IS31BL3506A BOOST CONVERTER LED BACKLIGHT DRIVER DESCRIPTION ABSOLUTE MAXIMUM RATINGS IS31BL3506A LED driver demo board is used to 5.5V power supply demonstrate and evaluate the IS31FL3506A. Caution: Do not exceed the conditions listed above, otherwise IS31BL3506A is a boost converter featuring an the board will be damaged. integrated MOSFET switch designed for driving series strings of LED or other device. The device regulates the LED load current is set using an external, low value PROCEDURE sensing resistor. The device adjusts the PWM duty cycle of the switch to maintain the voltage at the FB pin The IS31BL3506A evaluation board is fully assembled at a value of 0.3V. and tested. Follow the below steps to verify operation. Caution: Do not turn on the power supply until all connections are completed. FEATURES 1) Connect the ground terminal of the power supply Supply voltage: 2.7V~5.5V to the GND and the positive terminal to the VCC. Drive series strings of 9 LEDs Or connect the DC power to the connector (DC IN). PWM or DC voltage dimming Frequency of PWM is 500Hz ~ 500kHz 2) Turn on the power supply and pay attention to the 1.0MHz high speed switching frequency supply current. If the current exceeds 500mA, please check for circuit fault. DFN-8 (2mm2mm) package 3) Press Level+ or Level- button to change current of white LEDs, the intensity of LEDs will be in 1 level QUICK START (lowest) when power on. 4) The button (SD/EN) controls the IS31BL3506A Shutdown or Enable. EVALUATION BOARD OPERATION The IS31BL3506A evaluation board performs constant output current with PWM dimming control. The evaluation board uses a MCU generating PWM signal at EN pin adjusting the LEDs current. The current level is displayed by Dual Digit Display. Note: IS31BL3506A solely controls the white LEDs function on the evaluation board. SOFTWARE SUPPORT Figure 1: Photo of IS31BL3506A Evaluation Board JP1 is set to close circuit by default. If it is set to open, the onboard MCU will stop working. The MCU pin RECOMMENDED EQUIPMENT which drives the EN pin of the LED driver will be set to High Impedance. An external driving signal can be 5.0V, 2A power supply connected to the TP5 connecting point to control the IS31BL3506A LED driver. Please refer to the datasheet to get more information about IS31BL3506A. Lumissil Microsystems www.lumissil.com 1 Rev. A, 07/12/2012 IS31BL3506A BOOST CONVERTER LED BACKLIGHT DRIVER ORDERING INFORMATION Part No. Temperature Range Package IS31BL3506A-DLS2-EB -40C ~ +85C (Industrial) DFN-8, Lead-free Table1: Ordering Information For pricing, delivery, and ordering information, please contacts Lumissils analog marketing team at analog Lumissil.com or (408) 969-6600. Figure 2: IS31BL3506A Application Schematic Lumissil Microsystems www.lumissil.com 2 Rev. A, 07/12/2012