Windows Vista-Compliant, Stereo Class AB Speaker

Amplifiers and DirectDrive Headphone Amplifiers

________________________________________________________________

Maxim Integrated Products

1

Ordering Information

19-0606; Rev 3; 9/09

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.

General Description

The MAX9789/MAX9790 combine a stereo, 2W Class AB

speaker power amplifier with a stereo 100mW

MAX9789/MAX9790 are designed for use with the

compliant with Microsoft’s Windows Vista specifications.

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

Applications

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.

PART

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

Simplified Block Diagrams

MAX9789

SPKR_EN

HP_EN

MUTE

GAIN1

GAIN2

SPEAKER SUPPLY

4.5V TO 5.5V

HEADPHONE SUPPLY

3.0V TO 5.5V

LDO

4.5V TO 5.5V

SPKR_INR

SPKR_INL

HP_INR

HP_INL

1.21V TO 4.75V

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

Notebook Computers

Tablet PCs

Portable Multimedia Players

Windows Vista is a registered trademark of Microsoft Corp.

Pin Configurations appear at end of data sheet.

†U.S. Patent # 7,061,327.

Simplified Block Diagrams continued at end of data sheet.

DirectDrive is a registered trademark of Maxim Integrated

Products, Inc.