
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2017
- 2017-05-26 CN CN201720608646.7U patent/CN207200689U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111147098A (en) * | 2018-10-16 | 2020-05-12 | 力同科技股份有限公司 | Integrated intercom system chip and intercom |
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