LT3595 16 Channel Buck Mode LED Driver FEATURESDESCRIPTION ■ 4.5V to 45V Input Supply Range The LT®3595 is a high performance LED Driver designed ■ Up to 50mA LED Current per Channel to drive sixteen independent channels of up to 10 LEDs ■ 100mA, 45V Internal Switches at currents up to 50mA. Series connection of the LEDs ■ 8% Relative LED Current Match at 20mA provides identical LED currents resulting in uniform bright- ■ 16 Independent LED Channels ness. Power switches, Schottky diodes, and compensation ■ 5000:1 True Color PWMTM Dimming Range components are all internal, providing a small converter ■ LEDs Disconnected in Shutdown footprint and lower component cost. The high 2MHz ■ Internal Schottky Diodes switching frequency permits the use of tiny, low profi le ■ Low Quiescent Current inductors and capacitors. A fi xed frequency, current mode ■ 2MHz Switching Frequency architecture results in stable operation over a wide range ■ RSET Pin Sets Master LED Current of supply and output voltage. ■ Typical Effi ciency: 92% A single external resistor sets the LED current for all sixteen ■ Open LED Detection and Thermal Protection channels, and dimming is then controlled for each channel ■ 56-Pin 5mm × 9mm × 0.75mm QFN Package by pulse width modulating the individual PWM pins. Rela- tive current matching among the sixteen drivers is 8% and APPLICATIONS the PWM dimming range is 5000:1. The part is available in a 5mm × 9mm × 0.75mm 56-pin QFN package. ■ LED Video Billboards , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. ■ LCD Televisions True Color PWM is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. ■ Stadium and Advertising Displays TYPICAL APPLICATION16-Channel LED Driver (Three LEDs per Channel), 20mA Current5000:1 PWM VIN Dimming at 100Hz 15V TO 45V 0.47μF 0.47μF 0.47μF 0.47μF 0.47μF 0.47μF 0.47μF 0.47μF 10μF VPWM 5V/DIV μH μH μH μH μH μH μH μH VCC 100 100 100 100 100 100 100 100 ISW 100k L1 SW1 L2 SW2 SW3 L3 SW4 L4 L5 SW5 L6 SW6 SW7 L7 SW8 L8 20mA/DIV OPENLED PWM1 PWM9 PWM2 PWM10 I PWM3 PWM11 LED LED LED 10mA/DIV PWM4 PWM12 BRIGHTNESS BRIGHT- PWM5 LT3595 PWM13 CONTROL NESS 3595 TA01b PWM6 PWM14 400ns/DIV CONTROL PWM7 PWM15 V T = 10ms PWM8 PWM16 IN = 15V 3 LEDS AT 20mA TON = 2μs VCC SHDN GND 3V TO VCC RSET 5.5V L16 SW16 L15 SW15 VIN SW14 L14 SW13 L13 L12 SW12 L11 SW11 VIN SW10 L10 SW9 L9 10μF 75.0k μH μH μH μH μH μH μH μH 100 100 100 100 100 100 100 100 0.47μF 0.47μF 0.47μF 0.47μF 0.47μF 0.47μF 0.47μF 0.47μF 3595 TA01 3595f 1