TPA6138A2PWR Datasheet, PDF (1/18 Pages) Texas Instruments – DirectPath™ Headphone Driver With Adjustable Gain

TPA6138A2
www.ti.com
SLOS704A – JANUARY 2011 – REVISED MAY 2011
DirectPath™ Headphone Driver With Adjustable Gain
Check for Samples: TPA6138A2
FEATURES
1
•23 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
• Space-Saving TSSOP Package
APPLICATIONS
• LCD and PDP TV
• Blu-ray Disc™, DVD Players
• Set-Top Boxes
• Mini/Micro Combo Systems
• Sound Cards
• Laptops
DESCRIPTION
The TPA6138A2 is a pop-free stereo headphone
amplifier designed to allow the removal of the output
dc-blocking capacitors for reduced component count
and cost. The device is ideal for single-supply
electronics where size and cost are critical design
parameters.
Designed using TI’s patented DirectPath™
technology, 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 supports a gain range of ±1
V/V to ±10 V/V. Gain can be configured individually
for each channel. The device can also be configured
as a second-order low-pass filter and is ideal for
interfacing with PWM audio sources. Audio output
compiles with ±8-kV IEC ESD protection, requiring
just a simple resistor-capacitor ESD protection circuit.
The TPA6138A2 has built-in active-mute control for
pop-free audio on/off control. The TPA6138A2 has an
external undervoltage detector that mutes the output
when the power supply is removed, ensuring a
pop-free shutdown.
Using the TPA6138A2 in audio products can reduce
component count considerably compared to
traditional headphone amplifiers. The TPA6138A2
does not require a split-rail power supply or a dc
blocking capacitor. The TPA6138A2 integrates its
own charge pump to generate a negative supply rail
that provides a clean, pop-free ground-biased audio
signal.
The TPA6138A2 is available in a 14-pin TSSOP.
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
DirectPath, FilterPro are trademarks of Texas Instruments.
2
Blu-ray Disc is a trademark of Blu-ray Disc Association.
3
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2011, Texas Instruments Incorporated