Evaluates: MAX13330/MAX13331
Quick Start
Required Equipment
• One pair of 8Ω to 32Ω headphones
• One variable DC power supply capable of supply-
ing between 4V and 5.5V at 500mA
• One stereo audio source
Procedure
The MAX13331 EV kit is fully assembled and tested.
Follow the steps below to verify board operation.
Caution: Do not turn on the power supply until all
connections are completed.
1) Plug the headphones into the 3.5mm headphone
jack (J1).
2) Ensure that the stereo audio source is turned off.
3) Connect the disabled stereo audio source through
the RCA phono jacks (P1 and P2).
4) Ensure that a shunt is installed on jumper JU1.
5) Connect the 4V to 5.5V DC power supply to the
VDD and PGND pads.
6) Turn on the DC power supply.
7) Verify that the audio source level is low.
8) Enable the stereo audio source.
9) Verify that the audio source signal is clearly heard
from the headphones.
Detailed Description of Hardware
The MAX13331 EV kit is a stereo, single-supply head-
phone amplifier. The input impedance is 15kΩ. The
-3dB corner frequencies are approximately 10Hz and
greater than 22kHz and are dependent on components
R1/C1 and R2/C2. The MAX13331 EV kit has a gain of
approximately 1.5 and can be powered with a 4V to
5.5V supply
The EV kit provides two RCA phono jacks (P1 and P2)
to facilitate the connection of an audio source. In addi-
tion, both outputs (OUTL and OUTR) are routed to a
stereo headphone jack (J1), facilitating output monitor-
ing. Shutdown control of OUTL and OUTR is also pro-
vided through jumper JU1.
Shutdown Control
The MAX13331 EV kit provides jumper JU1 to disable
the outputs, OUTL and OUTR (see Table 1 for shut-
down shunt positions). Both OUTL and OUTR are rout-
ed to the headphone jack (J1).
Layout Considerations
To optimize the audio performance of the MAX13331, it is
important to follow these layout guidelines. The MAX13331
EV kit uses two ground planes to minimize switching noise.
The two planes are star-connected at one point (JU2 pad).
Capacitors C5, C6, C8, C12, C13, and C14 should be
placed close to the IC. Refer to the MAX13331 IC data
sheet for additional layout considerations.
The MAX13331 EV kit is a four-layer design, but it is
possible to design the MAX13331 circuit on to a two-
layer board. For a two-layer design, optimize the signal
and power ground planes by maximizing the area and
connecting each plane, as close as possible, to its
respective IC pin.
MAX13331 Evaluation Kit
2 _______________________________________________________________________________________
Murata Electronics North America, Inc. 770-436-1300 www.murata-northamerica.com
TDK Corp. 847-803-6100 www.component.tdk.com
