Dear Sir,
As per datasheet of MAX9711, it was recommended to use 100uH inductor in parallel with 10Ohm resistor at Out+ pin. Is there any specific 100uH inductor part number along with 10Ohm resistors which are recommended for this purpose?
In our application, this device is driving 300 Ohm speaker, with 1.2Vrms output audio level to be used in military radio application. Recently we have seen lot of MAX9711 being burnt-out and it had to be replaced. This had never happened before in my long career as an audio engineer, and this is not the first time I am using MAX9711. There are some of our military radio products which are in production having MAX9711 implemented and it is working perfectly, and only this new product is creating issue. The output speaker is same in all the products.
The OUT+ & GND are used to drive 300 Ohm handset speaker when it is connected to the radio. But when 8 Ohm loudspeaker is connected to the radio, OUT+ & OUT- are used.
It is requested to identify the root cause of this.
Also one more query, do the capacitors at the output of this amplifier changes the phases? We had to remove one capacitor at OUT+ so that OUT- & OUT+ are in phase.
Schematic is attached herewith.
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