KIB3402F

SEMICONDUCTOR TECHNICAL DATA White LED Step-Up Converter The KIB3402F is a monolithic step-up DC/DC converter specifically designed to drive white LEDs with a constant current from Li-ion cell. Relative large 320mV feedback voltage & it’s high accuracy help you setting LED current with a external resistor. KIB3402F is available in a extremely low profile & small TS-6 package. A 4.7 H inductor is sufficient for most application. A F KIB3402F BICD LINEAR INTEGRATED CIRCUIT E K B K 1 6 2 5 DIM A B C D E D F G H I J K L FEATURES Inherently Matched LED Current. High Efficiency : 85% (max.) L 3 4 MILLIMETERS _ 2.9 + 0.05 _ 1.6 + 0.05 _ 0.7 + 0.05 _ 0.4 + 0.05 _ 2.8 + 0.07 _ 1.9 + 0.05 0.95 _ 0.16 +0.05 _ 0.05 + 0.05 MIN 0.21 _ 0.6 + 0.07 0.4 Built in a open circuits protection for the LEDs fail. Drives Up to four LEDs without external zener diode. Drives Up to six LEDs with external zener diode. Built in a N-channel MOSFET Switch. Fast 1.1MHz(typ.) Switching Frequency. Uses Tiny 1mm Tall Inductors. Bulit in Thermal protection. Wide Dimming control range : 25%~100%. Extremely low height & small Packaging. C G G J APPLICATIONS Celluars Phones PDAs Digital Cameras MP3 Players, Color Displays Marking 6 5 4 Type Name 1 TYPICAL APPLICATION L1 4.7 µH~10 µH D1 CONVERSION EFFICIENCY 87.00 LED1 VIN 6 C1 1µF VCC 3 SW OVD 2 85.00 EFFICIENCY (%) LED2 LED3 LED4 FB 4 C2 1µF 83.00 81.00 79.00 77.00 75.00 ON OFF KIB3402F 1 CTL GND Shutdown and Dimming control 5 R1 21.5Ω 0 0 5 10 C1, C2 : X5R OR X7R DIELECTRIC D1 : KEC KDR730E/KDR720E (Low VF ) L1 : MURATA LQH32CN100K53L OR EQUIVALENT LOAD CURRENT (mA) Figure1. 4Series White LED Driver in Thin TS6 2006. 4. 20 Revision No : 0 I J H TS6 Lot No. 402 2 3 Vin 3.0V 3.6V 4.3V 15 20 25 1/6 KIB3402F BLOCK DIAGRAM VCC 6 SW 3 2 OVD + + - One Shot + OUT + OUT VRef _ + One Shot + Vth _ + - + - OUT + - CTL 1 ADC 320mV 5 GND 4 FB(Rsense) figure 2. KIB3402F Block Diagram MAXIMUM RATINGS (Ta=25 ) SYMBOL VCC VSW VOVD Topr Tstg Tj RATING -0.3 ~ 6.0 -0.3 ~ 22 -0.3 ~ 22 -40 ~ 85 -40 ~ 150 150 UNIT V V V CHARATERISTICS Input Voltage Switching pin Voltage OVD pin Voltage Operating temperature range Storage temperature range Maximum Junction temperature RECOMMENDED OPERATING CONDITIONS (Topr=-40~85 CHARATERISTICS Input Voltage CTL pin voltage for full LED current CTL pin voltage to shutdown chip CTL pin input pulse width LED Current CTL Response Delay (When Power ON.) SYMBOL VCC VCTL H VCC=3.0V VCTL L tPW(CTL) IF Tpd CTL ) MIN. 2.8 2.7 TYP. 20 MAX. 5.5 0.5 UNIT V V V CONDITION - Both Positive and Negative pulse VCC=3.6V, RSENSE=16 Topr =25 , Four LED , 33 2 2006. 4. 20 Revision No : 0 2/6 KIB3402F ELECTRICAL CHARACTERISTIC (Topr=-40~85 , VCC=2.8~5.5V, RSENSE=16 CHARATERISTICS Input Voltage Supply Current Feedback Voltage CTL Pin Bias Current Switching Frequency Switching Pin Current Switch RDS(ON) Switch Leak Current OVD Pin Voltage OVD Pin Leak Current Thermal Shutdown Switching Pin OVP CTL pin voltage for Full LED Current CTL pin voltage to shutdown Chip Feedback Bias Current Maximum Duty Cycle SYMBOL VCC ICC VFB ICTL fOSC IO(SW) RON IOZ(SW) VOVD IOZ(OVD) TSD VO(SW) VCTL H VCTL L IFB Dmax VCC = 3.0V IO(SW) 400 - , unless otherwise noted.) CONDITION VCC = 3.6V, VCTL=3.6V VCTL = 0V VCC=VCTL=3.0V, Topr = 25 , L =10 H VCC = 3.0V, VCTL = 3.0V VCTL = 3.0V MIN. 2.8 294 0.77 16 25 2.7 85 TYP. 0.9 0.5 320 20 1.1 400 0.7 0.5 20 0.5 150 0.5 90 MAX. 5.5 1.5 1 346 1.43 1.5 1 22 1 180 0.5 1 % V V V V UNIT V PIN FUNCTIONS NO. SYMBOL FUNCTION AND CONNECTION. Control pin : Shutdown or dimming control. Connect external enable or dimming circuits. Shutdown mode (IF = 0) : VCTL2.5V Rate Of the LED Current Open-Circuits Protection In the case of output open circuit, when LEDs are disconnected from the circuit or the LEDs fail, the feedback voltage will be zero. Example : RSENSE = 16 0 0 25 ~ 100 5 ~ 20 100 20 % mA Dimming Control There are 4 different type of dimming control circuits: 0.30 KDR412 20 500 mA 2.50 1.70 0 Figure5. 6LEDs driver with Open-circuit protection. Table 2 CTL pin Voltage vs ILED 2006. 4. 20 Revision No : 0 RSENSE 21.5Ω R1 16Ω GND 5 4/6 KIB3402F VIN 6 C1 1µF L1 4.7 µH~10 µH D1 3 SW OVD 2 LED1 LED2 LED3 LED4 FB 4 RSENSE 21.5Ω C2 1µF Vsw 5V/Div VCC DC 1 CTL KIB3402F GND VCTL 2V/Div 5 (A) 1kHz (2ms/Div) Figure 7. Using a PWM Signal to CTL pin. 0 Figure6. Using a DC Signal to CTL pin. 2. Using a PWM Signal to CTL pin. With the PWM signal applied to the CTL pin, the KIB3402F is turned on or off by the signal. Typical frequency range of the PWM signal is 15kHz to 30kHz. The switching waveforms of the CTL pin PWM control are shown in Figure 7(A) and 7(B) 3. Using a DC Voltage to FB pin. The dimming control using a DC control voltage to FB pin of the KIB3402F is shown in Figure. The LED current can be varied applying a DC voltage to the FB pin. The voltage can come from a filtered PWM signal. It can be used to replace the variable DC Voltage source in dimming control. L1 D1 VIN L1 4.7 µH~10 µH D1 6 VCC 3 SW OVD 2 LED1 LED2 LED3 LED4 R1 RSENSE C2 1µF VIN 6 C1 1µF VCC 3 SW OVD 2 LED1 LED2 LED3 LED4 FB 4 C2 1µF C1 1µF KIB3402F 1 CTL FB 4 GND PWM 1 CTL KIB3402F GND 5 R2 5 RSENSE 21.5Ω 0 0 DC 0 0 0 Figure8. Using DC Voltage to FB pin. 4. Using a Logic Signal to FB pin. For applications that need to adjust the LED current in discret steps, a logic signal can be used as shown in Figure 9. L1 D1 Vsw 5V/Div VIN 6 3 SW LED2 OVD 2 LED3 LED4 FB 4 C1 1uF GND Rdim RSENSE KTK5132V LOGIC C2 1uF LED1 VCTL 2V/Div VCC KIB3402F (A) 1kHz (2ms/Div) 1 CTL 5 0 Figure9. Using a Logic Signal to FB pin. 2006. 4. 20 Revision No : 0 5/6 KIB3402F VFB vs VCTL 350 VFB Efficicncy vs Temperature 95 90 EFFICICNCY (%) 85 80 75 70 65 60 Vin=4.3V Vin=3.6V Vin=3.0V 300 250 V FB (mV) 200 150 100 50 0 0 1 2 3 4 5 V CTL (V) 55 50 -60 -10 40 Temperature ( C) 90 140 Frequency vs Vcc 1.00 FREQUENCY (MHz) 0.99 0.98 0.97 0.96 0.95 0.94 0.93 0.92 0.91 1.5 2.5 3.5 4.5 Vcc (V) 5.5 6.5 SWITCHING FREQUENCY (MHz) 1.01 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 -50 Switching Frequency vs Temperature 0 50 Temperature ( C) 100 Quiescent Current vs Temperature 500 400 Icc (µA) 300 200 100 0 -50 Vin=4.3V Thermal Shut Down 400 350 300 V FB (mV) 250 200 150 100 50 0 Vin=3.6V Vin=2.7V -10 30 TEMP ( C) 70 110 105 115 125 135 145 155 165 175 185 TEMP ( C) 2006. 4. 20 Revision No : 0 6/6