We have a TPA2025D1 in a design driving a 8 Ohm speaker at around 1.5W. I need to modify the design so that the PA output has an electronic switch to switch between two speakers
1. the original 8 Ohm speaker at 1.5W
2. a smaller speaker (called receiver in phone terminology) 28 to 32 Ohm at 20mW (we will reduce the output from the codec to achieve the 20mW speaker output)
I don't have problem using the PA to drive 8 Ohm speaker but I am not sure whether there is problem driving the 28 to 32 Ohm speaker at low power. What parameters will degrade? Efficiency? THD? Will the PA become unstable? The data sheet does not say anything about load higher than 8 Ohm. Thanks.