I am designing a widget that has to have a speaker output (low power, between 1W and 2W, 8 Ohms, low-quality) with the limitation that one end of the speaker must be grounded.

There are lots of audio amplifier ICs to choose from, but all I could find have BTL outputs (they drive both ends of the speaker). Can I use such an amplifier (for example Class-AB TPA6211A1 or Class-D PAM8012) in a single-ended output configuration? Will I only loose maximum power output?

I have regulated 3.3V and unregulated 7.2V (2x li-ion) available. The signal source is a 3.3V MCU. Its DAC can generate single-ended and differential signals. The MCU also has I2S interfaces.

  • \$\begingroup\$ LM386 only drives one end of the speaker. You need a big cap to block the DC. \$\endgroup\$ – Mattman944 Jun 25 '19 at 17:37
  • \$\begingroup\$ If you want 2W single-ended, you'll need an 8W BTL output amplifier, half the volts, one quarter the power \$\endgroup\$ – Neil_UK Jun 25 '19 at 18:21
  • \$\begingroup\$ What are your available power supply rails? We know you want less than \$2\:\text{W}\$, but how much less can you accept? What range of speaker impedances must you be able to handle? And what's driving the amplifier, exactly? \$\endgroup\$ – jonk Jun 25 '19 at 18:50

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