Preliminary Datasheet LP3133 4-Channel Current Source White LED Driver General Description Features The LP3133 is a low-dropout bias supply for white LEDs is a high-performance alternative to the simple ballast resistors used in conventional white LED designs. It supports 4 white LEDs with regulated constant current for uniform intensity. The LP3133 maintains low dropout current regulators. The LP3133 requires a 50mV dropout at a 20mA load on each output to match the LED brightness. The brightness of LEDs can be tuned through a pulse width modulated signal at the PWM pin. The LP3133 is available in a QFN-16 package. 2.7V to 6V Input Voltage 20mA maxim sink current PWM tuned LED brightness through PWM pin(200Hz-10KHz) Soft Start Function Built-in Thermal Protection IQ<1uA in Shutdown QFN-16 Package RoHS Compliant and 100% Lead (Pb)-Free Typical Application Circuit 13 PWM 15 16 1 2 9 10 11 12 Order Information LP3133 - VBATT VIN LP3133 VOUT EN EN NC NC NC NC NC NC 8 1uF LED1 LED2 LED3 LED4 PGND GND 6 5 4 3 7 14 □ □ □ F: Pb-Free Package Type QV: QFN-16 Marking Information Please see website. Applications LCD Panel Cellular and Smart mobile phone PDA/DSC PMP LP3133 – Ver. 1.0 Datasheet Feb.-2008 Page 1 of 5 Preliminary Datasheet LP3133 Functional Pin Description Part No. NC NC NC NC 11 10 9 Pin Configurations 12 P a c k a g e Ty p e VIN 13 GND 14 8 VOUT 7 PGND PGND PIN NAME LED2 4 5 LED3 16 3 EN LED4 LED1 2 6 NC 15 1 EN NC QFN-16 LP3133 DESCRIPTION QFN-16 1,2,9,10,11,12 NC No Internal Connection. 3 LED4 LED4 cathode terminal. 4 LED3 LED3 cathode terminal. 5 LED2 LED2 cathode terminal. 6 LED1 LED1 cathode terminal 7/14 PGND/GND Ground. 8 Vout Output Voltage Source for connection to the LED anodes. 13 VIN Power Supply. 15/16 EN/PWM Chip Enable(active High).and connects to a GPIO of MCU,the GPIO supply a PWM singal dimming method to control the brightness(0-20mA) of white LEDs and the PWM frequency from 200Hz to 10KHz,the duty from 0% to 100%.the typical frequency is 2KHz. Function Block Diagram LP3133 – Ver. 1.0 Datasheet Feb.-2008 Page 2 of 5 Preliminary Datasheet LP3133 Absolute Maximum Ratings Input Voltage to GND (VINA, VINB) ---------------------------------------------------------------------------- 6V EN/ISET to GND Voltage (Ven/set) ----------------------------------------------------------- 0.3V to Vin+0.3V Maximum DC Output Current(Iout) ----------------------------------------------------------------------- 150mA Operating Junction Temperature Range (TJ) ---------------------------------------------------- 40℃ to 150℃ Maximum Soldering Temperature (at leads, 10sec) ------------------------------------------------------ 300℃ Thermal Information Maximum Power Dissipation (PD) QFN-16 ---------------------------------------------------------------- 1.5W Thermal Resistance (JA) ------------------------------------------------------------------------------------ 50℃/W Electrical Characteristics (Over recommended operating conditions unless specified otherwise) VINA =3.6V,EN=High, TA=25℃ ) Parameter Symbol Conditions Min. 3 0.6 VOUT Input Voltage Output Voltage Range IQ Quiescent Current No Load,1X mode ISHDN ILED-ERR Shutdown Current ENB = GND LED Current Accuracy 3mA< ILED<30mA 19 ILED-LED-ERR LED Channel Matching Any two channel mismatch -3 VEN(L) Enable Threshold Low VEN(H) Enable Threshold High VIN LP3133 – Ver. 1.0 Datasheet Feb.-2008 LP3133 Typ. Max. 5.5 Unit V V VINB 350 uA 0.1 1 µA 20 21 mA 3 % 0.5 V 260 2 V Page 3 of 5 Preliminary Datasheet LP3133 Typical Operating Characteristics LP3133 – Ver. 1.0 Datasheet Feb.-2008 Page 4 of 5 Preliminary Datasheet LP3133 Packaging Information LP3133 – Ver. 1.0 Datasheet Feb.-2008 Page 5 of 5