IS31BL3506B-STLS2-EB ISSI

IS31BL3506B 1.0MHZ BOOST CONVERTER WITH 35V INTERNAL MOSFET SWITCH DESCRIPTION ABSOLUTE MAXIMUM RATINGS IS31BL3506B is a boost converter featuring an 5.5V power supply integrated MOSFET switch designed for driving series Caution: Do not exceed the conditions listed above, otherwise strings of LED or other device. Input operating voltage the board will be damaged. range is 2.7V~5.5V. The device regulates the LED load current is set using an external, low value sensing resistor. The device adjusts the PWM duty cycle of the PROCEDURE switch to maintain the voltage at the FB pin at a value of 0.2V. The IS31BL3506B operates at a constant The IS31BL3506B evaluation board is fully assembled switching frequency of 1.0MHz to allow for small and tested. Follow the below steps to verify operation. component size. IS31BL3506B features an over Caution: Do not turn on the power supply until all connections voltage shutdown pin which prevents the output are completed. voltage from exceeding 35V (typ.) in the case of an 1) Connect the Power Supply ground terminal to the open circuit condition. PCB GND input pin and the positive terminal to the PCB VCC input pin. Or connect a 5V FEATURES wall-mount DC power out plug (center power) to the PCB connector (CON1 / DC IN). Supply voltage: 2.7V~5.5V 2) Turn on the power supply and pay attention to the Built-in soft start supply current. If the current exceeds 2A, please Drive series strings of 8 LEDs check for circuit fault. PWM or DC voltage dimming Frequency of PWM is 500Hz ~ 500kHz 1.0MHz high speed switching frequency EVALUATION BOARD OPERATION 200mV feedback voltage The WLED light intensity is adjusted by the onboard Integrated high power MOSFET MCU (LPC936) which generates a PWM signal to the Over voltage protection IS31BL3506B EN pin 4. There are 32 intensity levels -40C ~ +85C working temperature range with the lowest set as the power on default. Pressing SOT23-6 package the Level+ key will increase the intensity level while pressing the Level- key will decrease the level. The 7-segment LED (DIG1) will show the corresponding QUICK START light intensity level. The SD/EN key is used to toggle between shutdown and enable modes. The LED+ and LED- are test points to monitor the output voltage. LED CURRENT SETTING When the IS31BL3506B is used for LED driving applications, the LED current flows through external feedback resistors R and R to regulate the LED 1 2 current. The internal feedback regulation point is 0.2V. The max current is calculated by the following: I V / R and R R / R (R =1 if zero 2 MAX FB SET SET 1 2 ohm resistor used). For accurate LED current, resistors should be 1% or better tolerance. SOFTWARE SUPPORT Figure 1: Photo of IS31BL3506B Evaluation Board JP1 is connected by default. Open it to disable the onboard MCU which will place the IS31BL3506B EN pin in High impedance. An external driving signal can RECOMMENDED EQUIPMENT then be connected to TP5 connector to control the IS31BL3506B LED driver. Please refer to the SW 5.0V, 2A power supply program for LPC936 code example. Please refer to the datasheet to get more information about IS31BL3506B. Lumissil Microsystems www.lumissil.com 1 Rev. A, 07/23/2013 Seg2 dp A G BC Seg1 D F E IS31BL3506B 1.0MHZ BOOST CONVERTER WITH 35V INTERNAL MOSFET SWITCH ORDERING INFORMATION Part No. Temperature Range Package IS31BL3506B-STLS2-EB -40C ~ +85C (Industrial) SOT23-6, 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. TP3 D1 L1 VCC DFLS240 22uH LED+ TP1 C2 U1 C4 CON1 VCC 0.1uF 6 1 C3 NC VCC LX DC IN 1uF/50V C1 D2 ~ D10 10uF EN 4 R6 EN 5 0R OUT R7 100K R2 TP2 2 3 0R GND FB LED- R4 R1 R3 IS31BL3506B NC 10R NC TP4 R5 PWM DIG1 NC C5 NC 2281BS TP5 EN 1 PWM 2 R14 U3 3V A 1K 3 21 P0.0 VDD R15 B 1K 26 5 P0.1 P1.6 TP6 R16 13 P2.2 U2 C 1K 25 14 3V 5 P0.2 P2.3 VCC 3V R17 15 P0.5 4 P2.4 1 5 D 1K 24 16 P0.4 VDD VOUT 3 P0.3 P2.5 RST R18 28 2 P2.7 3 C7 C8 GND E 1K P0.4 23 4 SD 1 P0.4 P1.7 C6 10nF 1uF 9 R19 P3.0 1uF 2 4 ICP F 1K 22 8 P0.5 GND BP P0.5 P3.1 R20 G 20 1K P0.6 LDO R21 17 G2 P1.1/RXD 3V dp 1K 19 P0.7 VCC 6 RST RST/P1.5 VCC U4 1 Seg2 R11 R10 R9 R8 18 G1 D1 TXD/P1.0 3 8 100K 100K 100K 100K D2 S1 K1 SD/EN 12 27 EN P1.2/T0/SCL P2.6 7 S1 K2 R12 R13 Seg1 Level- 11 2 PWM P1.3/INT0/SDA P2.1 100K 100K G1 2 6 G1 S2 K3 Level+ 10 P1.4/INT1 G2 4 5 G2 S2 JP1 OPEN=EXT CTRL 1 7 P2.0 VSS APM4953 LPC936 Figure 2: IS31BL3506B Application Schematic Lumissil Microsystems www.lumissil.com 2 Rev. A, 07/23/2013 1 10 e f 2 9 d Seg1 3 8 c b 4 7 g a 5 6 dp Seg2