19-4228; Rev 0; 7/08
MAX9744 Evaluation Kit/
Evaluation System
General Description
The MAX9744 evaluation kit (EV kit) is a fully assembled
and tested circuit board that contains the MAX9744
highly efficient 2 x 20W Class D stereo speaker amplifi-
er. The MAX9744 EV kit also includes Windows
®
98SE/2000/XP-compatible software that provides a sim-
ple graphical user interface (GUI) for exercising the
MAX9744’s features.
The MAX9744 evaluation system (EV system) includes
a MAX9744 EV kit and a Maxim CMAXQUSB serial-
interface board.
The CMAXQUSB board connects to a PC’s USB port
and allows the transfer of I
2
C commands to the
MAX9744 EV kit.
Windows is a registered trademark of Microsoft Corp.
PART
Features
o
20W Stereo Output (at 10% THD+N, R
L
= 4Ω,
V
CC
= 13V)
o
Wide Power-Supply Operation (4.5V to 14V)
o
Integrated Volume Control (I
2
C or Stand-Alone
Operation)
o
Optional Control Through USB
o
Proven PCB Layout for Thermal Performance and
EMC
o
Windows 98SE/2000/XP-Compatible Evaluation
Software
o
Fully Assembled and Tested
Evaluate: MAX9744
Ordering Information
TYPE
INTERFACE
Stand-alone
operation or user-
supplied I
2
C
interface
CMAXQUSB board
MAX9744EVKIT+
EV Kit
MAX9744EVCMAXQU
EV System
+
Denotes lead-free and RoHS compliant.
Note:
The MAX9744 EV kit software is included with the
MAX9744 EV kit but is designed for use with the complete EV
system. The EV system includes both the Maxim CMAXQUSB
board and the EV kit. If the Windows software will not be used,
the EV kit board can be purchased without the Maxim
CMAXQUSB board.
Component Lists
MAX9744 EV System
PART
MAX9744EVKIT+
CMAXQUSB
QTY
1
1
DESCRIPTION
MAX9744 EV kit
Serial-interface board
C8–C13
6
DESIGNATION
QTY
DESCRIPTION
0.1µF ±10%, 16V X7R ceramic
capacitors (0603)
TDK C1608X7R1E104K
330µF ±20%, 16V electrolytic
capacitors
Panasonic EEUFM1C331
10µF ±20%, 16V X7R ceramic
capacitors (1206)
Murata GRM318R71C106M
20kΩ ±1% resistors (0603)
Class D stereo amplifier (44 TQFN)
Maxim MAX9744ETH+
MAX9744 EV Kit
DESIGNATION
QTY
DESCRIPTION
REQUIRED COMPONENTS
C4, C5
2
0.47µF ±10%, 16V X7R ceramic
capacitors (0805)
Murata GRM21BR71E474K
1µF ±10%, 16V X5R ceramic
capacitors (0603)
Murata GRM188R61E105K
C23, C24
2
C25, C46
R1–R4
U1
2
4
1
C7, C17–C20
5
________________________________________________________________
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.
MAX9744 Evaluation Kit/
Evaluation System
Evaluate: MAX9744
Component Lists (continued)
DESIGNATION
QTY
DESCRIPTION
100pF ±5%, 16V C0G ceramic
capacitors (0603)
TDK C1608C0G1H101K
0.1µF ±10%, 16V X7R ceramic
capacitors (0603)
TDK C1608X7R1E104K
10µF ±20%, 10V electrolytic
capacitors (A5)
SANYO 10SVP10M
Not installed, ceramic capacitors
(0805)
0.47µF ±10%, 16V X7R ceramic
capacitors (0805)
Murata GRM21BR71E474K
Not installed (0603)
0Ω resistors (0603)
0Ω resistors (1206)
Ferrite bead, 6A (1206)
Black banana jacks
White RCA jack
Red RCA jack
DESIGNATION
J1
J2
JU1–JU5
JU6
JU7
JU8, JU9
L1–L4
R5, R6
R7
R8
R9
R10
R11–R14
R15
SPK_L+,
SPK_R+, VCC
U2
—
—
QTY
1
0
5
1
0
2
4
2
1
0
1
1
4
1
3
1
7
1
DESCRIPTION
Dual-row (2 x 10) 20-pin right-angle
female receptacle
Not installed
3-pin headers
5-pin, 4-way header
Not installed, 2-pin header
2-pin headers
10µH inductors, 3A, 65mΩ
Sumida CDRH127-100
1.2kΩ ±5% resistors (0603)
10kΩ thumbwheel potentiometer
Not installed, resistor (0805)
47kΩ ±5% resistor (0805)
49.9Ω ±1% resistor (0805)
6.8Ω ±1% resistors (0805)
47Ω ±5% resistor (0603)
Red banana jacks
Linear regulator (5 SOT23)
Maxim MAX1615EUK+
Shunts
PCB: MAX9744 Evaluation Kit
OPTIONAL COMPONENTS
C1, C2
2
C3, C6, C14,
C15, C16
5
C21, C22
2
C26–C29
0
C30–C39
C44, C45
FB1, FB2
FB3–FB6
FB7
GND, SPK_L-,
SPK_R-
INL
INR
10
0
2
4
1
3
1
1
Component Suppliers
SUPPLIER
Murata Electronics North America, Inc.
SANYO Electric Co., Ltd.
Sumida Corp.
PHONE
770-436-1300
619-661-6835
847-545-6700
WEBSITE
www.murata-northamerica.com
www.sanyodevice.com
www.sumida.com
TDK Corp.
847-803-6100
www.component.tdk.com
Note:
Indicate that you are using the MAX9744 when contacting these component suppliers.
MAX9744 EV Kit Files
FILE
INSTALL.EXE
MAX9744.EXE
UNINST.INI
TROUBLESHOOTING_USB.PDF
Application program
Uninstalls the EV kit software
USB driver installation help file
DESCRIPTION
Installs the EV kit files on your computer
2
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MAX9744 Evaluation Kit/
Evaluation System
Quick Start (for EV Kit
Stand-Alone Operation)
Recommended Equipment
Before beginning, the following equipment is needed:
• MAX9744 EV kit
•
•
•
One 12V, 5A power supply
Stereo audio source (i.e., CD player)
A pair of 4Ω (or 8Ω) loudspeakers
•
•
•
•
One 12V, 5A power supply
Stereo audio source (i.e., CD player)
A pair of 4Ω (or 8Ω) loudspeakers
A user-supplied Windows 98SE/2000/XP PC with a
spare USB port
Evaluate: MAX9744
Note:
In the following section, software-related items are
identified by bolding. Text in
bold
refers to items directly
from the EV kit software. Text in
bold and underlined
refers to items from the Windows operating system.
Procedure
1) For the MAX9744 EV kit, make sure the shunts of all
jumpers are in the following default positions:
JU1: (2-3)
JU2: (2-3)
JU3: (2-3)
JU4: (1-2)
JU5: (2-3)
JU6: (1-2)
JU8: (Open)
JU9: (Open)
Thumbwheel potentiometer
controls speaker volume
I
2
C interface disabled
I
2
C interface disabled
Normal operation (powered up)
Normal operation (not muted)
FFM mode with f
SW
= 300kHz
No terminator for SYNC_IN pad
Classic PWM modulation
Procedure
1) Visit
www.maxim-ic.com/evkitsoftware
to down-
load the latest version of the EV kit software,
9744Rxx.ZIP. Save the EV kit software to a tempo-
rary folder and uncompress the ZIP file.
2) Install the EV kit software on your computer by run-
ning the INSTALL.EXE program inside the temporary
folder. The program files are copied and icons are
created in the Windows
Start | Programs
menu.
3) On the CMAXQUSB board, ensure that the shunt of
JU1 is in the 3.3V position.
4) Enable the I
2
C pullup resistors on the CMAXQUSB
board by setting the DIP switches at SW1 to the on
position.
5) For the MAX9744 EV kit, make sure the shunts of all
jumpers are in the following default positions:
JU1: (1-2)
JU2: (1-2)
JU3: (1-2)
JU4: (1-2)
JU5: (2-3)
JU6: (1-2)
JU8: (Open)
JU9: (Open)
Using I
2
C interface control
MAX9744
ADD1 = 1
ADD2 = 1
Normal operation (powered-up)
Normal operation (not muted)
FFM mode with f
SW
= 300kHz
No terminator for SYNC_IN pad
Classic PWM modulation
2) Turn the thumbwheel potentiometer clockwise all
the way to minimize speaker volume.
3) Connect the left and right speakers across the
SPK_L+/SPK_L- and SPK_R+/SPK_R- banana
jacks, respectively.
4) Connect the positive terminal of the 12V power sup-
ply to the VCC banana jack, and the ground termi-
nal of the power supply to the GND banana jack.
5) Connect the audio source to the INL and INR RCA
jacks.
6) Turn on the audio source, then turn on the power
supply.
7) Turn the thumbwheel potentiometer counterclock-
wise to increase the volume; the audio signal
should be audible in the speakers.
Quick Start (for EV System)
Recommended Equipment
Before beginning, the following equipment is needed:
• The MAX9744 EV system:
MAX9744 EV kit
Maxim CMAXQUSB board
USB cable (included with CMAXQUSB)
6) Carefully connect the boards by aligning the
MAX9744 EV kit’s 20-pin connector with the
CMAXQUSB board’s 20-pin connector. Gently
press them together. The two boards should be
flush against each other.
7) Connect the left and right speakers across the
SPK_L+/SPK_L- and SPK_R+/SPK_R- banana
jacks, respectively.
8) Connect the positive terminal of the 12V power sup-
ply to the VCC banana jack, and the ground termi-
nal of the power supply to the GND banana jack.
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3
MAX9744 Evaluation Kit/
Evaluation System
Evaluate: MAX9744
9) Connect the audio source to the INL and INR RCA
jacks.
10) Turn on the audio source, then turn on the power
supply.
11) Connect the USB cable from the PC to the
CMAXQUSB board. A
Building Driver Database
window should pop up in addition to a
New
Hardware Found
message if this is the first time
this board is connected to the PC. If you do not see
a window that is similar to the one described
above after 30s, try removing the USB cable from
the CMAXQUSB and reconnect it. Administrator
privileges are required to install the USB device dri-
ver on Windows 2000 and XP. Refer to the TROU-
BLESHOOTING_USB.PDF document included with
the software if you have any problems during this
step.
12) Follow the directions of the
Add New Hardware
Wizard
to install the USB device driver. Choose the
Search for the best driver for your device
option.
Specify the location of the device driver to be
C:\Program Files\MAX9744
(default installation
directory) using the
Browse
button.
13) Start the MAX9744 EV kit software by opening its
icon in the
Start
menu.
14) The EV kit software automatically detects the
MAX9744 I
2
C slave address and resets the
MAX9744. Using the mouse to drag the
Volume
Control
scroll bar to increase the volume, the audio
signal should be audible in the speakers.
Figure 1. MAX9744 EV Kit Software GUI Window
The I2C Address Group Box
The
I2C Address
group box drop-down list selects the
MAX9744’s I
2
C slave address. If multiple devices are
connected to the I
2
C bus, the user can use this drop-
down list to manually change the device’s I
2
C slave
address according to the settings of JU2 and JU3, as
shown in Table 3.
Detailed Description of Software
The MAX9744 EV kit software provides an easy user
interface (see Figure 1) to control the programmable
features of the MAX9744. To start the MAX9744 EV kit
software, double-click the MAX9744 EV kit icon created
during installation. The user must wait approximately 2s
while the MAX9744 EV kit software connects to the
CMAXQUSB board.
PWM Modulation Mode Group Box
The Class D modulation mode can be controlled
through two radio buttons (Classic and
Filterless),
which represent the classic PWM modulation and filter-
less PWM modulation.
Volume Control Group Box
Inside the
Volume Control
group box is the volume
control track bar, which corresponds to the speaker
volume register. By dragging the track bar, the correct
I
2
C/SMBus write operation is generated to update the
speaker volume register of the MAX9744.
4
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MAX9744 Evaluation Kit/
Evaluation System
Detailed Description of Hardware
The MAX9744 EV kit board provides a good thermal
performance and EMC proven layout for evaluating the
MAX9744. The EV kit evaluates the MAX9744ETH+.
The MAX9744 EV kit is a 2 x 20W highly efficient Class D
speaker amplifier system. The EV kit can be driven by any
stereo audio source. The audio input impedance is 20kΩ.
Evaluate: MAX9744
MAX9744 I
2
C Address Selection
There are three possible I
2
C/SMBus addresses (see
Table 3). Note that the I
2
C/SMBus interface is disabled
if both JU2 and JU3 are set in the default position (2-3).
Hardware Shutdown Control
Table 3. The I
2
C Address Configuration
JU3
1-2
1-2
2-3
2-3*
JU2
1-2
2-3
1-2
2-3*
I2C ADDRESS
1001011x
1001010x
1001001x
I
2
C/SMBus interface disabled
MAX9744 EV Kit
MAX9744 EV Kit Stand-Alone Operation
The MAX9744 EV kit can be operated without the
CMAXQUSB command module. To do so, make sure all
the shunts on JU1, JU2, and JU3 are in the 2-3 position.
For more information, see Tables 1 and 3. While in stand-
alone operation mode, the user can rotate the thumb-
wheel potentiometer R7 to adjust the speaker volume.
*Default
position.
Jumper JU4 controls the hardware shutdown function
of the MAX9744 EV kit. This shuts down the entire
MAX9744 and resets all the registers to their power-on
default state. See Table 4 for shunt positions.
Table 1. JU1 Function Description
JU1
1-2
2-3*
FUNCTION
I
2
C interface control speakers’ volume
Thumbwheel potentiometer control speakers’
volume
Hardware Mute Control
*Default
position.
Under stand-alone operation the user can use JU9 to
control the modulation mode, as shown in Table 2.
Remove the shunt of JU9 if using I
2
C/SMBus to control
the EV kit.
Table 4. Hardware Shutdown (SHDN)
Function
JUMPER
JU4
SHUNT
POSITION
1-2*
2-3
SHDN
HARDWARE INPUT
PIN LOGIC LEVEL
High (normal operation)
Low (hardware shutdown)
Power Supply
The MAX9744 EV kit board should be powered by a
user-supplied DC power supply connecting to VCC and
GND. The power supply voltage can range widely from
4.5V to 14V.
*Default
position.
Jumper JU5 controls the speaker mute function of the
MAX9744 EV kit and it overrides the I
2
C interface set-
ting. See Table 5 for shunt positions.
Table 2. PWM Mode Configuration Under
Stand-Alone Operation
JU2
1-2
1-2
2-3
1-2
1-2
2-3
2-3*
2-3
JU3
1-2
2-3
1-2
1-2
2-3
1-2
2-3*
2-3
JU9
Open
Open
Open
1-2
1-2
1-2
Open*
1-2
Classic PWM modulation
Filterless modulation
Invalid
PWM MODE
Controlled by I
2
C/SMBus
interface
Table 5. Hardware Mute Function
JUMPER
JU5
SHUNT
POSITION
1-2
2-3*
MUTE HARDWARE INPUT
PIN LOGIC LEVEL
High (mute)
Low (normal operation)
*Default
position.
*Default
position.
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5