G
N
D
EN
VI
O
G
N
D
EN
VI
O
User's Guide
SNVU211 – March 2013
LM3639AYFQEVM User's Guide
1
Introduction
The Texas Instruments LM3639YFQAEVM evaluation module (EVM) helps designers evaluate the
operation and performance of the LM3639A Single Chip 40V Bac 1.5A Flash LED Driver. The low-
voltage, high-current flash LED driver is a synchronous boost which provides the power for a single flash
LED at up to 1.5A or dual LEDs at up to 750 mA each. The high-voltage backlight driver is a dual-output
asynchronous boost which powers dual LED strings at up to 40V and 30 mA per string.
The EVM contains one LM3639A Single Chip 40V Bac 1.5A Flash LED Driver (See
).
Table 1. Device and Package Configurations
FLASH LED DRIVER
IC
PACKAGE
U1
LM3639AYFQT
YFQ0020HGA
2
Setup
This section describes the jumpers and connectors on the EVM as well as how to properly connect, set up
and use the LM3639A EVM.
2.1
Input/Output Connector Description
Input / GND - These are the power input terminals for the driver. The terminal block provides a power
(VIN) and ground (GND) connection to allow the user to attach the EVM to a cable harness.
EN - This is the jumper used to enable the LED driver. The driver will be enabled when the EN pin is high
(VIO) and disabled when it is low (GND). The EN pin is connected to ground via a 300 k
Ω
resistor internal
to the LM3639A
Figure 1. Enable Jumper Settings
VIO - This pin provides power for the I
2
C lines (Clock & Data) and for the EN pin. It is recommended that
this pin is connected to the VIN pin. If desired, it can be connected to the 3.3V line provided by the USB
interface connector. In this configuration, communication via the I
2
C interface may not be possible if the
supply voltage to the LED driver is below approximately 3V.
2
LM3639AYFQEVM User's Guide
SNVU211 – March 2013
Copyright © 2013, Texas Instruments Incorporated
