AUDIO MODULATED MATRIX LED DRIVER
The IS31FL3732 is a compact LED driver for 144
single LEDs. The device can be programmed via an
I2C compatible interface. The IS31FL3732 offers two
blocks each driving 72 LEDs with 1/9 cycle rate. The
required lines to drive all 144 LEDs are reduced to 18
by using the cross-plexing feature optimizing space on
the PCB. Additionally each of the 144 LEDs can be
dimmed individually with 8-bit allowing 256 steps of
To reduce CPU usage up to 8 frames can be stored
with individual time delays between frames to play
small animations automatically. LED frames can be
modulated with audio signal.
IS31FL3732 is available in QFN-40 (5mm×5mm)
package. It operates from 2.7V to 5.5V over the
temperature range of -40°C to +85°C.
TYPICAL APPLICATION CIRCUIT
Supply voltage range: 2.7V to 5.5V
1MHz I2C-compatible interface
144 LEDs in dot matrix
Individual blink control
Individual PWM control 256 steps
Individual on/off control
Global current control 256 steps
Cascade for synchronization of chips
8 frames memory for animations
Picture mode and animation mode
Auto intensity breathing during the switching of
LED frames displayed can be modulated with
audio signal intensity
LED light intensity can be modulated with audio
QFN-40 (5mm×5mm) package
Mobile phones and other hand-held devices for
LED in home appliances
Figure 1 Typical Application Circuit
Note 1: For the mobile applications the IC should be placed far away from the mobile antenna in order to prevent the EMI.
Note 2: The average current of each LED is 3.2mA when REXT = 20kΩ. The LED current can be modulated by the REXT. Please refer to the
detail information in Page 18.
Note 3: The thermal pad should be connected to GND.
Note 4: The VIO should be 1.8V≤ VIO ≤VCC. And it is recommended to be equal to VOH of the micro controller. For example, if VOH=1.8V, set
VIO=1.8V is recommended.
Integrated Silicon Solution, Inc. – www.issi.com
Rev. C, 04/20/2017