LTC3210-3 LINER [Linear Technology], LTC3210-3 Datasheet
LTC3210-3
Related parts for LTC3210-3
LTC3210-3 Summary of contents
Page 1
... The charge pump optimizes effi ciency based on the volt- age across the LED current sources. The part powers mode and will automatically switch to boost mode whenever any enabled LED current source begins to enter dropout. The LTC3210-2/LTC3210-3 are available in a 3mm × 3mm 16-lead QFN package. MAIN CAM C4 2.2μ ...
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... LTC3210-2/LTC3210-3 ABSOLUTE MAXIMUM RATINGS V , CPO to GND ........................................ –0. BAT ENM, ENC ................................... –0. (Note 2) ........................................................600mA CPO I .................................................................35mA MLED1-4 PIN CONFIGURATION TOP VIEW C1P 1 CPO 2 17 ENM 3 MLED1 PACKAGE 16-LEAD (3mm × 3mm) PLASTIC QFN T = 125°C, θ ...
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... Low Time to Shutdown (ENC, ENM = Low) Current Source Enable Time (ENC, ENM = High) (Note 5) Note 3: The LTC3210-2/LTC3210-3 are guaranteed to meet performance specifi cations from 0°C to 70°C. Specifi cations over the –40°C to 85°C ambient operating temperature range are assured by design, characterization and correlation with statistical process controls. Note 4: 1.5x mode output impedance is defi ...
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... LTC3210-2/LTC3210-3 TYPICAL PERFORMANCE CHARACTERISTICS Dropout Time from Shutdown 5.1V 2X CPO 1.5X 1V/DIV 1X EN 2V/DIV MODE RESET 321023 G01 500μs/DIV 2x CPO Ripple V = 3.6V BAT I = 200mA CPO C = 2.2μF CPO V CPO 20mV/DIV AC COUPLED 321023 G04 500ns/DIV 1.5x Mode CPO Voltage vs Load Current 4 2.2μF 4 3.3V BAT ...
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... V VOLTAGE (V) BAT ) CPO 400 360 320 280 240 200 160 120 80 40 300 400 500 321023 G16 LTC3210-2/LTC3210 25°C unless otherwise stated. A Oscillator Frequency vs V Voltage BAT 850 840 T = 25°C A 830 820 T = 85°C A 810 800 T = –40°C ...
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... LTC3210-2/LTC3210-3 TYPICAL PERFORMANCE CHARACTERISTICS MLED Pin Current vs MLED Pin Voltage 3.6V BAT 0.00 0.02 0.04 0.06 0.08 0.10 MLED PIN VOLTAGE (V) MLED Current vs ENM Strobe Pulses 3.6V BAT RM = 30. NUMBER OF ENM STROBE PULSES 6 400 350 300 ...
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... ENM input and the programming resistor connected between RM and GND. MLED4 tracks the LED currents of MLED1-3. NC (Pin 7, LTC3210-3 Only): This pin is not connected and can be left fl oating or connected to ground. RM, RC (Pins 8,9): LED Current Programming Resistor Pins. The RM and RC pins will servo to 1.22V. Resistors connected between each of these pins and GND are used to set the high and low LED current levels ...
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... LTC3210-2/LTC3210-3 BLOCK DIAGRAM 800kHz OSCILLATOR 15 V BAT – – 500Ω ENM 50ns FILTER 250k + 1.215V – 500Ω ENC 50ns FILTER 250k 8 C1P C1M C2P CHARGE PUMP 1.215V TIMER ENABLE MAIN 5-BIT 5- BIT DOWN LINEAR COUNTER ...
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... CPO. This mode BAT provides maximum effi ciency and minimum noise. The LTC3210-2/LTC3210-3 will remain in 1x mode until an LED current source drops out. Dropout occurs when a current source voltage becomes too low for the programmed current to be supplied. When dropout is detected, the LTC3210-2/LTC3210-3 will switch into 1 ...
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... Table 1. Charge Pump Output Regulation Voltages Charge Pump Mode 1. When the LTC3210-2/LTC3210-3 operate in either 1.5x mode or 2x mode, the charge pump can be modeled as a Thevenin-equivalent circuit to determine the amount of to slowly charge the current available from the effective input voltage and ef- fective open-loop output resistance, R Figure 2 ...
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... OL shown in Figure 3 and Figure 4. Shutdown Current In shutdown mode all the circuitry is turned off and the LTC3210-2/LTC3210-3 draw a very low current from the V supply. Furthermore, CPO is weakly connected to V BAT The LTC3210-2/LTC3210-3 enter shutdown mode when both the ENM and ENC pins are brought low at 150μ ...
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... ESR. Input noise can be further reduced by powering the LTC3210-2/ LTC3210-3 through a very small series inductor as shown in Figure 5. A 10nH inductor will reject the fast current notches, thereby presenting a nearly constant current load to the input power supply. For economy, the 10nH inductor can be fabricated on the PC board with about 1cm (0.4" ...
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... PCB runs. Magnetic fi elds can also be generated if the fl ying capacitors are not close to the LTC3210-2/LTC3210-3 (i.e., the loop area is large). To decouple capacitive energy transfer, a Faraday shield may be used. This is a grounded PCB trace between the sensitive node and the LTC3210-2/LTC3210-3 pins ...
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... At moderate to high output power, the quiescent current of the LTC3210-2/LTC3210-3 is negligible and the expres- sion above is valid. Once dropout is detected at any LED pin, the LTC3210-2/ LTC3210-3 enable the charge pump in 1.5x mode 1.5x boost mode, the effi ciency is similar to that of a linear regulator with an effective input voltage of 1.5 times the actual input voltage ...
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... Plastic QFN (3mm × 3mm) (Reference LTC DWG # 05-08-1691) 0.70 ±0.05 PACKAGE OUTLINE 0.25 ±0.05 0.50 BSC 0.75 ± 0.05 (4 SIDES) 1.45 ± 0.10 (4-SIDES) 0.200 REF 0.00 – 0.05 LTC3210-2/LTC3210-3 BOTTOM VIEW—EXPOSED PAD PIN 1 NOTCH R = 0.20 TYP R = 0.115 OR 0.25 × 45° CHAMFER TYP 15 16 0.40 ± 0. (UD16) QFN 0904 0.25 ± 0.05 ...
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... Boost Converter Linear Technology Corporation 16 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 3-LED MAIN, One LED Camera C2 C3 2.2μF 2.2μF C1M C2P C2M CPO C4 2.2μF LTC3210-3 MLED1 MLED2 MLED3 CLED RC GND 30.1k 24. COMMENTS V : 1.6V to 18V OUT(MAX 2.8V to 4.5V, V ...