SLOS312C – JUNE 2000 – REVISED JUNE 2004
350-mW MONO AUDIO POWER AMPLIFIER WITH DIFFERENTIAL INPUTS
• Fully Specified for 3.3-V and 5-V Operation
• Wide Power Supply Compatibility
2.5 V – 5.5 V
• Output Power for RL = 8 Ω
– 350 mW at VDD = 5 V
– 250 mW at VDD = 3.3 V
• Ultralow Supply Current in Shutdown
Mode . . . 0.15 µA
• Thermal and Short-Circuit Protection
• Surface-Mount Packaging
– PowerPAD™ MSOP
D OR DGN PACKAGE
SHUTDOWN 1 8 VO-
BYPASS 2 7 GND
IN+ 3 6 VDD
IN- 4 5 VO+
The TPA321 is a bridge-tied load (BTL) audio power amplifier developed especially for low-voltage applications
where internal speakers are required. Operating with a 3.3-V supply, the TPA321 can deliver 250 mW of
continuous power into a BTL 8-Ω load at less than 1% THD+N throughout voice band frequencies. Although this
device is characterized out to 20 kHz, its operation was optimized for narrower band applications such as cellular
communications. The BTL configuration eliminates the need for external coupling capacitors on the output in
most applications, which is particularly important for small battery-powered equipment. This device features a
shutdown mode for power-sensitive applications with a quiescent current of 0.15 µA during shutdown. The
TPA321 is available in an 8-pin SOIC surface-mount package and the surface-mount PowerPAD™ MSOP, which
reduces board space by 50% and height by 40%.
From System Control
4 IN -
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.
PowerPAD is a trademark of Texas Instruments.
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 © 2000–2004, Texas Instruments Incorporated