Texas Instruments TPA6138A2 / TPA6139A2 Headphone Drivers

Texas Instruments TPA6138A2 / TPA6139A2 Headphone Drivers

Texas Instruments TPA6138A2 and TPA6139A2 DirectPath™ headphone drivers are designed for use in PDP / LCD TV applications as well as Blu-Ray™ and DVD players, mini / micro combo systems, and sound cards. The TI TPA6138A2 pop-free stereo headphone amplifier with adjustable gain is designed to allow the removal of the output dc-blocking capacitors for reduced component count and cost. The TPA6138A2 is capable of driving 25 mW into a 32-Ω load with 3.3-V supply voltage. The device has differential inputs and uses external gain-setting resistors that support a gain range of ±1 V/V to ±10 V/V. The TI TPA6139A2 pop-free headphone driver with programmable fixed gain does not require a power supply greater than 3.3V to generate 25mW and does not require a split rail power supply. The TI TPA6139A2 allows the designer to choose from 12 internal programmable gain settings to match the line driver with the Codec output level.

TPA6138A2 Features

Stereo DirectPath™ Headphone Amplifier: 40 mW Into 32 Ω With 3.3-V Supply
Low THD+N < 0.01% at 10 mW Into 32 Ω
High SNR, >90 dB
Differential Input and Single-Ended Output
Adjustable Gain by External Gain-Setting Resistors
Configurable as a Second-Order Low-Pass Filter: Ideal for PWM Audio Sources
Low DC Offset, <1 mV
Ground-Referenced Outputs Eliminate DC-Blocking Capacitors: Reduce Board Area, Reduce Component Cost, Improve THD+N Performance, No Degradation of Low-Frequency Response Due to Output Capacitors
Short-Circuit Protection
Click- and Pop-Reduction Circuitry
External Undervoltage Mute
Active Mute Control for Pop-Free Audio On/Off Control

TPA6139A2 Features

DirectPath™: Eliminates Pop/Clicks, Eliminates Output DC-Blocking Capacitors, 3 V to 3.6 V Supply voltage
Low Noise and THD: SNR > 105 dB at –1x Gain, Typical Vn < 15 µVms 20-20kHz at –1x Gain, THD+N < 0.003% at 10kΩ Load and –1x Gain
25 mW into 600 Ω Load
2 Vrms Output Voltage into 5kΩ Load
Single Ended Input and Output
Programmable Gain Select Reduces Component Count: 13x Gain Values
Active Mute With More Than 80dB Attenuation
Short Circuit and Thermal Protection
±8kV HBM ESD Protected Outputs

Applications