Part Number: LM4950
Sorry to bother you.
If we use LM4950, speaker is 4ohm/2w (Use SE)
Is it based on the following figure to determine the output voltage??
The AMP front-end input (AUDIO CODEC output) should be 1.2~1.1 Vrms
Will the setting of gain as shown below be correct ??(speaker is 4ohm / 2W)
Please take a look at my responses below and let me know if you have additional questions or comments on it.
If we use LM4950, speaker is 4ohm/2w (Use SE) Is it based on the following figure to determine the output voltage??
Yes, figure 23 of datasheet shows the output power that you may reach for a RL = 4ohms (SE operation) with a THD+N = 10% and THD+N = 1%. You would need to select the power supply according to your power requirements.
This resistors configuration results in a gain of ~16.3. Could you provide details about the input that you will be using and the expected output?
Best regards,Luis Fernando Rodríguez S.
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In reply to Luis Fernando Rodriguez S.:
Thanks for your reply.
Please help confirm the LM4950 schematic (Single-Ended)
LM4950_0815-Edit.pdfThe line below CN9 is anti-pops
Input spec as follows
In reply to Shu-Cheng LIN:
Have any update on here?
Sorry for the delay on this.
I already reviewed the schematic and everything seems to be in order. I didn't find anything to modify.
The configured gain in this case is given by Rf / RI = (48.7K / 20K) = 2.435. If a 1.2 Vrms signal is used, you should be able to reach almost 2.9Vrms at the output. This would be enough to reach 2W output power with a 4ohms load.
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