LM4802B_14 Datasheet, PDF (1/24 Pages) Texas Instruments – Audio Power Amplifier Series Audio Power Amplifier with Boost Converter to Drive Ceramic Speakers

LM4802B, LM4802BLQBD
www.ti.com
SNAS243C – MAY 2004 – REVISED MARCH 2005
LM4802B Boomer™ Audio Power Amplifier Series Audio Power Amplifier with Boost
Converter to Drive Ceramic Speakers
Check for Samples: LM4802B, LM4802BLQBD
FEATURES
1
•23 Pop & Click Circuitry Eliminates Noise During
Turn-On and Turn-Off Transitions
• Low, 2μA (Max) Shutdown Current
• Low, 12mA (Typ) Quiescent Current
• 12Vp-p Mono BTL Output, Load = 2μF + 30Ω,
V_DD = 3V
• Short Circuit Protection
• Unity-Gain Stable
• External Gain Configuration Capability
APPLICATIONS
• Cellphone
• PDA
KEY SPECIFICATIONS
• Quiescent Power Supply Current, 12mA (Typ)
• BTL Voltage Swing
(2μF + 30Ω load, 1% THD+N,
V_DD = 3V), 12Vp-p (typ)
• Shutdown Current, 2μA (max)
DESCRIPTION
The LM4802B integrates a Boost Converter with an
Audio Power Amplifier to drive Ceramic Speakers in
portable applications. When powered by a 3V supply,
it is capable of forcing 12Vp-p across a 2μF + 30Ω
bridge-tied-load (BTL) with less than 1% THD+N.
Boomer audio power amplifiers were designed
specifically to provide high quality output power with a
minimal amount of external components. The
LM4802B does not require bootstrap capacitors, or
snubber circuits. Therefore it is ideally suited for
portable applications requiring high output voltage
and minimal size.
The LM4802B features a low-power consumption
shutdown mode. Additionally, the LM4802B features
an internal thermal shutdown protection mechanism.
The LM4802B contains advanced pop & click circuitry
that eliminates noises which would otherwise occur
during turn-on and turn-off transitions.
The LM4802B is unity-gain stable. Its gain is set by
external resistors.
Connection Diagram
NC
NC
NC
VDD
NC
Shutdown 1
GND
28 27 26 25 24 23 22
1
21
2
20
3
19
4
18
5
17
6
16
7
15
8 9 10 11 12 13 14
IN+
GND
Bypass
Shutdown 2
Vo2
NC
NC
Figure 1. LM4802BLQ (5x5)
Top View
See Package Number NJB0028A
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.
Boomer is a trademark of Texas Instruments.
2
All other trademarks are the property of their respective owners.
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 © 2004–2005, Texas Instruments Incorporated