High Quality Voice Recorder using IC aPR33A

In embedded or electronics projects there is a need of voice guidance or the people making project in DTMF needs IVR system to give voice reply at the output. So most of the people prefer IPOD, MP3 player, or SDCARD Module. All the things are costly and difficult in connecting to the system. Sometimes even there is problem in sound generating some kind of noise.

The systematic or typical way is to use specialized voice circuitry which can be operated by any microcontroller and the message can be played by the microcontroller logic controlling the chip.

This can be easily done using IC APR33A. This is new IC in the market. It can store recording upto 11 Minutes. And it can be operated upto message mode of 1/2/4/8, depending on the requirement of user

Image of aPR33A IC based Voice Recording Module

Fig. 1: Image of aPR33A IC based Voice Recording Module

APR33A Pin Diagram & Description

Today’s consumers demand the best in audio/voice. They want crystal-clear sound wherever they are in whatever format they want to use. APLUS delivers the technology to enhance a listener’s audio/voice experience.

The aPR33A series are powerful audio processor along with high performance audio

Analog-to-digital converters (ADCs) and digital-to-analog converters (DACs). The aPR33A series are a fully integrated solution offering high performance and unparalleled integration with analog input, digital processing and analog output functionality. The aPR33A series incorporates all the functionality required to perform demanding audio/voice applications.

High quality audio/voice systems with lower bill-of-material costs can be implemented with the aPR33A series because of its integrated analog data converters and full suite of quality-enhancing features such as sample-rate convertor.

The aPR33A series C2.0 is specially designed for simple key trigger, user can record and playback the message averagely for 1, 2, 4 or 8 voice message(s) by switch, it is suitable in simple interface or need to limit the length of single message, e.g. toys, leave messages system, answering machine etc. Meanwhile, this mode provides the power-management system. Users can let the chip enter power-down mode when unused. It can effectively reduce electric current consuming to 15uA and increase the using time in any projects powered by batteries.

Pin Diagram of aPR33A IC for Voice Recording

Fig. 2: Pin Diagram of aPR33A IC for Voice Recording

PIN DESCRIPTION:

Pin Configuration of aPR33A IC for Voice Recording

Fig. 3: Pin Configuration of aPR33A IC for Voice Recording

MESSAGE MODE

In fixed 1/ 2/ 4/ 8 message mode (C2.0), user can divide the memory averagely for 1, 2, 4 or 8 message(s). The message mode will be applied after chip reset by the MSEL0 and MSEL1 pin.

Please note the message should be recorded and played in same message mode, we CAN NOT guarantee the message is complete after message mode changed. For example, user recorded 8 messages in the 8-message mode; those messages can be played in 8-message mode only. If user changed to 1, 2 or 4 message mode, system will discard those messages.

8-Message Mode

The memory will be divided to 8 messages averagely when both MSEL0 and MSEL1 pin float after chip reset.

4-Message Mode

The memory will be divided to 4 messages averagely when MSEL0 pin connected to VSS and

MSEL1 pin float after chip reset

2-Message Mode

The memory will be divided to 2 messages averagely when MSEL1 pin connected to VSS and

MSEL0 pin float after chip reset.

1-Message Mode

The memory will be for 1 message when both MSEL0 and MSEL1 pin connected to VSS after chip reset.

Record & Playback Message

RECORD MESSAGE

During the /REC pin drove to VIL, chip in the record mode.

When the message pin (M0, M1, M2 … M7) drove to VIL in record mode, the chip will playback “beep” tone and message record starting.

The message record will continue until message pin released or full of this message, and the chip will playback “beep” tone 2 times to indicate the message record finished.

If the message already exist and user record again, the old one’s message will be replaced.

The following fig. showed a typical record circuit for 8-message mode. We connected a slide-switch between /REC pin and VSS, and connected 8 tact-switches between M0 ~ M7 pin and VSS. When the slide-switch fixed in VSS side and any tact-switch will be pressed, chip will start message record and until the user releases the tact-switch.

PLAYBACK MESSAGE

During the /REC pin drove to VIH, chip in the playback mode.

When the message pin (M0, M1, M2 … M7) drove from VIH to VIL in playback mode, the message playback starting.

The message playback will continue until message pin drove from VIH to VIL again or end of this message.

The following fig. showed a typical playback circuit for 8-message mode. We connected a slide-switch between /REC and VSS, and connected 8 tact-switches between M0 ~ M7 and VSS. When the slide-switch fixed in float side and any tact-switch will be pressed, chip will start message playback and until the user pressed the tact-switch again or end of message.

PCB Files & Components

PCB Files

PCB Layout of aPR33A IC based Voice Recording Module

Fig. 4: PCB Layout of aPR33A IC based Voice Recording Module

Refer to attached the PDF file for original design of 1:1 scale

Components and value in reference to identity of pcb file in above diagram

R1 = 4.7K

R2 =100K

R3 =47K

R4 =1K

R5 =4.7K

R6 =4.7K

R7 =470E

C1 =1Nf/ 102

C2 =100NF/ 104

C3 =100NF/ 104

C4 =100UF 25V

C5 =100NF/104

C6 =10UF 63V

C7 =100UF 25V

C8 =100NF/104

C9 =1UF 50V

C10 =1NF/ 102

C11 =100NF/104

C12 =100NF/104

C13 =100UF 25V

U1 =APR33A

L1 TO L5 = LINK / JUMPER

Project Source Code

###

#include<reg51.h>

sbit a=P3^0;

sbit b=P3^1;

sbit c=P3^2;

sbit d=P3^3;

sbit e=P3^4;

sbit f=P3^5;

sbit g=P3^6;

sbit h=P3^7;


void delay(unsigned int x)

{

unsigned int i,j;

for(i=0;i<x;i++)

for(j=0;j<1275;j++);

}


void main()

{

P3=0x00; //Set P3 as output port

P1=0xff; //set P1 as input port


while(1)

{


if(P1==0X88)   //if received data 88

{

a=1; //play message 1

delay(1);

a=0;

}


else if(P1==0X48) //if received data 48

{

b=1; //play message 2

delay(1);

b=0;

}


if(P1==0XC8) //if received data c8

{

c=1; //play message 3

delay(1);

c=0;

}


if(P1==0X28) //if received data 28

{

d=1; //play message 4

delay(1);

d=0;

}


if(P1==0Xa8) //if received data a8

{

e=1; //play message 5

delay(1);

e=0;

}


if(P1==0x68) //if received data 68

{

f=1; //play message 6

delay(1);

f=0;

}


if(P1==0xe8) //if received data e8

{

g=1; //play message 7

delay(1);

g=0;

}


if(P1==0x18) //if received data 18

{

h=1; //play message 8

delay(1);

h=0;

}
}

}
###