General Description
The MAX9719A evaluation kit (EV kit) is a fully assembled
and tested circuit board that uses the MAX9719A stereo,
differential audio amplifier to drive a pair of bridge-tied-
load (BTL) speakers in portable audio applications.
Designed to operate from a 2.7V to 5.5V DC power sup-
ply, the EV kit is capable of delivering 2 x 1.1W into a pair
of 8Ωspeakers.
The MAX9719A inputs can accept a common-mode input
voltage of 0.5V through (VCC - 1.2V) from a DC-coupled
source, therefore eliminating the need for input-signal
coupling capacitors. The EV kit provides an option to
bypass the input-signal coupling capacitors when the DC
offset level of the input signals is within an acceptable
range. The MAX9719A EV kit also evaluates the
MAX9719B, MAX9719C, and MAX9719D.
Features
♦Also Evaluates the MAX9719B/C/D (IC and
Component Replacement Required)
♦2.7V to 5.5V Single-Supply Operation
♦Drives 2 x 1.1W Into Stereo 8ΩSpeakers at 1%
THD+N
♦Differential Inputs
♦100nA Shutdown Current (typ)
♦Small 16-Pin TQFN (4mm x 4mm) Package
♦Also Available in 16-Bump UCSP and 16-Pin
TSSOP-EP Packages
♦Fully Assembled and Tested
Quick Start
The MAX9719A EV kit is fully assembled and tested.
Follow the steps listed below to verify board operation.
Do not turn on the power supply until all connections
are completed.
Recommended Equipment
• 2.7V to 5.5V, 3A power supply
• Audio signal source with stereo outputs
• Two 8Ωspeakers
1) Verify that no shunts are installed on jumpers
JU1–JU4 (input-signal coupling capacitors are in
circuit).
2) Verify that a shunt is installed across pins 1 and 2 of
jumper JU5 (EV kit ON).
3) Connect the first 8Ωspeaker across the OUTR+
and OUTR- PC board pads.
4) Connect the second 8Ωspeaker across the OUTL+
and OUTL- PC board pads.
Evaluates: MAX9719A/B/C/D
MAX9719A Evaluation Kit
________________________________________________________________ Maxim Integrated Products 1
19-3370; Rev 0; 7/04
Component List
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Ordering Information
DESIGNATION
QTY
DESCRIPTION
A1 0 MAX9719AEBE (16-pin UCSP)
C1–C4 4
0.47µF ±20%, 16V film chip
capacitors (1206)
Panasonic ECPU1C474MA5
C5 1
10µF ±20%, 6.3V X5R ceramic
capacitor (0805)
TDK C2012X5R0J106M
C6, C7 2
1µF ±10%, 10V X5R ceramic
capacitors (0603)
TDK C1608X5R1A105K
C8 1
0.1µF ±10%, 25V X7R ceramic
capacitor (0603)
TDK C1608X7R1E104K
C9–C12 0 Not installed, capacitors (0603)
R1–R8 8 10kΩ ±1% resistors (0603)
U1 1 MAX9719AETE (16-pin TQFN)
JU1–JU4 4 2-pin headers
JU5 1 3-pin header
None 5 Shunts
None 1 MAX9719A PC board
PART TEMP RANGE IC PACKAGE
MAX9719AEVKIT 0°C to +70°C16-TQFN-EP*
(4mm x 4mm)
*EP = Exposed paddle.
Component Suppliers
SUPPLIER PHONE FAX WEBSITE
Panasonic 714-373-7366 714-737-7323 www.panasonic.com
TDK 847-803-6100 847-390-4405 www.component.tdk.com
Note: Indicate that you are using the MAX9719AEVKIT when contacting these component suppliers.
Evaluates: MAX9719A/B/C/D
5) Connect the positive terminal of the power supply to
the VCC pad and the power-supply ground terminal
to the GND pad.
6) Connect the first output of the stereo audio source
across the INPUTR+ and INPUTR- pads.
7) Connect the second output of the stereo audio
source across the INPUTL+ and INPUTL- pads.
8) Turn on the power supply.
9) Turn on the audio source.
Detailed Description
The MAX9719A EV kit features the MAX9719A stereo
differential audio amplifier, designed to drive a pair of
8Ωspeakers in portable audio applications. The EV kit
operates from a DC power supply that can provide
2.7V to 5.5V and 3A of current.
As configured, the EV kit is set for a gain of 1V/V (0dB) by
gain-setting resistors R1–R8. To set the EV kit to a differ-
ent gain, select other gain-setting resistors. Refer to the
Applications Information section in the MAX9718/
MAX9719 data sheet for selecting the resistors.
Capacitors C9–C12 are used for optionally limiting the
audio signal bandwidth.
Jumper Selection
Shutdown Mode (
SHDN
)
The MAX9719A features a shutdown mode that
reduces the MAX9719A quiescent current to 100nA
(typ). Jumper JU5 controls the shutdown pin (SHDN) of
the MAX9719A IC. See Table 1 for shunt positions.
Bypassing the Input-Signal Coupling Capacitors
(C1–C4)
Jumpers JU1–JU4 provide an option to bypass the
input-signal coupling capacitors C1–C4, respectively,
on the MAX9719A EV kit. See Table 2 for the various
shunt positions. Refer to the Input Filter section of the
MAX9718/MAX9719 data sheet
Evaluating MAX9719B/MAX9719C/MAX9719D
The MAX9719A EV kit can evaluate the MAX9719B,
MAX9719C, and MAX9719D. To evaluate a different IC,
replace U1 with the desired part, and replace the compo-
nents as outlined in Table 3. Refer to the MAX9718/
MAX9719 data sheet for additional information.
MAX9719A Evaluation Kit
2 _______________________________________________________________________________________
Table 1. JU5 Jumper Selection
SHUNT POSITION EV KIT FUNCTION
1-2 (SHDN = high) EV kit enabled
2-3 (SHDN = low) Shutdown mode
None. External logic
connected to SHDN pad.
SHDN driven by external
logic. Shutdown is active low.
Table 2. JU1–JU4 Jumper Selection
Table 3. Component Values for Evaluating Different Versions of the MAX9719
COMPONENT EVALUATING THE
MAX9719A
EVALUATING THE
MAX9719B
EVALUATING THE
MAX9719C
EVALUATING THE
MAX9719D
U1 MAX9719A MAX9719B MAX9719C MAX9719D
R1, R3, R5, R7 10kΩ0Ω0Ω0Ω
R2, R4, R6, R8 10kΩOPEN OPEN OPEN
SHUNT POSITION INPUT-SIGNAL COUPLING
CAPACITORS
Not Installed (default) In circuit
Installed DC-coupled inputs
Evaluates: MAX9719A/B/C/D
MAX9719A Evaluation Kit
_______________________________________________________________________________________ 3
MAX9719A
U1
VCC
INPUTL-
GND
SHDN
2
1
JU5
JU1
R2
10kΩ
1%
C9
OPEN
R4
10kΩ
1%
C10
OPEN
R1
10kΩ
1%
C1
0.47µF
3
GND
VCC
R8
10kΩ
1%
C12
OPEN
R6
10kΩ
1%
C11
OPEN
OUTL+
7
5
9
12
3
8
1
4
OUTL+
BIAS
SHDN
OUTR+
INL-
VCC
GND
INL+
GND
C7
1µF
C5
10µF
C6
1µF
C8
0.1µF
R3
10kΩ
1%
OUTR+
INPUTL+
C2
0.47µF
JU2
INPUTR-
JU3
R5
10kΩ
1%
C3
0.47µF
16
2
INR-
INR+
R7
10kΩ
1%
INPUTR+
C4
0.47µF
JU4
VCC
6
11
14
13 N.C.
VCC
GND
GND
OUTL-
10
OUTL-
15
OUTR-
OUTR-
Figure 1. MAX9719A EV Kit Schematic
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
4_____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2004 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
Evaluates: MAX9719A/B/C/D
MAX9719A Evaluation Kit
Figure 2. MAX9719A EV Kit Component Placement Guide—
Component Side
Figure 3. MAX9719A EV Kit PC Board Layout—Component Side
Figure Figure 4. MAX9719A EV Kit PC Board Layout—Solder
Side
