Hi all,
I needed a simple stereo amplifier, working on a 12Vdc power supply, and naturally choose TDA1557 audio amplifier.
The typical circuit is very simple. I have followed the datasheet carefully, but my circuit does not work:
- when the pin12 (Vref) is not connected, the circuit starts to "pump" a lot of current (more than 2 amps) , and although there is no input signal, a loud random noise happens on the speaker
- when i connect this pin to the GND, supplied current seems more reasonnible, but nothing is happening (input signal is not amplified, no output signal).
Can someone help me ?
I needed a simple stereo amplifier, working on a 12Vdc power supply, and naturally choose TDA1557 audio amplifier.
The typical circuit is very simple. I have followed the datasheet carefully, but my circuit does not work:
- when the pin12 (Vref) is not connected, the circuit starts to "pump" a lot of current (more than 2 amps) , and although there is no input signal, a loud random noise happens on the speaker
- when i connect this pin to the GND, supplied current seems more reasonnible, but nothing is happening (input signal is not amplified, no output signal).
Can someone help me ?