LT3466 Linear Technology, LT3466 Datasheet
LT3466
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LT3466 Summary of contents
Page 1
... Additional features include output voltage limiting when LEDs are disconnected and internal soft-start. The LT3466 is available in a low profile, small footprint (3mm 3mm 0.75mm) DFN package. , LTC and LT are registered trademarks of Linear Technology Corporation ...
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... 267k 300mA SW1 I = 300mA SW2 V = 10V SW1 V = 10V SW2 CTRL1 CTRL2 U W ORDER PART TOP VIEW NUMBER 10 FB1 1 LT3466EDD 9 CTRL1 CTRL2 5 6 FB2 DD PART MARKING DD PACKAGE LBBH = 43 C/W, = 2.96 C MIN TYP MAX 2.7 192 200 192 ...
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... OUT2 Note 3: Current flows out of the pin. Transient Response V OUT1 0.5V/DIV V CTRL1 2V/DIV I L1 200mA/DIV V = 3.6V 5 s/DIV 3466 G01 20mA TO 10mA LED1 CIRCUIT OF FIGURE 1 LT3466 MIN TYP MAX 0.85 0. 600 600 FB1,2 CTRL1,2 250 200 ...
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... LT3466 W U TYPICAL PERFOR A CE CHARACTERISTICS Switch Saturation Voltage (V CESAT 450 400 CE1 CE2 350 300 250 200 150 100 100 150 200 250 300 350 400 SWITCH CURRENT (mA) 3466 G04 Open-Circuit Output Clamp Voltage ...
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... C A 350 300 250 200 150 100 200 400 SCHOTTKY FORWARD DROP (mV) = 20.5k = 48.7k 50 100 3466 G12 600 800 1000 3466 G14 LT3466 Quiescent Current (CTRL1 = CTRL2 = 3V (V) IN 3466 G13 ...
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... LT3466 CTIO S V (Pin 1): Output of Converter 1. This pin is connected OUT1 to the cathode of the internal Schottky diode. Connect an output capacitor from this pin to ground. SW1 (Pin 2): Switch Pin for Converter 1. Connect the inductor at this pin. V (Pin 3): Input Supply Pin. Must be locally bypassed IN with X5R or X7R type ceramic capacitor ...
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... W BLOCK DIAGRA LT3466 3466f 7 ...
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... Minimum Output Current The LT3466 can drive an 8-LED string at 2.5mA LED current without pulse skipping. As current is further reduced, the device may begin skipping pulses. This will result in some low frequency ripple, although the LED current remains regulated on an average basis down to zero ...
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... Converter 1 switches at a lower frequency, reduc- ing its input current. Soft-Start The LT3466 has a separate internal soft-start circuitry for each converter. Soft-start helps to limit the inrush current during start-up. Soft-start is achieved by clamping the output of the error amplifier during the soft-start period. ...
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... Another consideration is the maximum duty cycle achiev- able. In certain applications, the converter needs to oper- ate at the maximum duty cycle in order to light up the maximum number of LEDs. The LT3466 has a fixed oscillator off-time and a variable on-time result, the maximum duty cycle increases as the switching frequency is decreased ...
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... Also, ensure that the inductor has a low DCR (copper wire resistance) to minimize I Recommended inductor values range from Several inductors that work well with the LT3466 are listed in Table 1. Consult each manufacturer for more detailed information and for their entire selection of related parts. ...
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... This technique allows the LEDs to be powered off two alkaline cells. Most portable devices have a 3.3V logic supply voltage which can be used to power the LT3466. The LEDs can be driven straight from the battery, resulting in higher efficiency the CTRL1, CTRL2 LED1,2 ...
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... LEDs when being run off a higher voltage. The maximum num- ber of LEDs that can be driven is constrained by the converter output voltages being clamped at 42V. The LT3466 can be used to power 20 White LEDs (10 per converter) at 20mA when running off two Li-Ion cells in series. W ...
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... OUT2 L1, L2: MURATA LQH32CN150 Li-Ion to 5/5 White LEDs SW1 V SW2 OUT1 OUT2 C OUT1 0.47 F LT3466 FB1 FB2 R R CTRL1 CTRL2 FB1 T 10 38. TAIYO YUDEN JMK107BJ105 TAIYO YUDEN GMK212BJ474 OUT1 OUT2 L1, L2: MURATA LQH32CN150 14 85 ...
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... L1, L2: TOKO A914BYW-330M 85 V 6/6 LEDs OUT2 FB2 10 3466 TA03a 85 V 7/7 LEDs OUT2 FB2 10 3466 TA04a LT3466 Conversion Efficiency = 3. LED CURRENT (mA) 3466 TA03b Conversion Efficiency = 3. LED CURRENT (mA) 3466 TA04b 15 3466f ...
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... OUT2 L1, L2: TOKO A918CE-470M Li-Ion to 9/9 White LEDs SW1 V SW2 OUT1 OUT2 C OUT1 1 F LT3466 FB1 FB2 R CTRL1 CTRL2 T 147k TAIYO YUDEN JMK107BJ105 FB1 IN 16 TAIYO YUDEN UMK325BJ105 OUT1 OUT2 L1, L2: TOKO A920CY-680M 16 85 ...
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... IN2 TAIYO YUDEN GMK316BJ105 OUT1 OUT2 L1, L2: MURATA LQH32CN150 C OUT2 FB2 16.5 3466 TA07a C IN1 0 OUT2 FB2 10 3466 TA08a LT3466 Conversion Efficiency 3.6V IN 10/10 LEDs LED CURRENT (mA) 3466 TA07b Conversion Efficiency 2.4V IN 2/2 LEDs 70 ...
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... U TYPICAL APPLICATIO S 2 Li-Ion Cells to 10/10 White LEDs SW1 V SW2 OUT1 OUT2 C OUT1 0.47 F LT3466 FB1 FB2 R CTRL1 CTRL2 T 63. TAIYO YUDEN LMK212BJ105 FB1 TAIYO YUDEN UMK316BJ474 OUT1 OUT2 L1, L2: TOKO A914BYW-470M 18 90 ...
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... ALL DIMENSIONS ARE IN MILLIMETERS 3. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 4. EXPOSED PAD SHALL BE SOLDER PLATED 5. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE LT3466 R = 0.115 0.38 0.10 TYP 6 10 ...
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... 0 C10 SW1 V SW2 0 OUT1 OUT2 C11 0.22 F LT3466 FB2 R CTRL2 T 20.5k 1% COMMENTS White LEDs 1.8mA White LEDs 1.2mA White LEDs 1.9mA White LEDs Package ...