MAX9789_09 Datasheet, PDF (1/28 Pages) Maxim Integrated Products – Windows Vista-Compliant, Stereo Class AB Speaker Amplifiers and DirectDrive Headphone Amplifiers

19-0606; Rev 3; 9/09
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
General Description
The MAX9789/MAX9790 combine a stereo, 2W Class AB
speaker power amplifier with a stereo 100mW
DirectDrive^® headphone amplifier in a single device. The
MAX9789/MAX9790 are designed for use with the
Microsoft Windows Vista^® operating system and are fully
compliant with Microsoft’s Windows Vista specifications.
The headphone amplifier features Maxim’s patented^†
DirectDrive architecture that produces a ground-refer-
enced output from a single supply to eliminate the need
for large DC-blocking capacitors, as well as save cost,
board space, and component height. A high +90dB
PSRR and low 0.002% THD+N ensures clean, low-distor-
tion amplification of the audio signal.
Separate speaker and headphone amplifier control
inputs provide independent shutdown of the speaker
and headphone amplifiers, allowing speaker and head-
phone amplifiers to be active simultaneously, if
required. The industry-leading click-and-pop suppres-
sion circuitry reduces audible transients during startup
and shutdown cycles.
The MAX9789 features an internal LDO that can be used
as a clean power supply for a CODEC or other circuits.
The LDO output voltage is set internally at 4.75V or can
be adjusted between 1.21V and 4.75V using a simple
resistive divider. The LDO is protected against thermal
overloads and short circuits while providing 120mA of
continuous output current and can be enabled indepen-
dently of the audio amplifiers.
By disabling the speaker and headphone amplifiers, and
the LDO (for MAX9789), the MAX9789/MAX9790 enter
low-power shutdown mode and draw only 0.3µA.
The MAX9789/MAX9790 operate from a single 4.5V to
5.5V supply and feature thermal-overload and output
short-circuit protection. Devices are specified over the
-40°C to +85°C extended temperature range.
Features
o Microsoft Windows Vista Compliant
o Class AB 2W Stereo BTL Speaker Amplifier
o 100mW DirectDrive Headphone Amplifier
Eliminates Costly, Bulky DC-Blocking Capacitors
o Excellent RF Immunity
o Integrated 120mA LDO (MAX9789)
o High +90dB PSRR, Low 0.002% THD+N
o Low-Power Shutdown Mode
o Click-and-Pop Suppression
o Short-Circuit and Thermal-Overload Protection
o Available in 32-Pin Thin QFN (5mm x 5mm x
0.8mm) Package
Ordering Information
PART
PIN-PACKAGE INTERNAL LDO t_ON (ms)
MAX9789AETJ+ 32 TQFN-EP*
Yes
100
MAX9789BETJ+** 32 TQFN-EP*
Yes
25
MAX9789CETJ+ 32 TQFN-EP*
Yes
100
MAX9790AETJ+ 32 TQFN-EP*
No
100
MAX9790BETJ+** 32 TQFN-EP*
No
25
Note: All devices are specified over the -40°C to +85°C extended
temperature range.
+Denotes a lead-free/RoHS-compliant package.
*EP = Exposed pad.
**Future product—contact factory for availability.
Simplified Block Diagrams
SPEAKER SUPPLY HEADPHONE SUPPLY
4.5V TO 5.5V
3.0V TO 5.5V
SPKR_INR
Applications
SPKR_INL
MAX9789
Notebook Computers
HP_INR
Tablet PCs
Portable Multimedia Players
Pin Configurations appear at end of data sheet.
†_{U.S. Patent # 7,061,327.}
Windows Vista is a registered trademark of Microsoft Corp.
HP_INL
SPKR_EN
HP_EN
MUTE
GAIN1
GAIN2
4.5V TO 5.5V
LDO
1.21V TO 4.75V
DirectDrive is a registered trademark of Maxim Integrated
Products, Inc.
Simplified Block Diagrams continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.