TPA2008D2_15 Datasheet, PDF (1/26 Pages) Texas Instruments – 3-W STEREO CLASS-D AUDIO POWER AMPLIFIER WITH DC VOLUME CONTROL

TPA2008D2
www.ti.com
SLOS413C – JULY 2003 – REVISED MAY 2004
3-W STEREO CLASS-D AUDIO POWER AMPLIFIER WITH DC VOLUME CONTROL
FEATURES
• 3 W Per Channel into 3-Ω Speakers
(THD+N = 10%)
– < 0.045% THD at 1.5 W, 1 kHz, 3-Ω Load
• DC Volume Control With 2-dB Steps From
-38 dB to 20 dB
• Filter Free Modulation Scheme Operates
Without a Large and Expensive LC Output
Filter
• Extremely Efficient Third Generation 5-V
Class-D Technology
– Low Supply Current, 7 mA
– Low Shutdown Control, 1 µA
– Low Noise Floor, -80 dBV
– Maximum Efficiency into 3 Ω, 78%
– Maximum Efficiency into 8 Ω, 88%
– PSRR, -70 dB
• Integrated Depop Circuitry
• Operating Temperature Range, -40°C to 85°C
• Space-Saving, Surface Mount PowerPAD™
Package
APPLICATIONS
• LCD Projectors
• LCD Monitors
• Powered Speakers
• Battery Operated and Space Constrained
Systems
100
90
80
70
60
50
40
30
20
10
0
0
EFFICIENCY
vs
OUTPUT POWER
8 Ω Speaker
4 Ω Speaker
3 Ω Speaker
V_DD = 5 V
No Filter
0.5
1
1.5
2
2.5
3
3.5
P_O − Output Power − W
DESCRIPTION
The TPA2008D2 is a third generation 5-V class-D
amplifier from Texas Instruments. Improvements to
previous generation devices include: dc volume con-
trol, lower supply current, lower noise floor, higher
efficiency, smaller packaging, and fewer external
components. Most notably, a new filter-free class-D
modulation technique allows the TPA2008D2 to di-
rectly drive the speakers, without needing a low-pass
output filter consisting of two inductors and three
capacitors per channel. Eliminating this output filter
saves approximately 30% in system cost and 75% in
PCB area.
The improvements and functionality make this device
ideal for LCD projectors, LCD monitors, powered
speakers, and other applications that demand more
battery life, reduced board space, and functionality
that surpasses currently available class-D devices.
A chip-level shutdown control limits total supply
current to 1 µA, making the device ideal for bat-
tery-powered applications. Protection circuitry in-
creases device reliability: thermal and short circuit.
Undervoltage shutdown saves battery power for more
essential devices when battery voltage drops to low
levels.
The TPA2008D2 is available in a 24-pin TSSOP
PowerPAD™package.
TOTAL HARMONIC DISTORTION + NOISE
vs
20
10
V_DD = 5 V
R_L = 3 Ω
Gain = 0 dB
OUTPUT POWER
f = 1 kHz
1
f = 20 kHz
0.1
f = 20 Hz
0.01
0.01
0.1
1
4
P_O − Output Power − W
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 © 2003–2004, Texas Instruments Incorporated