
TPA721
700-mW MONO LOW-VOLTAGE AUDIO POWER AMPLIFIER
SLOS231D – NOVEMBER 1998 – REVISED OCTOBER 2002
1
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
Fully Specified for 3.3-V and 5-V Operation
Wide Power Supply Compatibility
2.5 V – 5.5 V
Output Power for R
L
= 8
– 700 mW at V
DD
= 5 V, BTL
– 250 mW at V
DD
= 3.3 V, BTL
Integrated Depop Circuitry
Thermal and Short-Circuit Protection
Surface-Mount Packaging
– SOIC
– PowerPAD
MSOP
description
The TPA721 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 TPA721 can deliver 250-mW of
continuous power into a BTL 8-
load at less than 0.6% THD+N throughout voice band frequencies. Although
this device is characterized out to 20 kHz, its operation is optimized for narrower band applications such as
wireless 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 supply current of 7
μ
A during shutdown. The
TPA721 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%.
Audio
Input
Bias
Control
VDD
700 mW
6
5
7
VO+
VDD
1
2
4
BYPASS
IN –
VDD/2
CI
RI
CS
CB
RF
SHUTDOWN
VO–
8
GND
From System Control
3
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.
Copyright
2002, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
1
2
3
4
8
7
6
5
SHUTDOWN
BYPASS
IN+
IN–
V
O
–
GND
V
DD
V
O
+
D OR DGN PACKAGE
(TOP VIEW)
PowerPAD is a trademark of Texas Instruments.