MAX9790AETJ+ Maxim Integrated Products, MAX9790AETJ+ Datasheet - Page 14

• Manufacturer Part Number: MAX9790AETJ+
• Description: IC AMP AUDIO 2W STER AB 32TQFN
• Manufacturer: Maxim Integrated Products
• Series: DirectDrive™r
• Type: Class ABr

Specifications of MAX9790AETJ+

• Output Type: 2-Channel (Stereo) with Stereo Headphones
• Max Output Power X Channels @ Load: 2W x 2 @ 4 Ohm; 100mW x 2 @ 16 Ohm
• Voltage - Supply: 4.5 V ~ 5.5 V
• Features: Depop, Mute, Short-Circuit and Thermal Protection, Shutdown
• Mounting Type: Surface Mount
• Package / Case: 32-TQFN Exposed Pad
• For Use With: MAX9789AEVKIT+ - EVALUATION KIT FOR MAX9789A
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
The MAX9789/MAX9790 combine a 2W BTL speaker
amplifier with an 100mW DirectDrive headphone amplifi-
er. These devices feature comprehensive click-and-pop
suppression and programmable four-level speaker ampli-
fier gain control. The MAX9789/MAX9790 feature high
+90dB PSRR, low 0.002% THD+N, industry-leading click-
and-pop performance, low-power shutdown mode, and
excellent RF immunity. The MAX9789 incorporates an
integrated LDO that serves as a clean power supply for a
CODEC or other circuits.
The MAX9789/MAX9790 is Microsoft Windows Vista com-
pliant. See Table 1 for a comparison of the Microsoft
Windows Vista premium mobile specifications and
MAX9789/MAX9790 specifications.
The speaker amplifiers use BTL architecture, doubling the
voltage drive to the speakers and eliminating the need for
DC-blocking capacitors. The output consists of two sig-
nals, identical in magnitude, but 180° out of phase.
The headphone amplifiers use Maxim’s patented
DirectDrive architecture to eliminate the bulky output
DC-blocking capacitors required by traditional head-
phone amplifiers. A charge pump inverts a positive
supply (CPV
The headphone amplifiers operate from these bipolar
supplies with their outputs biased about GND. The
benefit of the GND bias is that the amplifier outputs no
longer have a DC component (typically V
feature eliminates the large DC-blocking capacitors
Table 1. Windows Premium Mobile Vista Specifications vs. MAX9789/MAX9790
Specifications
Note: THD+N, DYNAMIC RANGE, and CROSSTALK should be measured in accordance with AES-17 audio measurements standards.
Dual Mode is a trademark of Maxim Integrated Products, Inc.
14
Analog Line Output
Jack (R
FS = 0.707V
Analog Headphone
Out Jack (R
FS = 0.300V
DEVICE TYPE
______________________________________________________________________________________
L
= 10kΩ,
L
RMS
RMS
= 32Ω,
DD
)
)
) to create a negative supply (CPV
THD+N
Dynamic range with
signal present
Line output crosstalk
THD+N
Dynamic range with
signal present
Headphone output
crosstalk
Detailed Description
REQUIREMENT
DD
/ 2). This
WINDOWS PREMIUM MOBILE Vista
SS
).
SPECIFICATIONS
[20Hz, 20kHz]
[20Hz, 20kHz]
[20Hz, 20kHz]
[20Hz, 20kHz]
≤ -80dB FS,
≤ -60dB FS,
A-weighted
A-weighted
≤ -65dB FS
≤ -45dB FS
≤ -50dB
≤ -50dB
required with conventional headphone amplifiers to
conserve board space and system cost, as well as
improve low-frequency response.
The MAX9789/MAX9790 feature programmable speak-
er amplifier gain, allowing the speaker gain to be set by
the logic voltages applied to GAIN1 and GAIN2, while
the headphone amplifiers feature a fixed 3.5dB gain.
Both amplifiers feature an undervoltage lockout that
prevents operation from an insufficient power supply
and click-and-pop suppression that eliminates audible
transients on startup and shutdown. The amplifiers
include thermal overload and short-circuit protection.
An additional feature of the speaker amplifiers is that
there is no phase inversion from input to output.
The MAX9789’s low-dropout (LDO) linear regulator can
be used to provide a clean power supply to a CODEC
or other circuitry. The LDO can be enabled indepen-
dently of the audio amplifiers. Set LDO_EN = V
enable the LDO or set LDO_EN = GND to disable the
LDO. The LDO is capable of providing up to 120mA
continuous current and features Maxim’s Dual Mode™
feedback, easily enabling a fixed 4.75V output or a
user-adjustable output. When LDO_SET is connected
to GND, the output is internally set to 4.75V. The output
voltage can be adjusted from 1.21V to 4.75V by con-
necting two external resistors as a voltage divider, at
LDO_SET (Figure 1).
Low-Dropout Linear Regulator
TYPICAL PERFORMANCE
MAX9789/MAX9790
[20Hz, 20kHz]
[20Hz, 20kHz]
[20Hz, 20kHz]
[20Hz, 20kHz]
(MAX9789 Only)
A-weighted
A-weighted
-97dB FS,
-89dB FS,
-94dB FS
-77dB FS
-77dB
-74dB
DD
to