Voice chip wt2003h4 B008 single chip to realize the quick design of intelligent doorbell scheme

With the continuous progress of intelligent wireless technology , Wireless doorbell has also entered thousands of households , The sales volume of doorbell products is also rising with people's demand , The technical quality of various doorbells on the market is also uneven . Weichuang bosom friend deeply summarizes and analyzes the problems existing in the market doorbell and carries out technical update iteration , Launched a powerful 、 Peripheral simple WT2003H4 B008 Special chip for doorbell , It meets the needs of product design engineers in doorbell industry for fast and simple design . This scheme is free of adjustment 433MHZ RF The receiving module cooperates WT2003H4 B008 A new generation of dedicated doorbell chip .

Let's first briefly understand the working principle of the doorbell ： When you ring the doorbell RF wireless 433MHZ High frequency carrier modulation digital encryption transmission , Re menstruation WT2003H4 B008 built-in DSP Processing decoding , Output built-in high-quality voice ringtones , There are PLL Automatic frequency locking , Avoid frequency deviation , It can make more stable transmission at different temperatures and environments , More penetrating to the wall , Make the product more stable and reliable in different seasons ,（ Most of the doorbell products on the market have some problems ： How complex the circuit components are 、 Small memory, poor sound quality 、 Frequency instability 、 The frequency on the market is 90MHZ-433MHZ, Most require manual debugging , The frequency is unstable after repeated debugging , Sensitive to temperature changes , Poor ability to penetrate the wall , The wall and door body are easy to have a great impact on the frequency in the machine , Cause insensitivity or failure after installation , Phenomena such as shortening sensing distance ）.

Weichuang bosom friend launched WT2003H4 B008 Doorbell chip scheme , From the beginning of chip design, it has improved many bad problems of doorbell products on the market , Powerful and simple circuit , The main features are ：

1. The chip has DSP Digital processing system ,ADC、DAC、 Decoding and other functions , Technical difficulties 、 The key points are integrated into the chip ;
2. built-in Flash The voice of multiple doorbells can be defined by the customer , Built in 100 second ~350 Second voice capacity ;
3. Support Power off memory function ;
4. built-in 0.5W Power amplifier output , Low distortion 、 Frequency response width 、 High quality low frequency channel with high signal-to-noise ratio , It can play and restore a high-quality sound source , Make the music beautiful ;
5. The encrypted signal transmitted wirelessly is decoded 、EV1527 Protocol and learning functions , Remote control and host , One on one remote control , You can also drag two remote controls , It will not interfere with products outside the setting ;

WT2003H Doorbell chip scheme , Reduce peripheral components , Production and installation are more convenient , At the same time, the debugging time is eliminated , It also greatly shortens the product development cycle , Products can be mass produced and put on the market quickly , Make the overall cost lower , Increase the competitiveness of products , Give users a better experience .

Application scenarios ：

1. The family opens the door 、 yard 、 community call ;
2. Hospital bed wireless voice call system ;
3. Table wireless voice call system ;
4. Building elevator wireless voice station reporting ;
5. Other specific call systems .

The function code of this scheme is ：B008, If you are interested in this case , You can use the function code in Weichuang bosom friend Find the corresponding product information on the website , You can also contact Weichuang bosom friend for relevant information .

Let's take an application example ：WT2003H4 B008 The design scheme of intelligent doorbell is presented intuitively ：（ It can be customized or IC Chip supply , Convenient for customers to choose ）

1. Smart doorbell Program Overview

SOP16  Package pin description  

 

2. Device selection

Position	model	Feature Overview
master control	WT2003H4	32 position DSP、 The highest frequency 120MHZ,Flash Rewritable 、…

 

a. Schematic design

3. Launch module （ Doorbell remote control )

4. Doorbell receiving module  

The key functions are as follows ：

IO Definition of mouth	S1	S2	D1、led
Function definition	Short press ： Volume plus （ It can be 32 level ） Great circulation , Play the current track at the same time	Short press ： Next song （ Great circulation ） Long press 3 second ：433 Pair learning （ When learning mode LED Flash , Determine success LED Long light for one second ,5 Seconds automatically exit the learning mode ）	Three flashing modes , When playing music , Slow flash . Flash ：6HZ Slow flash ：3HZ Changliang ：
	S1/S2 Press at the same time 3 second , Delete all learned codes , Delete successful LED Long light for one second

 5. Application framework diagram

6）WT2003H4 Basic functions and features

1.32 position DSP Voice chip 、32Mhz Internal oscillation ;

2. Working voltage 2.0~5.5V; Recommended voltage ：2.2~4.0V（ Due to the use of serial port TTL Level communication ）

3. Standby current 3MA, The resting quiescent current is less than 10UA

4、32bit Of PWM Output , Can drive directly 8R 0.5W horn ;

5. Support playing high-quality audio format ,（8kbps~320kbps） Beautiful voice MP3、WAV file ,

6. Customers can download the test board to replace the internal voice content of the chip online ;

7. Chip built in Flash Maximum 300 Second voice capacity , It has power down memory function .

8. The chip master program and the built-in stored data can be erased and then burned .

9. Low voltage detection function , It can be set when the voltage is lower than a certain value , Make corresponding prompt

10.UART Communication protocol 、9600 Baud rate ,MCU Can pass UART from WT2003H4 Middle readout EV1527 Address .

11. with EV1527 Decoding function , And through UART take EV1527 The decrypted data is returned

12. At present, there are two groups EV1527 The address of . That is, one product can be paired with two groups of remote control addresses

13. Audio frequency response 50HZ-10KHZ. Meet high-quality voice frequency response .

14、 The SNR is greater than 90db.

15、 Low distortion 0.1%,

16、 Low power consumption , High reliability , The output is large , Wide dynamic range , Low distortion , Frequency response width , High quality audio with high signal-to-noise ratio .

17、 coordination 433MHZ RF RF frequency stability , Long transmission distance , Strong penetration ,PLL PLL automatic frequency locking , Digital encryption coding transmission is more reliable and secure , The transmission distance is 25-100 rice , It depends on the transmission power of the remote controller , High compatibility , Basically compatible with the market 433MHZ Module .

Layout matters needing attention ：

1、C1、C2 The filter capacitor shall be as close as possible to IC foot , High frequency capacitor at 103P-104P, Low frequency capacitance 10U above .

2、RF IN Input to WT2003H4 IC The copper sheet is wider than 0.6MM Try to be as short as possible , Antenna accessories 1.5CM There must be no copper in the .

3、DGND And AGND Lead to the power supply and ground for confluence .

As a high-tech enterprise focusing on voice technology research , Always adhere to “ Good service engineers ” Target , Take the standardization of voice interaction devices in the industry as the direction , Committed to making complexity simple , Provide fast voice 、 Intelligent Internet of things application solutions .WT2003HX、WT588F02B And other application design schemes , On the smart alarm clock 、 Smart water cup 、 There are mature application cases in the field of consumer electronics such as atomizer . The application of consumer electronic products is an important development field of the company , future , Weichuang Zhiyin will launch standardized voice chips in more industries , Further enhance the design experience of Engineers , Enabling standardization in the consumer electronics industry .