TPA6140A2 Class G DirectPath™ Stereo Headphone Amplifier

Texas Instruments and Digi-Key introduce a class G headphone amplifier with built-in I²C volume control

TPA6140A2 Class G DirectPath™ Stereo Headphone AmplifierTexas Instruments TPA6140A2 is a Class-G DirectPath stereo headphone amplifier with built-in I2C volume control. Class-G technology maximizes battery life by adjusting the voltage supplies of the headphone amplifier based on the audio signal level. At low level audio signals, the internal supply voltage is reduced to minimize power dissipation. DirectPath technology eliminates external DC-blocking capacitors.

The device operates from a 2.5V to 5.5V supply voltage. Class-G operation keeps total supply current below 5.0mA while delivering 500µW per channel into 32Ω. Shutdown mode reduces the supply current to less than 3 µA and is activated through the I2C interface. The TPA6140A2 (TPA6140) I2C register map is compatible with the TPA6130A2, simplifying software development.

The amplifier outputs have short-circuit and thermal-overload protection along with ±8kV HBM ESD protection, simplifying end equipment compliance to the IEC 61000-4-2 ESD standard.


  • TI Class-G technology significantly prolongs battery life and music playback time
    • 0.6mA/Ch quiescent current
    • 50% to 80% lower quiescent current than ground referenced class-AB headphone amplifiers
  • DirectPath technology eliminates large output DC-blocking capacitors
    • Outputs biased at 0V
    • Improves low frequency audio fidelity
  • I2C volume control
    • −59dB to +4dB gain
  • Active click and pop suppression
  • Fully differential inputs reduce system noise
    • Also configurable as single-ended inputs
  • SGND pin eliminates ground loop noise
  • Wide power supply range: 2.5V to 5.5V
  • 100dB power supply noise rejection
  • Short-circuit current limiter
  • Cellular phones and music phones
  • Portable media and MP3 players
  • Portable CD/DVD players


ImageManufacturer Part NumberDescriptionAmplifier TypeOutput TypeMax Output Power x Channels @ LoadAvailable QuantityView Details
TPA6140A2YFFEVM datasheet linkEVALUATION MODULE FOR TPA6140A2TPA6140A2YFFEVMEVALUATION MODULE FOR TPA6140A2Class GHeadphones, 2-Channel (Stereo)32mW x 2 @ 32 Ohm3 - Immediate
3 - Factory Stock
TPA6140A2YFFEVM product page link
Published: 2009-07-09