lt3595a Linear Technology Corporation, lt3595a Datasheet
lt3595a
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lt3595a Summary of contents
Page 1
... SW5 L6 SW6 SW7 L7 SW8 LT3595A SW13 L13 L12 SW12 L11 SW11 V SW10 L10 SW9 IN 0.47μF 0.47μF 0.47μF 0.47μF 0.47μF LT3595A 16 Channel 5000:1 PWM Dimming at 100Hz 0.47μF V PWM 5V/DIV I SW 20mA/DIV L8 PWM9 PWM10 I PWM11 LED LED 10mA/DIV PWM12 BRIGHT- PWM13 NESS PWM14 ...
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... ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LT3595AEUHH#PBF LT3595AEUHH#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based fi nish parts. For more information on lead free part marking, go to: For more information on tape and reel specifi ...
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... OPENLED CC OPENLED = 3.3V Note 2: The LT3595A is guaranteed to meet performance specifi cations from 0°C to 125°C junction temperature. Specifi cations over the –40°C to 125°C operating junction temperature range are assured by design, characterization and correlation with statistical process controls. ...
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... LT3595A TYPICAL PERFORMANCE CHARACTERISTICS Switching Waveforms 10 LEDS V SW1 50V/DIV 10 LEDS I L1 50mA/DIV 5 LEDS V SW2 50V/DIV 5 LEDS I L2 50mA/DIV 3595A G01 400ns/DIV V = 45V 20mA LED LED Current vs PWM Duty Cycle Wide Dimming Range (5000:1) 100 V = 45V IN 10 LEDS AT 20mA PWM FREQUENCY = 100Hz ...
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... G12 OPENLED Waveforms I LED CH 1 20mA/DIV OPENLED 5V/DIV 50V/DIV I LED CH 2 20mA/DIV 3595A G14 LEDS AT 20mA LT3595A T = 25°C, unless otherwise noted. A Schottky Leakage Current vs Temperature 1.4 1.2 1.0 0 0.2 0 100 125 – –25 0 TEMPERATURE (°C) 3595A G10 T = 125° ...
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... LT3595A PIN FUNCTIONS L1-16 (Pins 10, 12, 16, 18, 29, 31, 35, 37, 38, 40, 44, 46): LED Pins. Connection point for the anode of the highest LED in each string. SW1-16 (Pins 11, 13, 15, 17, 30, 32, 34, 36, 39, 41, 43, 45): Switch Pins. Minimize trace area at these pins to minimize EMI. Connect the inductors to these pins ...
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... BLOCK DIAGRAM V CC VREG REG 3.3V 10μF SHDN 24 REF R SET 51 R SET V PWM1-16 IN DFC CONTROL 1 CHANNEL 16X V/I – PWM + S + ISNS – RAMP GENERATOR 2MHz CONTROL OSCILLATOR LT3595A 10μF L1-16 C OUT1-16 0.47μF SW1-16 L 1-16 100μH GND OPENLED 23 3595A BD 3595af 7 IN ...
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... The LT3595A enters shutdown mode when the SHDN pin is lower than 400mV. If the SHDN pin is above 1.6V, then the LT3595A turns on. At the start of each oscillator cycle, the power switch is turned on. Current ramps up through the output capacitor, the inductor, and the switch to ground. When the voltage across the output capacitor is larger than the LEDs’ ...
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... OPERATION Discontinuous Current Mode The LT3595A can drive a 10-LED string at 15mA LED current operating in continuous conduction mode using the recommended external components shown in the ap- plication circuit on page 1 of this data sheet. As current is further reduced, the regulator enters discontinuous conduction mode. The photo in Figure 1 details circuit operation driving ten LEDs at 10mA load ...
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... Consult the manufacturers for detailed information on their entire selection of ceramic parts. 10 Open LED Detection The LT3595A detects an open LED on any channel and reports it to the OPENLED pin. The fault also reports dur- ing startup until the output voltage and LED current are = 3.5V) LED in regulation. Therefore, it can also be used as a “ ...
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... LED current is 2μA. When multiple channels are modulated, the rising edges of PWM1-16 must be synchronized. The falling edges may be asynchronous. A sample timing diagram is shown in Figure 3. SYNCHRONIZED RISING EDGES = 2μ 10ms MAX LT3595A produces 10mA, the minimum SET 3595A F03 3595af 11 ...
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... LT3595A APPLICATIONS INFORMATION Board Layout Considerations As with all switching regulators, careful attention must be paid to the PCB board layout and component placement. To prevent electromagnetic interference (EMI) problems, proper layout of high frequency switching paths is essential. Minimize the length and area of all traces connected to 12 the SW1-16 and PWM1-16 pins ...
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... APPLICATIONS INFORMATION Figure 6. PCB Layer 3 Figure 7. PCB Layer 4 LT3595A 3595af 13 ...
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... I (mA)* LED *I ADJUSTED WITH R LED SET 14 0.47μF 0.47μF 0.47μF SW3 L3 SW4 L4 L5 SW5 L6 LT3595A SW14 L14 SW13 L13 L12 SW12 L11 IN 0.47μF 0.47μF 0.47μF 50 3595A TA02b 0.47μF 0.47μF 0.47μF SW6 SW7 L7 SW8 L8 PWM9 PWM10 PWM11 LED PWM12 ...
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... DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.20mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE LT3595A 0.70 0.05 PACKAGE OUTLINE PIN 1 NOTCH R = 0.30 TYP OR ...
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... McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 0.47μF 0.47μF 0.47μF 0.47μF SW4 L4 L5 SW5 L6 SW6 SW7 L7 SW8 PWM10 PWM11 PWM12 LT3595A PWM13 PWM14 PWM15 PWM16 SW13 L13 L12 SW12 L11 SW11 V SW10 L10 SW9 IN 0.47μF 0.47μF 0.47μF 0.47μF ...