Audio Voice Recording ISD1820 Module Without Loudspeaker

Features:

• Up to 10 seconds of audio can be recorded and played back by default

• Operating voltage: 2.6V – 5.5V

• Controllable via MCU or onboard buttons

• Playback via edge or level activation

• Integrated microphone

• On-chip speaker driver for 8-ohm speakers

• Recording duration and sampling rate adjustable up to 20 seconds by changing an external resistor

• Automatic power-off mode

Principle of Work:

• Press and hold the REC button to start recording; keep it pressed until recording is complete.

• Release the REC button to stop recording.

• Select PLAYE for edge-triggered playback of the entire message, or PLAYL for level-triggered playback that continues while the button is pressed.

• The recorded message will play back each time the P-E jumper is triggered or when power is cycled.

• When the FT jumper is shorted in FT mode, the microphone input is routed directly to the speaker output for live playback.

Pinout of the Module:

 VCC – DC 2.4V to 5.5V
GND – Ground
FT – Feed-Through mode, routes microphone directly to speaker
REC / REC (Button) – Active-HIGH record input; must remain HIGH for the duration of recording
P-E / PLAY-E (Button) – Edge-activated playback until end of message
P-L / PLAY-L (Button) – Level-activated playback while input remains HIGH
SP+ / SP- – Direct speaker output for speakers down to 8 ohms (not a Serial Parallel Interface)
MIC – Microphone input to the on-chip pre-amplifier

Applications:

• Voice recorders

• Microcontroller-based audio playback

• Sound recording systems

• Talking toys and dolls

Circuit:

In the basic connection configuration, the module can only record 10 seconds of audio.

Library:

No library is required for this module to operate.

Code:

int Rec = 11;
int Play = 13;

void setup() {
pinMode(Rec, OUTPUT);
pinMode(Play, OUTPUT);
}
void loop() {
digitalWrite(Rec, HIGH);
delay(10000);
digitalWrite(Rec, LOW);
delay(50);
digitalWrite(Play, HIGH);
delay(50);
digitalWrite(Play, LOW);
delay(10000);
}

Technical Details:

• Operating voltage: 2.4V – 5.5V DC

• Directly drives 8-ohm, 0.5W speakers (not included)

• Module dimensions: 8 x 6 x 3 cm

• PCB size: 4.3 x 3.8 cm (1.7 x 1.5 inches)

Comparisons:

This module is simple to use and avoids complex configuration options, making it suitable for most basic voice recording and playback applications. The audio quality is adequate for voice messages, and the compact design allows easy integration. For applications requiring longer recordings or file-based audio storage, a more advanced module such as an MP3 decoder or audio shield, should be used instead