MAX9722AEVKIT Maxim Integrated Products, MAX9722AEVKIT Datasheet - Page 2

• Manufacturer Part Number: MAX9722AEVKIT
• Description: Audio Modules & Development Tools MAX9722A KIT MAX9722A KIT
• Manufacturer: Maxim Integrated Products

Specifications of MAX9722AEVKIT

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

5) Connect the left output of the audio source to the
6) Connect the ground of the audio source to the
7) Connect the right output of the audio source to the
8) Connect the ground of the audio source to the
9) Turn on the power supply.
10) Turn on the audio source.
The MAX9722A EV kit features the MAX9722A differential
stereo headphone amplifier with DirectDrive, which is
designed to directly drive a 16Ω or 32Ω stereo head-
phone in portable audio applications. The EV kit oper-
ates from a DC power supply that can provide 2.4V to
5.5V and 500mA of current. The EV kit accepts two sets
of differential or single-ended audio inputs. The amplifier
is able to deliver 70mW per channel into a 16Ω load or
130mW per channel into a 32Ω load.
The EV kit can also be used as an audio line driver to
provide 2V
When used in this way, the EV kit features a remote
ground-sensing network to reduce any ground loop
noise at the receiving device (see the Remote Ground
Sensing section).
Jumper JU1 controls the shutdown pin (SHDN) of the
MAX9722A. See Table 1 for jumper positions.
Jumper JU2, resistors R9 and R10 configure the remote
ground-sensing feature for the MAX9722A EV kit. See
Table 2 for jumper shunt positions and approximate
resistor values.
Note: When using the remote ground-sensing feature,
remove resistors R3, R4, R7, and R8. Install a 10kΩ
resistor at the R9 and R10 PC board pads. Replace R11
with a 10Ω resistor. In this mode of operation, the input
signals on the INPUTL- and INPUTR- pads are refer-
enced to the EV kit PGND pad and are single ended. If
headphones are used in this configuration, channel-to-
channel isolation may be degraded.
The MAX9722A EV kit can evaluate the MAX9722B. To
evaluate the MAX9722B, replace U1 with a MAX9722B
and replace the components as outlined in Table 3.
MAX9722A Evaluation Kit
2
INPUTL- pad.
INPUTL+ pad.
INPUTR- pad.
INPUTR+ pad.
_______________________________________________________________________________________
RMS
into a 1kΩ load from a single 5V supply.
Detailed Description
Evaluating the MAX9722B
Remote Ground Sensing
Shutdown Mode
Jumper Selection
(SHDN)
Refer to the MAX9722A/MAX9722B data sheet for addi-
tional information on using the MAX9722B as a head-
phone amplifier or as an audio line driver.
Table 1. JU1 Jumper Selection
Table 2. JU2 Jumper Selection
Table 3. Component Values for
Evaluating the MAX9722B
1-2 (SHDN = high)
2-3 (SHDN = low)
None. External controller
connected to SHDN pad
(logic level).
Not
installed
(default)
Installed
POSITION
COMPONENT
SHUNT
R1, R5
R2, R6
R3, R7
R4, R8
SHUNT POSITION
R10
R11
JU2
U1
R9
Open
10kΩ
R10
R9,
INPUTS; OUTPUT
LOCAL GROUND
DIFFERENTIAL
REFERRED TO
R3, R4,
EV KIT USES
R7, R8
Not installed
Open
10kΩ
MAX9722B
Open
15kΩ
30kΩ
Open
Open
0Ω
0Ω
R11
EV kit enabled
Shutdown mode
SHDN driven by external
controller. Shutdown is active
low.
(Ω)
10
0
configured
C onfi g ur ed
SENSING
EV KIT FUNCTION
REMOTE
GND
Not
SENSES REMOTE
INPUTS, OUTPUT
SINGLE-ENDED
EV KIT USES
MAX9722B
GROUND
Installed
Open
Open
Open
D i ffer enti al
i np uts,
outp ut
r efer enced to
l ocal g r ound
S i ng l e- end ed
i np uts,
outp ut senses
remote g round
30kΩ
15kΩ
10Ω
FUNCTION
0Ω
EV KIT