TEA2025 BRIDGE AND STEREO AUDIO AMPLIFIER CIRCUIT DIAGRAM

BRIDGE AND STEREO AUDIO AMPLIFIER 

The TEA2025 is an integrated circuit used for audio amplification, capable of operating in both bridge and stereo modes. It is often used in small audio applications such as portable speakers and radios.

TEA2025 Stereo Audio Amplifier Circuit Diagram

Below is a general description of how you might set up a stereo audio amplifier using the TEA2025.

Components Needed:

1. TEA2025 IC
2. Electrolytic Capacitors (various values)
3. Ceramic Capacitors (various values)
4. Resistors (various values)
5. Potentiometer (for volume control)
6. Speakers
7. Audio Input (e.g., 3.5mm jack)
8. Power Supply (e.g., 9V or 12V)

Circuit Description:

1. Power Supply:

   • Connect the positive terminal of the power supply to pin 9 of the TEA2025, and the ground terminal to pin 3.

2. Input Stage:

   • Connect your audio input (e.g., from a 3.5mm jack) to the input capacitors (typically 1µF or 2.2µF electrolytic capacitors).
   • These capacitors are then connected to pins 1 and 7 for the left and right channels, respectively.

3. Feedback and Gain Setting:

   • Resistors and capacitors are connected between the feedback pins (pins 2, 6, 8, and 10) and the input pins to set the gain of the amplifier.
   • For example, you might use a 1kΩ resistor and a 100µF capacitor in series for each channel.

4. Output Stage:

   • The outputs for the left and right channels are taken from pins 4 and 11, respectively.
   • Connect these to your speakers through a series of capacitors (typically 470µF) to block DC and pass the amplified audio signal.

5. Grounding:

   • Ensure that all ground pins (3, 5) are connected to the circuit's ground.

TEA2025 Pin Configuration:

• Pin 1, 7: Left and right input
• Pin 2, 6, 8, 10: Feedback and gain control
• Pin 3, 5: Ground
• Pin 4, 11: Left and right output
• Pin 9: Vcc (Power supply)
• Pin 13, 14: Inputs for bridged mode (optional)

Circuit Diagram Example:

plaintext
          +9V
           |
           |
          Pin 9
           |
     --------------
    |   TEA2025   |
    |             |
    |       Pin 4 ----> (Output L) -----> 470uF Capacitor ----> Speaker L
    |       Pin 11 ----> (Output R) -----> 470uF Capacitor ----> Speaker R
    |             |
    |      Pin 1 <---- (Audio Input L) <--- 1uF Capacitor <--- 3.5mm Jack
    |      Pin 7 <---- (Audio Input R) <--- 1uF Capacitor <--- 3.5mm Jack
    |             |
    |      Pin 2,6,8,10 <-- Gain Resistor/Capacitor Network
    |             |
    |       Pin 3 ----> GND
    |       Pin 5 ----> GND
     --------------

This diagram outlines the basic connections. Adjust component values based on your specific requirements.

This setup can also be easily adapted for bridge mode by connecting the inputs to different pins and configuring the outputs accordingly.

If you need a more detailed circuit diagram or specific component values, I can help further!

DESCRIPTION 

The TEA2025B/D is a monolithic integrated circuit in 12+2+2 Power dip and 12+4+4 SO, intended for use as dual or bridge power audio amplifier portable radio cassette players


FEATURES 

• DUAL OR BRIDGE CONNECTION MODES 
• FEW EXTERNAL COMPONENTS 
• SUPPLY VOLTAGE DOWN TO 3V 
• HIGH CHANNEL SEPARATION 
• VERY LOW SWITCH ON/OFF NOISE 
• MAX GAIN OF 45dB WITH ADJUST EXTERNAL RESISTOR 
• SOFT CLIPPING 
• THERMAL PROTECTION 
• 3V < VCC < 15V „ P = 2 · 1W, VCC = 6V, RL = 4Ω 
• P = 2 · 2.3W, VCC = 9V, RL = 4Ω
•  P = 2 · 0.1W, VCC = 3V, RL = 4Ω

Bridge Application (Power dip)

Stereo Application (Power dip)

APPLICATION INFORMATION

•  Input Capacitor Input capacitor is PNP type allowing source to be referenced to ground. In this way no input coupling capacitor is required. However, a series capacitor (0.22 µF)to the input side can be useful in case of noise due to variable resistor contact. 
• Bootstrap The bootstrap connection allows to increase the output swing. The suggested value for the bootstrap capacitors (100µF) avoids a reduction of the output signal also at low frequencies and low supply voltages. 

• Voltage Gain Adjust 

STEREO MODE

 
The voltage gain is determined by on-chip resistors R1 and R2 together with the external RfC1 series connected between pin 6 (11) and ground. The frequency response is given approximated

With Rf=0, C1=100 µF, the gain results 46 dB with pole at f=32 Hz. THE purpose of Rf is to reduce the gain. It is recommended to not reduce it under 36 dB

BRIDGE MODE

The bridge configuration is realized very easily thanks to an internal voltage divider which provides (at pin 1) the CH 1 output signal after reduction. It is enough to connect pin 6 (inverting input of CH 2) with a capacitor to pin 1 and to connect to ground the pin 7. The total gain of the bridge is given by:

and with the suggested values (C1 = C2 = 100 µF, Rf= 0) means: Gv = 52 dB with first pole at f = 32 Hz