MAX9788 Evaluation Kit
The EV kit accepts single-ended or a differential audio
input and provides a fully differential output. The audio
Quick Start
Recommended Equipment
input source is amplified to drive greater than 14V
into a ceramic speaker.
P-P
• 5V, 1A power supply
• Audio source (i.e., CD player, MP3 player)
Customizing the Gain
The MAX9788 EV kit is shipped with a gain of +12dB.
Change the resistors (R1–R4) to customize the gain of
the EV kit (refer to the MAX9788 IC data sheet for
details).
• One ceramic speaker (recommended suppliers:
Murata, Taiyo Yuden)
Procedure
The MAX9788 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 con-
nections are completed.
Jumper Selection
Shutdown Mode (SHDN)
Jumper JU1 controls the shutdown pin (SHDN) of the
MAX9788 IC. The shutdown pin is also controlled by
an external logic controller connected to the EV kit
SHDN pad. Remove the shunt from jumper JU1 before
connecting an external controller to the SHDN pad.
See Table 1 for shunt positions.
1) Install a shunt across pins 1-2 of jumper JU1 (EV kit
ON).
2) Connect the ceramic speaker across the OUT- and
OUT+ pads.
3) Connect the positive terminal of the power supply to
the VCC pad and the ground terminal to the GND
pad.
Evluates:MAX978
Table 1. Shutdown Mode, JU1 Jumper
Selection
4) Connect the positive terminal of the audio source to
the IN+ pad.
MAX9788 SHDN
PIN CONNECTED
TO
5) Connect the negative terminal of the audio source
to the IN- pad. Connect the IN- pad to GND if the
audio source is single ended.
SHUNT
POSITION
EV KIT FUNCTION
1-2*
2-3
VDD
GND
EV kit enabled
ꢁ) Connect the ground terminal of the audio source to
the GND pad.
Shutdown mode
7) Turn on the audio source.
8) Turn on the power supply.
SHDN driven by external
logic controller.
Shutdown is active low
and 1.8V logic compliant.
External logic
controller
None
Detailed Description
The MAX9788 EV kit features the MAX9788 Class G
amplifier IC, designed to drive a ceramic speaker in a
BTL configuration. The EV kit operates from a DC power
supply that provides 2.7V to 5.5V and 1A of current.
*Default position.
2
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